/* Estilos para os novos modais */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(8px);
    z-index: var(--z-modal);
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.modal.show {
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 1;
}

.modal-content {
    background: var(--surface);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-xl);
    width: 90%;
    max-width: 600px;
    max-height: 90vh;
    overflow-y: auto;
    transform: scale(0.9);
    transition: transform var(--transition-normal);
}

.modal.show .modal-content {
    transform: scale(1);
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-xl);
    border-bottom: 1px solid var(--border-color);
}

.modal-header h2 {
    color: var(--text-primary);
    font-size: var(--font-size-xl);
    font-weight: 600;
    margin: 0;
}

.modal-close {
    background: none;
    border: none;
    font-size: var(--font-size-2xl);
    color: var(--text-secondary);
    cursor: pointer;
    padding: var(--space-sm);
    border-radius: var(--border-radius-sm);
    transition: color var(--transition-fast);
}

.modal-close:hover {
    color: var(--text-primary);
    background: var(--background-secondary);
}

.modal-body {
    padding: var(--space-xl);
}

/* Formulários dos modais */
.questions-form,
.review-form,
.notes-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.form-group label {
    font-weight: 500;
    color: var(--text-primary);
    font-size: var(--font-size-sm);
}

.form-group input,
.form-group select,
.form-group textarea {
    padding: var(--space-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    font-size: var(--font-size-base);
    color: var(--text-primary);
    background: var(--background-primary);
    transition: border-color var(--transition-fast);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

/* Toolbar para anotações */
.notes-toolbar {
    display: flex;
    gap: var(--space-sm);
    margin-top: var(--space-sm);
}

.notes-toolbar button {
    background: var(--background-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    padding: var(--space-sm) var(--space-md);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.notes-toolbar button:hover {
    background: var(--primary-color);
    color: var(--text-inverse);
    border-color: var(--primary-color);
}

/* Opções especiais */
.review-intervals,
.notes-options {
    background: var(--background-secondary);
    padding: var(--space-lg);
    border-radius: var(--border-radius-sm);
    border: 1px solid var(--border-color);
}

.review-intervals h4,
.notes-options label {
    margin-bottom: var(--space-md);
    color: var(--text-primary);
    font-weight: 500;
}

.interval-options,
.notes-options {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.interval-options label,
.notes-options label {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    font-weight: normal;
    color: var(--text-secondary);
}

.interval-options input[type="checkbox"],
.notes-options input[type="checkbox"] {
    width: auto;
    margin: 0;
}

.interval-options small {
    color: var(--text-tertiary);
    font-size: var(--font-size-xs);
    margin-top: var(--space-xs);
}

/* Ações do modal */
.modal-actions {
    display: flex;
    gap: var(--space-md);
    justify-content: flex-end;
    margin-top: var(--space-xl);
    padding-top: var(--space-lg);
    border-top: 1px solid var(--border-color);
}

.modal-actions .btn {
    padding: var(--space-md) var(--space-xl);
    border-radius: var(--border-radius-sm);
    font-weight: 500;
    font-size: var(--font-size-sm);
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.modal-actions .btn-primary {
    background: var(--primary-color);
    color: var(--text-inverse);
}

.modal-actions .btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.modal-actions .btn-secondary {
    background: var(--background-secondary);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.modal-actions .btn-secondary:hover {
    background: var(--background-tertiary);
    color: var(--text-primary);
}

/* Prévia de anotações */
.notes-preview {
    margin-top: var(--space-xl);
    padding: var(--space-lg);
    background: var(--background-secondary);
    border-radius: var(--border-radius-sm);
    border: 1px solid var(--border-color);
}

.notes-preview h4 {
    color: var(--text-primary);
    margin-bottom: var(--space-md);
    font-size: var(--font-size-lg);
}

#preview-content {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Responsividade para modais */
@media (max-width: 768px) {
    .modal-content {
        width: 95%;
        max-height: 95vh;
    }
    
    .modal-header,
    .modal-body {
        padding: var(--space-lg);
    }
    
    .modal-actions {
        flex-direction: column;
    }
    
    .modal-actions .btn {
        width: 100%;
        justify-content: center;
    }
    
    .notes-toolbar {
        flex-wrap: wrap;
    }
    
    .review-intervals,
    .notes-options {
        padding: var(--space-md);
    }
}

/* Animações para elementos dos modais */
.form-group {
    animation: slideInUp 0.3s ease-out;
}

@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Estados de validação */
.form-group input:invalid,
.form-group select:invalid,
.form-group textarea:invalid {
    border-color: var(--error-color);
}

.form-group input:valid,
.form-group select:valid,
.form-group textarea:valid {
    border-color: var(--success-color);
}

/* Melhorias nos gráficos */
.chart-card {
    background: var(--surface);
    border-radius: var(--border-radius-lg);
    padding: var(--space-xl);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
}

.chart-card h3 {
    color: var(--text-primary);
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin-bottom: var(--space-lg);
    text-align: center;
}

.chart-card canvas {
    max-height: 300px;
}

/* Melhorias nas estatísticas */
.stat-card {
    background: var(--surface);
    border-radius: var(--border-radius-lg);
    padding: var(--space-xl);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: var(--space-lg);
    transition: transform var(--transition-fast);
}

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.stat-icon {
    width: 60px;
    height: 60px;
    border-radius: var(--border-radius);
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-inverse);
    font-size: var(--font-size-xl);
}

.stat-info h3 {
    color: var(--text-primary);
    font-size: var(--font-size-2xl);
    font-weight: 700;
    margin-bottom: var(--space-xs);
}

.stat-info p {
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
    font-weight: 500;
}
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* ===== SISTEMA DE CORES ADAPTATIVO ===== */
    
    /* Cores principais */
    --primary-color: #6366f1;
    --primary-light: #818cf8;
    --primary-dark: #4f46e5;
    --secondary-color: #f59e0b;
    --secondary-light: #fbbf24;
    --secondary-dark: #d97706;
    
    /* Cores de estado */
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    --info-color: #3b82f6;
    
    /* ===== SISTEMA DE CORES TEMÁTICAS ===== */
    
    /* Light Mode (padrão) */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --bg-quaternary: #e2e8f0;
    
    --surface-primary: rgba(255, 255, 255, 0.95);
    --surface-secondary: rgba(248, 250, 252, 0.9);
    --surface-elevated: rgba(255, 255, 255, 0.98);
    
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-tertiary: #94a3b8;
    --text-inverse: #ffffff;
    --text-muted: #cbd5e1;
    
    --border-primary: rgba(226, 232, 240, 0.5);
    --border-secondary: rgba(226, 232, 240, 0.3);
    --border-light: rgba(241, 245, 249, 0.8);
    
    --shadow-light: 0 1px 3px rgba(0, 0, 0, 0.05);
    --shadow-medium: 0 4px 12px rgba(0, 0, 0, 0.08);
    --shadow-heavy: 0 8px 25px rgba(0, 0, 0, 0.12);
    --shadow-intense: 0 12px 40px rgba(0, 0, 0, 0.15);
    
    --backdrop-blur: blur(10px);
    --backdrop-blur-heavy: blur(15px);
    
    /* Gradientes */
    --gradient-main: linear-gradient(135deg, 
        rgba(248, 250, 252, 0.8) 0%, 
        rgba(241, 245, 249, 0.9) 50%, 
        rgba(226, 232, 240, 0.8) 100%);
        
    --gradient-hero: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.95) 0%, 
        rgba(248, 250, 252, 0.90) 50%,
        rgba(241, 245, 249, 0.85) 100%);
        
    --gradient-card: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.95) 0%, 
        rgba(252, 252, 254, 0.90) 100%);
    
    /* Cores neutras existentes (mantidas para compatibilidade) */
    --background-primary: var(--bg-primary);
    --background-secondary: var(--bg-secondary);
    --background-tertiary: var(--bg-tertiary);
    --surface: var(--surface-primary);
    --surface-elevated: var(--surface-elevated);
    
    /* Bordas */
    --border-color: #e2e8f0;
    --border-color-light: #f1f5f9;
    --border-radius: 12px;
    --border-radius-sm: 8px;
    --border-radius-lg: 16px;
    
    /* Sombras (mantidas para compatibilidade) */
    --shadow-sm: var(--shadow-light);
    --shadow-md: var(--shadow-medium);
    --shadow-lg: var(--shadow-heavy);
    --shadow-xl: var(--shadow-intense);
    
    /* Espaçamento */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;
    
    /* Tipografia */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    --font-size-5xl: 3rem;
    
    /* Transições */
    --transition-fast: 150ms ease-in-out;
    --transition-normal: 250ms ease-in-out;
    --transition-slow: 350ms ease-in-out;
    
    /* Z-indexes */
    --z-header: 1000;
    --z-modal: 2000;
    --z-notification: 3000;
}

/* ===== DARK MODE VARIABLES ===== */
.dark-mode {
    /* Backgrounds escuros */
    --bg-primary: #0f1419;
    --bg-secondary: #1a1f26;
    --bg-tertiary: #2a303a;
    --bg-quaternary: #3a4148;
    
    --surface-primary: rgba(26, 31, 38, 0.95);
    --surface-secondary: rgba(42, 48, 58, 0.9);
    --surface-elevated: rgba(58, 65, 72, 0.98);
    
    /* Texto escuro */
    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-tertiary: #94a3b8;
    --text-inverse: #0f1419;
    --text-muted: #64748b;
    
    /* Bordas escuras */
    --border-primary: rgba(71, 85, 105, 0.3);
    --border-secondary: rgba(71, 85, 105, 0.2);
    --border-light: rgba(94, 163, 184, 0.1);
    
    /* Sombras escuras */
    --shadow-light: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-medium: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-heavy: 0 8px 25px rgba(0, 0, 0, 0.5);
    --shadow-intense: 0 12px 40px rgba(0, 0, 0, 0.6);
    
    --backdrop-blur: blur(12px);
    --backdrop-blur-heavy: blur(20px);
    
    /* Gradientes escuros */
    --gradient-main: linear-gradient(135deg, 
        rgba(15, 20, 25, 0.8) 0%, 
        rgba(26, 31, 38, 0.9) 50%, 
        rgba(42, 48, 58, 0.8) 100%);
        
    --gradient-hero: linear-gradient(135deg, 
        rgba(15, 20, 25, 0.95) 0%, 
        rgba(26, 31, 38, 0.90) 50%,
        rgba(42, 48, 58, 0.85) 100%);
        
    --gradient-card: linear-gradient(135deg, 
        rgba(26, 31, 38, 0.95) 0%, 
        rgba(42, 48, 58, 0.90) 100%);
    
    /* Atualizar variáveis de compatibilidade */
    --background-primary: var(--bg-primary);
    --background-secondary: var(--bg-secondary);
    --background-tertiary: var(--bg-tertiary);
    --surface: var(--surface-primary);
    --surface-elevated: var(--surface-elevated);
    --border-color: rgba(71, 85, 105, 0.3);
    --border-color-light: rgba(71, 85, 105, 0.2);
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    :root {
        --background-primary: #0f172a;
        --background-secondary: #1e293b;
        --background-tertiary: #334155;
        --surface: #1e293b;
        --surface-elevated: #334155;
        
        --text-primary: #f8fafc;
        --text-secondary: #cbd5e1;
        --text-tertiary: #94a3b8;
        
        --border-color: #334155;
        --border-color-light: #475569;
    }
}

/* ===== LAYOUT ESTRUTURAL COM VARIÁVEIS ADAPTATIVAS ===== */

/* Layout principal com variáveis temáticas */
body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--gradient-main);
    overflow-x: hidden;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: all var(--transition-normal);
}

/* Header adaptativo */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--surface-elevated);
    backdrop-filter: var(--backdrop-blur-heavy);
    border-bottom: 1px solid var(--border-light);
    z-index: var(--z-header);
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-medium);
}

/* Main content adaptativo */
.main {
    margin-top: 80px;
    flex: 1;
    background: var(--gradient-main);
    position: relative;
}

.main::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        radial-gradient(circle at 20% 20%, rgba(99, 102, 241, 0.05) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(245, 158, 11, 0.05) 0%, transparent 50%),
        radial-gradient(circle at 40% 60%, rgba(16, 185, 129, 0.03) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
}

/* Seções com variáveis adaptativas */
section {
    position: relative;
    z-index: 1;
}

.hero {
    padding: var(--space-3xl) 0;
    background: var(--gradient-hero);
    position: relative;
    overflow: hidden;
    border-bottom: 1px solid var(--border-secondary);
}

.about {
    padding: var(--space-3xl) 0;
    background: var(--gradient-card);
    border-top: 1px solid var(--border-secondary);
    border-bottom: 1px solid var(--border-secondary);
}

.timer-section {
    padding: var(--space-3xl) 0;
    background: var(--gradient-hero);
    position: relative;
    box-shadow: 
        inset 0 1px 0 var(--border-light),
        var(--shadow-medium);
}

.timer-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(ellipse at top, rgba(99, 102, 241, 0.1) 0%, transparent 50%),
        radial-gradient(ellipse at bottom, rgba(245, 158, 11, 0.05) 0%, transparent 50%);
    pointer-events: none;
}

.stats-section {
    padding: var(--space-3xl) 0;
    background: var(--gradient-card);
    border-top: 1px solid var(--border-secondary);
}

.articles-section {
    padding: var(--space-3xl) 0;
    background: var(--gradient-hero);
}

/* Footer adaptativo */
.footer {
    background: linear-gradient(135deg, #1e293b 0%, #334155 100%);
    color: var(--text-inverse);
    padding: var(--space-3xl) 0 var(--space-xl);
    position: relative;
    box-shadow: var(--shadow-heavy);
}

/* ===== SISTEMA DE CARDS COM VARIÁVEIS ADAPTATIVAS ===== */

/* Card base com variáveis temáticas */
.card {
    background: var(--surface-primary);
    border-radius: var(--border-radius-lg);
    padding: var(--space-xl);
    box-shadow: 
        var(--shadow-light),
        var(--shadow-medium),
        0 0 0 1px var(--border-light);
    border: 1px solid var(--border-primary);
    transition: all var(--transition-normal);
    position: relative;
    backdrop-filter: var(--backdrop-blur);
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: var(--border-radius-lg) var(--border-radius-lg) 0 0;
    opacity: 0.8;
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: 
        var(--shadow-medium),
        var(--shadow-heavy),
        0 0 0 1px var(--border-light);
}

/* Card de estatísticas com variáveis */
.stat-card {
    background: var(--surface-primary);
    border-radius: var(--border-radius-lg);
    padding: var(--space-xl);
    box-shadow: 
        var(--shadow-medium),
        var(--shadow-heavy),
        0 0 0 1px var(--border-primary);
    border: 1px solid var(--border-primary);
    display: flex;
    align-items: center;
    gap: var(--space-lg);
    transition: all var(--transition-normal);
    position: relative;
    backdrop-filter: var(--backdrop-blur);
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(180deg, var(--primary-color), var(--primary-light));
    border-radius: var(--border-radius-lg) 0 0 var(--border-radius-lg);
}

.stat-card:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 
        var(--shadow-heavy),
        var(--shadow-intense),
        0 0 0 1px var(--border-light);
}

/* Card de gráficos */
.chart-card {
    background: var(--surface-elevated);
    border-radius: var(--border-radius-lg);
    padding: var(--space-xl);
    box-shadow: 
        var(--shadow-medium),
        var(--shadow-heavy),
        inset 0 1px 0 var(--border-light);
    border: 1px solid var(--border-secondary);
    backdrop-filter: var(--backdrop-blur);
    transition: all var(--transition-normal);
}

.chart-card:hover {
    transform: translateY(-2px);
    box-shadow: 
        var(--shadow-heavy),
        var(--shadow-intense),
        inset 0 1px 0 var(--border-light);
}

.chart-card h3 {
    color: var(--text-primary);
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin-bottom: var(--space-lg);
    text-align: center;
    position: relative;
    padding-bottom: var(--space-sm);
}

.chart-card h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 40px;
    height: 2px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 1px;
}

/* About cards com variáveis */
.about-card {
    background: var(--surface-primary);
    padding: var(--space-xl);
    border-radius: var(--border-radius-lg);
    box-shadow: 
        var(--shadow-medium),
        var(--shadow-heavy),
        0 0 0 1px var(--border-light);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
    backdrop-filter: var(--backdrop-blur);
    border: 1px solid var(--border-primary);
}

.about-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
}

.about-card:hover {
    transform: translateY(-6px) scale(1.02);
    box-shadow: 
        var(--shadow-heavy),
        var(--shadow-intense),
        0 0 0 1px var(--border-light);
}

/* Article cards com variáveis */
.article-card {
    background: var(--surface-primary);
    border-radius: var(--border-radius-lg);
    box-shadow: 
        var(--shadow-medium),
        var(--shadow-heavy),
        0 0 0 1px var(--border-primary);
    overflow: hidden;
    transition: all var(--transition-normal);
    border: 1px solid var(--border-primary);
    backdrop-filter: var(--backdrop-blur);
}

.article-card:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 
        var(--shadow-intense),
        0 20px 60px rgba(0, 0, 0, 0.08),
        0 0 0 1px var(--border-light);
}

/* Timer display com variáveis */
.timer-display {
    grid-area: timer-display;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-xl);
    background: var(--surface-elevated);
    padding: var(--space-2xl);
    border-radius: var(--border-radius-lg);
    box-shadow: 
        var(--shadow-heavy),
        var(--shadow-intense),
        inset 0 1px 0 var(--border-light);
    border: 1px solid var(--border-secondary);
    backdrop-filter: var(--backdrop-blur-heavy);
}

/* Study session card */
.study-session {
    grid-area: study-session;
    background: var(--surface-primary);
    padding: var(--space-xl);
    border-radius: var(--border-radius-lg);
    box-shadow: 
        var(--shadow-medium),
        var(--shadow-heavy),
        0 0 0 1px var(--border-light);
    border: 1px solid var(--border-primary);
    backdrop-filter: var(--backdrop-blur);
    transition: all var(--transition-normal);
}

.study-session:hover {
    box-shadow: 
        var(--shadow-heavy),
        var(--shadow-intense),
        0 0 0 1px var(--border-light);
}

/* Timer settings card */
.timer-settings {
    grid-area: quick-stats;
    background: var(--surface-primary);
    padding: var(--space-xl);
    border-radius: var(--border-radius-lg);
    box-shadow: 
        var(--shadow-medium),
        var(--shadow-heavy),
        0 0 0 1px var(--border-light);
    max-height: 600px;
    overflow-y: auto;
    border: 1px solid var(--border-primary);
    backdrop-filter: var(--backdrop-blur);
}

/* Review schedule card */
.review-schedule {
    grid-area: schedule;
    background: var(--surface-primary);
    padding: var(--space-xl);
    border-radius: var(--border-radius-lg);
    box-shadow: 
        var(--shadow-medium),
        var(--shadow-heavy),
        0 0 0 1px var(--border-light);
    border: 1px solid var(--border-primary);
    backdrop-filter: var(--backdrop-blur);
}

/* ===== ÍCONES DE ESTATÍSTICAS MELHORADOS ===== */
.stat-icon {
    width: 65px;
    height: 65px;
    border-radius: var(--border-radius);
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-inverse);
    font-size: var(--font-size-xl);
    box-shadow: 
        0 4px 12px rgba(99, 102, 241, 0.3),
        0 2px 6px rgba(99, 102, 241, 0.2);
    position: relative;
    overflow: hidden;
}

.stat-icon::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: linear-gradient(45deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transform: rotate(45deg);
    transition: all 0.6s ease;
    opacity: 0;
}

.stat-card:hover .stat-icon::before {
    opacity: 1;
    animation: shimmer 1.5s ease-in-out;
}

@keyframes shimmer {
    0% { transform: translateX(-100%) translateY(-100%) rotate(45deg); }
    100% { transform: translateX(100%) translateY(100%) rotate(45deg); }
}

/* ===== RESPONSIVIDADE MELHORADA ===== */
@media (max-width: 1024px) {
    .timer-container {
        grid-template-columns: 1fr;
        gap: var(--space-xl);
    }
    
    .main {
        background: linear-gradient(135deg, 
            rgba(248, 250, 252, 0.9) 0%, 
            rgba(241, 245, 249, 0.95) 100%);
    }
}

@media (max-width: 768px) {
    .card,
    .stat-card,
    .chart-card,
    .about-card,
    .article-card {
        backdrop-filter: blur(5px);
    }
    
    .timer-display {
        padding: var(--space-lg);
        backdrop-filter: blur(8px);
    }
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: var(--space-md);
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl); }
h5 { font-size: var(--font-size-lg); }
h6 { font-size: var(--font-size-base); }

p {
    margin-bottom: var(--space-md);
    color: var(--text-secondary);
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--primary-dark);
}

/* Utility Classes */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

.section-header {
    text-align: center;
    margin-bottom: var(--space-3xl);
}

.section-header h2 {
    margin-bottom: var(--space-md);
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-header p {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-md) var(--space-xl);
    border: none;
    border-radius: var(--border-radius);
    font-size: var(--font-size-base);
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    text-decoration: none;
    user-select: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    color: var(--text-inverse);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
}

.btn-secondary {
    background: var(--surface);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
    background: var(--background-secondary);
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.btn-preset {
    padding: var(--space-sm) var(--space-md);
    font-size: var(--font-size-sm);
    background: var(--background-tertiary);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.btn-preset:hover {
    background: var(--primary-color);
    color: var(--text-inverse);
    border-color: var(--primary-color);
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(15px);
    border-bottom: 1px solid var(--border-color-light);
    z-index: var(--z-header);
    transition: all var(--transition-normal);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.05);
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-md) var(--space-lg);
    max-width: 1200px;
    margin: 0 auto;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--primary-color);
}

.nav-brand i {
    font-size: var(--font-size-2xl);
}

.nav-links {
    display: flex;
    gap: var(--space-xl);
}

.nav-link {
    padding: var(--space-sm) var(--space-md);
    border-radius: var(--border-radius-sm);
    transition: all var(--transition-fast);
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    background: var(--background-secondary);
    color: var(--primary-color);
}

.nav-toggle {
    display: none;
    font-size: var(--font-size-xl);
    cursor: pointer;
    color: var(--text-primary);
}

/* Main Content */
.main {
    margin-top: 80px;
    flex: 1;
    background: linear-gradient(135deg, 
        rgba(248, 250, 252, 0.8) 0%, 
        rgba(241, 245, 249, 0.9) 50%, 
        rgba(226, 232, 240, 0.8) 100%);
    position: relative;
}

/* Hero Section - já definida no início do arquivo */

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        radial-gradient(circle at 20% 20%, rgba(99, 102, 241, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(245, 158, 11, 0.1) 0%, transparent 50%);
    pointer-events: none;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-3xl);
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
    position: relative;
    z-index: 1;
}

.hero-title {
    font-size: var(--font-size-5xl);
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: var(--space-lg);
    background: linear-gradient(135deg, var(--text-primary), var(--primary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: var(--font-size-xl);
    color: var(--text-secondary);
    margin-bottom: var(--space-xl);
    line-height: 1.5;
}

.hero-benefits {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
    margin-bottom: var(--space-xl);
}

.benefit-item {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    color: var(--text-secondary);
}

.benefit-item i {
    color: var(--success-color);
    font-size: var(--font-size-lg);
}

.hero-cta {
    display: flex;
    gap: var(--space-lg);
    flex-wrap: wrap;
}

/* Pomodoro Clock Visual */
.pomodoro-clock {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-xl);
}

.clock-face {
    position: relative;
    width: 300px;
    height: 300px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    padding: 20px;
    box-shadow: var(--shadow-xl);
}

.clock-face::before {
    content: '';
    position: absolute;
    top: 10px;
    left: 10px;
    right: 10px;
    bottom: 10px;
    border-radius: 50%;
    background: var(--surface);
    box-shadow: inset var(--shadow-lg);
}

.clock-hand {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 4px;
    height: 80px;
    background: var(--primary-color);
    border-radius: 2px;
    transform-origin: bottom center;
    transform: translate(-50%, -100%) rotate(0deg);
    z-index: 2;
    animation: clockRotate 25s linear infinite;
}

.clock-numbers {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 1;
}

.clock-numbers span {
    position: absolute;
    font-weight: 600;
    color: var(--primary-color);
    font-size: var(--font-size-lg);
}

.clock-numbers span:nth-child(1) { top: -100px; left: -8px; }
.clock-numbers span:nth-child(2) { top: -5px; right: -80px; }
.clock-numbers span:nth-child(3) { bottom: -100px; left: -8px; }
.clock-numbers span:nth-child(4) { top: -5px; left: -90px; }

.clock-stats {
    display: flex;
    gap: var(--space-xl);
}

.stat {
    text-align: center;
    padding: var(--space-lg);
    background: var(--surface);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    min-width: 100px;
}

.stat-number {
    display: block;
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
}

@keyframes clockRotate {
    from { transform: translate(-50%, -100%) rotate(0deg); }
    to { transform: translate(-50%, -100%) rotate(360deg); }
}

/* About Section - já definida no início do arquivo */

.about-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--space-xl);
}

/* About cards - já definidos no sistema de cards melhorado */

.about-card.featured {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    color: var(--text-inverse);
}

.about-card.featured::before {
    background: rgba(255, 255, 255, 0.3);
}

.card-icon {
    width: 60px;
    height: 60px;
    border-radius: var(--border-radius);
    background: linear-gradient(135deg, var(--primary-light), var(--secondary-light));
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--space-lg);
}

.card-icon i {
    font-size: var(--font-size-2xl);
    color: var(--text-inverse);
}

.about-card.featured .card-icon {
    background: rgba(255, 255, 255, 0.2);
}

.card-benefits {
    margin-top: var(--space-lg);
}

.card-benefits h4 {
    margin-bottom: var(--space-md);
    color: var(--primary-color);
    font-size: var(--font-size-lg);
}

.about-card.featured .card-benefits h4 {
    color: var(--text-inverse);
}

.card-benefits ul {
    list-style: none;
}

.card-benefits li {
    padding: var(--space-sm) 0;
    position: relative;
    padding-left: var(--space-lg);
}

.card-benefits li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--success-color);
    font-weight: bold;
}

.about-card.featured .card-benefits li::before {
    color: var(--text-inverse);
}

/* Forgetting Curve Chart */
.forgetting-curve {
    margin-top: var(--space-lg);
    height: 200px;
}

.forgetting-curve canvas {
    border-radius: var(--border-radius);
}

/* Spaced Repetition Demo */
.spaced-repetition-demo {
    margin-top: var(--space-lg);
}

.review-timeline {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-md);
}

.review-point {
    padding: var(--space-md);
    border-radius: var(--border-radius);
    text-align: center;
    font-size: var(--font-size-sm);
    font-weight: 500;
}

.review-point.easy { background: var(--success-color); color: white; }
.review-point.good { background: var(--info-color); color: white; }
.review-point.hard { background: var(--warning-color); color: white; }
.review-point.again { background: var(--error-color); color: white; }

.review-point small {
    display: block;
    margin-top: var(--space-xs);
    opacity: 0.8;
}

/* Methodology Flow */
.methodology-flow {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: var(--space-lg);
    flex-wrap: wrap;
    gap: var(--space-md);
}

.flow-step {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-md);
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--border-radius);
    flex: 1;
    min-width: 120px;
    justify-content: center;
}

.flow-arrow {
    font-size: var(--font-size-lg);
    color: rgba(255, 255, 255, 0.7);
    display: flex;
    align-items: center;
}

/* Timer Section - já definida no início do arquivo */

/* ===== GRID LAYOUT RESPONSIVO ===== */

/* Timer section com CSS Grid */
.timer-container {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    grid-template-areas: 
        "timer-display study-session quick-stats";
    gap: var(--space-xl);
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

/* Áreas do grid */
.timer-display {
    grid-area: timer-display;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-xl);
    background: rgba(255, 255, 255, 0.9);
    padding: var(--space-2xl);
    border-radius: var(--border-radius-lg);
    box-shadow: 
        0 4px 20px rgba(0, 0, 0, 0.08),
        0 8px 40px rgba(0, 0, 0, 0.06),
        inset 0 1px 0 rgba(255, 255, 255, 0.8);
    border: 1px solid rgba(226, 232, 240, 0.4);
    backdrop-filter: blur(12px);
}

.study-session {
    grid-area: study-session;
    background: rgba(255, 255, 255, 0.95);
    padding: var(--space-xl);
    border-radius: var(--border-radius-lg);
    box-shadow: 
        0 2px 12px rgba(0, 0, 0, 0.06),
        0 6px 30px rgba(0, 0, 0, 0.08),
        0 0 0 1px rgba(255, 255, 255, 0.6);
    border: 1px solid rgba(226, 232, 240, 0.3);
    backdrop-filter: blur(10px);
    transition: all var(--transition-normal);
}

.timer-settings {
    grid-area: quick-stats;
    background: rgba(255, 255, 255, 0.95);
    padding: var(--space-xl);
    border-radius: var(--border-radius-lg);
    box-shadow: 
        0 2px 12px rgba(0, 0, 0, 0.06),
        0 6px 30px rgba(0, 0, 0, 0.08),
        0 0 0 1px rgba(255, 255, 255, 0.6);
    max-height: 600px;
    overflow-y: auto;
    border: 1px solid rgba(226, 232, 240, 0.3);
    backdrop-filter: blur(10px);
}

/* Stats section com grid melhorado */
.stats-grid {
    display: grid;
    grid-template-columns: 1fr;
    grid-template-areas:
        "overview"
        "charts"
        "schedule";
    gap: var(--space-xl);
}

.stats-overview {
    grid-area: overview;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-lg);
}

.charts-container {
    grid-area: charts;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--space-lg);
}

.review-schedule {
    grid-area: schedule;
    background: rgba(255, 255, 255, 0.95);
    padding: var(--space-xl);
    border-radius: var(--border-radius-lg);
    box-shadow: 
        0 2px 12px rgba(0, 0, 0, 0.06),
        0 6px 30px rgba(0, 0, 0, 0.08),
        0 0 0 1px rgba(255, 255, 255, 0.6);
    border: 1px solid rgba(226, 232, 240, 0.3);
    backdrop-filter: blur(10px);
}

/* Articles com grid responsivo */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: var(--space-xl);
    margin-bottom: var(--space-3xl);
}

.article-card.featured {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 0;
}

/* ===== RESPONSIVIDADE APRIMORADA ===== */

/* Desktop Large (1200px+) */
@media (min-width: 1200px) {
    .timer-container {
        grid-template-columns: 2fr 1.5fr 1fr;
        grid-template-areas: 
            "timer-display study-session quick-stats";
    }
    
    .stats-grid {
        grid-template-areas:
            "overview overview"
            "charts schedule";
        grid-template-columns: 2fr 1fr;
    }
}

/* Tablet (768px - 1199px) */
@media (max-width: 1199px) and (min-width: 768px) {
    .timer-container {
        grid-template-columns: 1fr 1fr;
        grid-template-areas: 
            "timer-display study-session"
            "quick-stats quick-stats";
        gap: var(--space-lg);
    }
    
    .stats-grid {
        grid-template-areas:
            "overview"
            "charts"
            "schedule";
    }
    
    .article-card.featured {
        grid-template-columns: 1fr 1.5fr;
    }
}

/* Mobile (até 767px) */
@media (max-width: 767px) {
    .timer-container {
        grid-template-columns: 1fr;
        grid-template-areas: 
            "timer-display"
            "study-session"
            "quick-stats";
        gap: var(--space-md);
        padding: 0 var(--space-md);
    }
    
    .timer-display {
        padding: var(--space-lg);
    }
    
    .stats-overview {
        grid-template-columns: 1fr;
    }
    
    .charts-container {
        grid-template-columns: 1fr;
    }
    
    .articles-grid {
        grid-template-columns: 1fr;
    }
    
    .article-card.featured {
        grid-template-columns: 1fr;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .about-grid {
        grid-template-columns: 1fr;
    }
}

/* Mobile Small (até 480px) */
@media (max-width: 480px) {
    .container {
        padding: 0 var(--space-sm);
    }
    
    .timer-container {
        gap: var(--space-sm);
        padding: 0 var(--space-sm);
    }
    
    .timer-display {
        padding: var(--space-md);
    }
    
    .timer-circle {
        width: 200px;
        height: 200px;
    }
    
    .timer-time {
        font-size: var(--font-size-2xl);
    }
}

/* Timer Display - já definido no sistema de cards melhorado */

.timer-circle {
    position: relative;
    width: 280px;
    height: 280px;
}

.timer-svg {
    width: 100%;
    height: 100%;
    transform: rotate(-90deg);
}

.timer-background {
    fill: none;
    stroke: var(--border-color);
    stroke-width: 8;
}

.timer-progress {
    fill: none;
    stroke: url(#timerGradient);
    stroke-width: 8;
    stroke-linecap: round;
    stroke-dasharray: 565.48;
    stroke-dashoffset: 0;
    transition: stroke-dashoffset 1s ease-in-out;
}

.timer-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
}

.timer-time {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: var(--space-sm);
}

.timer-phase {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    margin-bottom: var(--space-xs);
}

.timer-cycle {
    font-size: var(--font-size-sm);
    color: var(--text-tertiary);
}

.timer-controls {
    display: flex;
    gap: var(--space-md);
    justify-content: center;
}

.timer-btn {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-xl);
}

.timer-btn.play-pause {
    background: linear-gradient(135deg, var(--success-color), #059669);
    color: white;
    box-shadow: var(--shadow-lg);
}

.timer-btn.play-pause:hover {
    transform: scale(1.1);
}

.timer-btn.reset {
    background: var(--surface);
    color: var(--error-color);
    border: 2px solid var(--error-color);
}

.timer-btn.settings {
    background: var(--surface);
    color: var(--text-secondary);
    border: 2px solid var(--border-color);
}

/* Timer Settings */
/* Timer settings - já definido no sistema de cards melhorado */

.timer-settings h3 {
    margin-bottom: var(--space-lg);
    color: var(--primary-color);
}

.setting-group {
    margin-bottom: var(--space-lg);
}

.setting-group label {
    display: block;
    margin-bottom: var(--space-sm);
    font-weight: 500;
    color: var(--text-primary);
}

.slider {
    width: 100%;
    height: 6px;
    border-radius: 3px;
    background: var(--border-color);
    outline: none;
    appearance: none;
    margin-bottom: var(--space-sm);
}

.slider::-webkit-slider-thumb {
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    box-shadow: var(--shadow-md);
}

.slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    border: none;
}

.setting-value {
    font-weight: 600;
    color: var(--primary-color);
    float: right;
}

.setting-group input[type="checkbox"] {
    margin-right: var(--space-sm);
    accent-color: var(--primary-color);
}

.preset-buttons {
    display: flex;
    gap: var(--space-sm);
    margin-top: var(--space-lg);
}

/* Study Session */
/* Study session - já definido no sistema de cards melhorado */

.study-session h3 {
    margin-bottom: var(--space-lg);
    color: var(--primary-color);
}

.form-group {
    margin-bottom: var(--space-lg);
}

.form-group label {
    display: block;
    margin-bottom: var(--space-sm);
    font-weight: 500;
    color: var(--text-primary);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: var(--space-md);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: var(--font-size-base);
    transition: border-color var(--transition-fast);
    background: var(--background-primary);
    color: var(--text-primary);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.quick-actions {
    margin-top: var(--space-xl);
    padding-top: var(--space-xl);
    border-top: 1px solid var(--border-color);
}

.quick-actions h4 {
    margin-bottom: var(--space-md);
    color: var(--text-secondary);
}

.action-buttons {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.action-btn {
    width: 100%;
    padding: var(--space-md);
    background: var(--background-tertiary);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.action-btn:hover {
    background: var(--primary-color);
    color: var(--text-inverse);
    border-color: var(--primary-color);
}

/* Statistics Section - já definida no início do arquivo */

.stats-grid {
    display: grid;
    gap: var(--space-xl);
}

.stats-overview {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-lg);
    margin-bottom: var(--space-xl);
}

/* Stat cards - já definidos no sistema de cards melhorado */

/* Stat icon - já definido no sistema de cards melhorado */

.stat-info h3 {
    font-size: var(--font-size-2xl);
    margin-bottom: var(--space-xs);
    color: var(--primary-color);
}

.stat-info p {
    color: var(--text-secondary);
    margin: 0;
}

/* Charts */
.charts-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--space-lg);
    margin-bottom: var(--space-xl);
}

/* Chart cards - já definidos no sistema de cards melhorado */

.chart-card canvas {
    max-height: 300px;
}

/* Review Schedule */
/* Review schedule - já definido no sistema de cards melhorado */

.review-schedule h3 {
    margin-bottom: var(--space-lg);
    color: var(--primary-color);
}

.calendar-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-lg);
}

.calendar-nav {
    background: none;
    border: none;
    font-size: var(--font-size-lg);
    color: var(--primary-color);
    cursor: pointer;
    padding: var(--space-sm);
    border-radius: var(--border-radius);
    transition: background-color var(--transition-fast);
}

.calendar-nav:hover {
    background: var(--background-secondary);
}

.calendar-days {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: var(--space-sm);
    margin-bottom: var(--space-lg);
}

.calendar-day {
    padding: var(--space-md);
    text-align: center;
    border-radius: var(--border-radius);
    background: var(--background-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
}

.calendar-day:hover {
    background: var(--primary-light);
    color: var(--text-inverse);
}

.calendar-day.has-reviews::after {
    content: '';
    position: absolute;
    top: 4px;
    right: 4px;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--warning-color);
}

.calendar-day.today {
    background: var(--primary-color);
    color: var(--text-inverse);
}

.review-list h4 {
    margin-bottom: var(--space-md);
    color: var(--text-secondary);
}

.review-item {
    padding: var(--space-md);
    background: var(--background-secondary);
    border-radius: var(--border-radius);
    margin-bottom: var(--space-sm);
    border-left: 4px solid var(--warning-color);
}

.review-item h5 {
    margin-bottom: var(--space-xs);
    color: var(--text-primary);
}

.review-item p {
    margin: 0;
    font-size: var(--font-size-sm);
    color: var(--text-tertiary);
}

/* Articles Section - já definida no início do arquivo */

.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: var(--space-xl);
    margin-bottom: var(--space-3xl);
}

/* Article cards - já definidos no sistema de cards melhorado */

.article-card.featured {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 0;
}

.article-image {
    height: 200px;
    overflow: hidden;
    position: relative;
}

.article-card.featured .article-image {
    height: auto;
}

.article-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.article-card:hover .article-image img {
    transform: scale(1.05);
}

.article-content {
    padding: var(--space-xl);
}

.article-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-md);
}

.article-category {
    background: var(--primary-color);
    color: var(--text-inverse);
    padding: var(--space-xs) var(--space-md);
    border-radius: var(--border-radius);
    font-size: var(--font-size-xs);
    font-weight: 600;
    text-transform: uppercase;
}

.article-read-time {
    font-size: var(--font-size-sm);
    color: var(--text-tertiary);
}

.article-content h3 {
    margin-bottom: var(--space-md);
    color: var(--text-primary);
    line-height: 1.4;
}

.article-content p {
    color: var(--text-secondary);
    margin-bottom: var(--space-lg);
}

.article-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    margin-bottom: var(--space-lg);
}

.tag {
    background: var(--background-tertiary);
    color: var(--text-secondary);
    padding: var(--space-xs) var(--space-sm);
    border-radius: var(--border-radius);
    font-size: var(--font-size-xs);
}

.article-link {
    color: var(--primary-color);
    font-weight: 500;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    transition: color var(--transition-fast);
}

.article-link:hover {
    color: var(--primary-dark);
}

.article-link::after {
    content: '→';
    transition: transform var(--transition-fast);
}

.article-link:hover::after {
    transform: translateX(4px);
}

/* Newsletter Signup */
.newsletter-signup {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    border-radius: var(--border-radius-lg);
    padding: var(--space-3xl);
    text-align: center;
    color: var(--text-inverse);
}

.newsletter-content h3 {
    margin-bottom: var(--space-md);
    color: var(--text-inverse);
}

.newsletter-content p {
    margin-bottom: var(--space-xl);
    color: rgba(255, 255, 255, 0.9);
    font-size: var(--font-size-lg);
}

.newsletter-form {
    display: flex;
    gap: var(--space-md);
    max-width: 500px;
    margin: 0 auto var(--space-xl);
}

.newsletter-form input {
    flex: 1;
    padding: var(--space-md);
    border: none;
    border-radius: var(--border-radius);
    font-size: var(--font-size-base);
}

.newsletter-form input:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.3);
}

.newsletter-benefits {
    display: flex;
    justify-content: center;
    gap: var(--space-xl);
    flex-wrap: wrap;
}

.newsletter-benefits .benefit-item {
    color: rgba(255, 255, 255, 0.9);
}

.newsletter-benefits .benefit-item i {
    color: var(--text-inverse);
}

/* Footer - já definido no início do arquivo */

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: var(--space-xl);
    margin-bottom: var(--space-xl);
}

.footer-section h4 {
    margin-bottom: var(--space-lg);
    color: var(--text-inverse);
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    font-size: var(--font-size-xl);
    font-weight: 700;
    margin-bottom: var(--space-lg);
}

.footer-brand i {
    font-size: var(--font-size-2xl);
    color: var(--primary-light);
}

.footer-section p {
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: var(--space-lg);
}

.social-links {
    display: flex;
    gap: var(--space-md);
}

.social-link {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-inverse);
    transition: all var(--transition-fast);
}

.social-link:hover {
    background: var(--primary-color);
    transform: translateY(-2px);
}

.footer-section ul {
    list-style: none;
}

.footer-section li {
    margin-bottom: var(--space-sm);
}

.footer-section a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.footer-section a:hover {
    color: var(--text-inverse);
}

.footer-bottom {
    padding-top: var(--space-xl);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: rgba(255, 255, 255, 0.6);
}

.footer-links {
    display: flex;
    gap: var(--space-lg);
}

.footer-links a {
    color: rgba(255, 255, 255, 0.6);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--text-inverse);
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    z-index: var(--z-modal);
    padding: var(--space-lg);
    overflow-y: auto;
}

.modal.show {
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: var(--surface);
    border-radius: var(--border-radius-lg);
    max-width: 800px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-xl);
}

.modal-header {
    padding: var(--space-xl);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h2 {
    margin: 0;
    color: var(--text-primary);
}

.modal-close {
    background: none;
    border: none;
    font-size: var(--font-size-2xl);
    color: var(--text-tertiary);
    cursor: pointer;
    padding: var(--space-sm);
    border-radius: var(--border-radius);
    transition: all var(--transition-fast);
}

.modal-close:hover {
    background: var(--background-secondary);
    color: var(--text-primary);
}

.modal-body {
    padding: var(--space-xl);
}

/* Settings Modal Specific Styles */
.settings-content {
    max-height: 60vh;
    overflow-y: auto;
    padding-right: 10px;
}

.settings-content .setting-group {
    margin-bottom: var(--space-lg);
    padding: var(--space-md);
    background: var(--surface-alt);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
}

.settings-content .setting-group label {
    display: block;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-sm);
}

.settings-content .slider {
    width: 100%;
    margin: var(--space-sm) 0;
}

.settings-content .setting-value {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 0.9em;
    font-weight: 600;
    min-width: 30px;
    text-align: center;
}

.modal-actions {
    display: flex;
    gap: var(--space-md);
    justify-content: flex-end;
    margin-top: var(--space-xl);
    padding-top: var(--space-lg);
    border-top: 1px solid var(--border-color);
}

.preset-buttons {
    margin: var(--space-lg) 0;
    padding: var(--space-md);
    background: var(--background-alt);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
}

.preset-buttons h4 {
    margin-bottom: var(--space-md);
    color: var(--text-primary);
    font-size: 1.1em;
}

.preset-buttons .btn-preset {
    display: inline-block;
    margin: 5px;
    padding: var(--space-sm) var(--space-md);
    background: var(--surface);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    color: var(--text-primary);
    text-decoration: none;
    transition: all 0.3s ease;
    font-size: 0.9em;
}

.preset-buttons .btn-preset:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.preset-buttons .btn-preset i {
    margin-right: 5px;
}

/* Dark Mode Styles */
/* ===== MODO ESCURO MELHORADO ===== */
.dark-mode {
    --background: #0f1419;
    --background-alt: #1a1f26;
    --surface: rgba(26, 31, 38, 0.95);
    --surface-alt: rgba(42, 48, 58, 0.9);
    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    --border-color: rgba(71, 85, 105, 0.3);
    --primary: #4dabf7;
    --primary-dark: #339af0;
    --secondary: #64748b;
    --accent: #ffd43b;
    --success: #51cf66;
    --warning: #ffd43b;
    --error: #ff6b6b;
}

/* Background geral do dark mode */
.dark-mode body {
    background: linear-gradient(135deg, #0f1419 0%, #1a1f26 100%);
    color: var(--text-primary);
}

.dark-mode .main {
    background: linear-gradient(135deg, 
        rgba(15, 20, 25, 0.8) 0%, 
        rgba(26, 31, 38, 0.9) 50%, 
        rgba(42, 48, 58, 0.8) 100%);
}

.dark-mode .main::before {
    background-image: 
        radial-gradient(circle at 20% 20%, rgba(77, 171, 247, 0.08) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(255, 212, 59, 0.06) 0%, transparent 50%),
        radial-gradient(circle at 40% 60%, rgba(81, 207, 102, 0.04) 0%, transparent 50%);
}

/* Cards no dark mode */
.dark-mode .card,
.dark-mode .stat-card,
.dark-mode .chart-card,
.dark-mode .about-card,
.dark-mode .article-card,
.dark-mode .timer-display,
.dark-mode .study-session,
.dark-mode .timer-settings,
.dark-mode .review-schedule {
    background: rgba(26, 31, 38, 0.95);
    border: 1px solid rgba(71, 85, 105, 0.3);
    box-shadow: 
        0 2px 12px rgba(0, 0, 0, 0.3),
        0 6px 30px rgba(0, 0, 0, 0.2),
        0 0 0 1px rgba(248, 250, 252, 0.05);
    backdrop-filter: blur(12px);
}

.dark-mode .card:hover,
.dark-mode .stat-card:hover,
.dark-mode .chart-card:hover,
.dark-mode .about-card:hover,
.dark-mode .article-card:hover {
    box-shadow: 
        0 8px 25px rgba(0, 0, 0, 0.4),
        0 12px 40px rgba(0, 0, 0, 0.25),
        0 0 0 1px rgba(248, 250, 252, 0.1);
}

/* Seções no dark mode */
.dark-mode .hero {
    background: linear-gradient(135deg, 
        rgba(15, 20, 25, 0.95) 0%, 
        rgba(26, 31, 38, 0.90) 50%,
        rgba(42, 48, 58, 0.85) 100%);
    border-bottom: 1px solid rgba(77, 171, 247, 0.1);
}

.dark-mode .about {
    background: linear-gradient(135deg, 
        rgba(26, 31, 38, 0.8) 0%, 
        rgba(15, 20, 25, 0.9) 100%);
    border-top: 1px solid rgba(77, 171, 247, 0.08);
    border-bottom: 1px solid rgba(77, 171, 247, 0.08);
}

.dark-mode .timer-section {
    background: linear-gradient(135deg, 
        rgba(15, 20, 25, 0.95) 0%, 
        rgba(26, 31, 38, 0.90) 50%,
        rgba(42, 48, 58, 0.85) 100%);
    box-shadow: 
        inset 0 1px 0 rgba(248, 250, 252, 0.05),
        0 2px 30px rgba(77, 171, 247, 0.08);
}

.dark-mode .stats-section {
    background: linear-gradient(135deg, 
        rgba(26, 31, 38, 0.8) 0%, 
        rgba(42, 48, 58, 0.9) 100%);
    border-top: 1px solid rgba(77, 171, 247, 0.08);
}

.dark-mode .articles-section {
    background: linear-gradient(135deg, 
        rgba(15, 20, 25, 0.9) 0%, 
        rgba(26, 31, 38, 0.8) 100%);
}

/* Header no dark mode */
.dark-mode .header {
    background: rgba(15, 20, 25, 0.95);
    border-bottom: 1px solid rgba(71, 85, 105, 0.3);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.dark-mode .nav-link {
    color: var(--text-secondary);
}

.dark-mode .nav-link:hover,
.dark-mode .nav-link.active {
    color: var(--primary);
}

/* Timer */
.dark-mode .timer-container {
    background: linear-gradient(135deg, #2d2d2d 0%, #1a1a1a 100%);
    border: 1px solid var(--border-color);
}

.dark-mode .timer-display {
    color: var(--text-primary);
    text-shadow: 0 0 20px rgba(77, 171, 247, 0.3);
}

.dark-mode .timer-controls button {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    border: 1px solid var(--primary-dark);
}

.dark-mode .timer-controls button:hover {
    background: linear-gradient(135deg, var(--primary-dark) 0%, #1c7ed6 100%);
}

/* Cards e Estatísticas */
.dark-mode .stat-card {
    background: linear-gradient(135deg, #383838 0%, #2d2d2d 100%);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
}

.dark-mode .stat-card h3 {
    color: var(--text-primary);
}

.dark-mode .stat-card .stat-value {
    color: var(--primary);
}

/* Configurações */
.dark-mode .config-section {
    background: var(--surface);
    border: 1px solid var(--border-color);
}

.dark-mode .config-item label {
    color: var(--text-primary);
}

.dark-mode .config-item input,
.dark-mode .config-item select {
    background: var(--surface-alt);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
}

.dark-mode .config-item input:focus,
.dark-mode .config-item select:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 2px rgba(77, 171, 247, 0.2);
}

/* Modals */
.dark-mode .modal-content {
    background: var(--surface);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
}

.dark-mode .modal-header {
    border-bottom: 1px solid var(--border-color);
}

.dark-mode .modal-title {
    color: var(--text-primary);
}

.dark-mode .close {
    color: var(--text-secondary);
}

.dark-mode .close:hover {
    color: var(--text-primary);
}

/* Botões */
.dark-mode .btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    border-color: var(--primary-dark);
}

.dark-mode .btn-primary:hover {
    background: linear-gradient(135deg, var(--primary-dark) 0%, #1c7ed6 100%);
}

.dark-mode .btn-secondary {
    background: var(--secondary);
    border-color: var(--secondary);
    color: var(--text-primary);
}

.dark-mode .btn-success {
    background: var(--success);
    border-color: var(--success);
}

.dark-mode .btn-warning {
    background: var(--warning);
    border-color: var(--warning);
    color: #000;
}

.dark-mode .btn-danger {
    background: var(--error);
    border-color: var(--error);
}

/* Artigos */
.dark-mode .article-card {
    background: var(--surface);
    border: 1px solid var(--border-color);
}

.dark-mode .article-card h4 {
    color: var(--text-primary);
}

.dark-mode .article-card p {
    color: var(--text-secondary);
}

.dark-mode .article-link {
    color: var(--primary);
}

.dark-mode .article-link:hover {
    color: var(--primary-dark);
}

/* Revisões */
.dark-mode .review-item {
    background: var(--surface);
    border: 1px solid var(--border-color);
}

.dark-mode .review-item h4 {
    color: var(--text-primary);
}

.dark-mode .review-item p {
    color: var(--text-secondary);
}

/* Ações Rápidas */
.dark-mode .quick-actions {
    background: var(--surface);
    border: 1px solid var(--border-color);
}

.dark-mode .action-btn {
    background: var(--surface-alt);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
}

.dark-mode .action-btn:hover {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

/* Gráficos */
.dark-mode .chart-container {
    background: var(--surface);
    border: 1px solid var(--border-color);
}

/* Scrollbar personalizada */
.dark-mode ::-webkit-scrollbar {
    width: 8px;
}

.dark-mode ::-webkit-scrollbar-track {
    background: var(--surface-alt);
}

.dark-mode ::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

.dark-mode ::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

/* Inputs específicos */
.dark-mode .form-control {
    background: var(--surface-alt);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
}

.dark-mode .form-control:focus {
    background: var(--surface-alt);
    border-color: var(--primary);
    color: var(--text-primary);
    box-shadow: 0 0 0 2px rgba(77, 171, 247, 0.2);
}

/* Checkbox e switch */
.dark-mode .switch {
    background: var(--surface-alt);
}

.dark-mode .switch input:checked + .slider {
    background: var(--primary);
}

.dark-mode .slider:before {
    background: white;
}

/* Notifications */
.notification-container {
    position: fixed;
    top: 100px;
    right: var(--space-lg);
    z-index: var(--z-notification);
    max-width: 400px;
}

.notification {
    background: var(--surface);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    padding: var(--space-lg);
    margin-bottom: var(--space-md);
    border-left: 4px solid var(--primary-color);
    animation: slideInRight 0.3s ease-out;
    position: relative;
}

.notification.success { border-left-color: var(--success-color); }
.notification.warning { border-left-color: var(--warning-color); }
.notification.error { border-left-color: var(--error-color); }

.notification-title {
    font-weight: 600;
    margin-bottom: var(--space-xs);
}

.notification-message {
    color: var(--text-secondary);
    margin: 0;
}

.notification-close {
    position: absolute;
    top: var(--space-sm);
    right: var(--space-sm);
    background: none;
    border: none;
    color: var(--text-tertiary);
    cursor: pointer;
    padding: var(--space-xs);
}

@keyframes slideInRight {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* Responsive Design */
@media (max-width: 1024px) {
    .timer-container {
        grid-template-columns: 1fr;
        gap: var(--space-xl);
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .footer-content {
        grid-template-columns: 1fr 1fr;
        gap: var(--space-xl);
    }
}

@media (max-width: 768px) {
    .container {
        padding: 0 var(--space-md);
    }
    
    .nav-links {
        display: none;
    }
    
    .nav-toggle {
        display: block;
    }
    
    .hero-title {
        font-size: var(--font-size-3xl);
    }
    
    .hero-cta {
        justify-content: center;
    }
    
    .clock-face {
        width: 250px;
        height: 250px;
    }
    
    .about-grid {
        grid-template-columns: 1fr;
    }
    
    .article-card.featured {
        grid-template-columns: 1fr;
    }
    
    .newsletter-form {
        flex-direction: column;
    }
    
    .newsletter-benefits {
        flex-direction: column;
        align-items: center;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: var(--space-md);
        text-align: center;
    }
    
    .methodology-flow {
        flex-direction: column;
    }
    
    .flow-arrow {
        transform: rotate(90deg);
    }
}

@media (max-width: 480px) {
    .hero {
        padding: var(--space-xl) 0;
    }
    
    .section-header h2 {
        font-size: var(--font-size-2xl);
    }
    
    .timer-circle {
        width: 200px;
        height: 200px;
    }
    
    .timer-time {
        font-size: var(--font-size-2xl);
    }
    
    .stats-overview {
        grid-template-columns: 1fr;
    }
    
    .charts-container {
        grid-template-columns: 1fr;
    }
    
    .calendar-days {
        grid-template-columns: repeat(7, 1fr);
        gap: 2px;
    }
    
    .calendar-day {
        padding: var(--space-sm);
        font-size: var(--font-size-sm);
    }
}

/* Print Styles */
@media print {
    .header,
    .footer,
    .timer-controls,
    .nav-toggle {
        display: none;
    }
    
    .main {
        margin-top: 0;
    }
    
    * {
        background: white !important;
        color: black !important;
    }
}

/* Accessibility Improvements */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
    :root {
        --primary-color: #000080;
        --text-primary: #000000;
        --text-secondary: #333333;
        --border-color: #000000;
        --background-primary: #ffffff;
        --surface: #ffffff;
    }
}

/* Focus Styles */
*:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

button:focus,
input:focus,
textarea:focus,
select:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}

/* Selection Styles */
::selection {
    background: var(--primary-light);
    color: var(--text-inverse);
}

::-moz-selection {
    background: var(--primary-light);
    color: var(--text-inverse);
}

/* ===== SISTEMA DE ARTIGOS ===== */
.article-header {
    padding-bottom: 20px;
    border-bottom: 2px solid var(--border-color);
    margin-bottom: 25px;
}

.article-meta {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    color: var(--text-secondary);
    font-size: 0.9em;
}

.article-author,
.article-read-time {
    display: flex;
    align-items: center;
    gap: 5px;
}

.article-content {
    line-height: 1.8;
    font-size: 1.05em;
    color: var(--text-primary);
}

.article-content h3 {
    color: var(--primary);
    margin-top: 30px;
    margin-bottom: 15px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border-color);
}

.article-content h4 {
    color: var(--text-primary);
    margin-top: 25px;
    margin-bottom: 12px;
    font-weight: 600;
}

.article-content p {
    margin-bottom: 16px;
    text-align: justify;
}

.article-content ul,
.article-content ol {
    margin-bottom: 20px;
    padding-left: 25px;
}

.article-content li {
    margin-bottom: 8px;
    line-height: 1.6;
}

.article-content strong {
    color: var(--primary);
    font-weight: 600;
}

.article-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
    background: var(--surface-alt);
    border-radius: 8px;
    overflow: hidden;
}

.article-content th,
.article-content td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.article-content th {
    background: var(--primary);
    color: white;
    font-weight: 600;
}

.article-content tr:last-child td {
    border-bottom: none;
}

.article-content code {
    background: var(--surface-alt);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 0.9em;
    color: var(--primary);
}

.article-footer {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 2px solid var(--border-color);
    text-align: center;
}

.article-footer em {
    color: var(--text-secondary);
    font-style: italic;
}

.article-footer .btn {
    margin-top: 15px;
    padding: 12px 30px;
    font-size: 1.1em;
    font-weight: 600;
}

/* Estilos para modo escuro nos artigos */
.dark-mode .article-header {
    border-bottom-color: var(--border-color);
}

.dark-mode .article-content h3 {
    color: var(--primary);
    border-bottom-color: var(--border-color);
}

.dark-mode .article-content h4 {
    color: var(--text-primary);
}

.dark-mode .article-content table {
    background: var(--surface-alt);
}

.dark-mode .article-content th {
    background: var(--primary);
}

.dark-mode .article-content td {
    border-bottom-color: var(--border-color);
}

.dark-mode .article-content code {
    background: var(--surface-alt);
    color: var(--primary);
}

.dark-mode .article-footer {
    border-top-color: var(--border-color);
}

/* Responsividade para artigos */
@media (max-width: 768px) {
    .article-meta {
        flex-direction: column;
        gap: 10px;
    }
    
    .article-content {
        font-size: 1em;
    }
    
    .article-content table {
        font-size: 0.9em;
    }
    
    .article-content th,
    .article-content td {
        padding: 8px 10px;
    }
}

/* ===== RESPONSIVIDADE GLOBAL AVANÇADA ===== */

/* Desktop ultra-large (1600px+) */
@media (min-width: 1600px) {
    :root {
        --space-xs: 4px;
        --space-sm: 8px;
        --space-md: 16px;
        --space-lg: 24px;
        --space-xl: 32px;
        --space-2xl: 48px;
        --space-3xl: 64px;
        
        --font-size-xs: 12px;
        --font-size-sm: 14px;
        --font-size-base: 16px;
        --font-size-lg: 18px;
        --font-size-xl: 20px;
        --font-size-2xl: 24px;
        --font-size-3xl: 30px;
        --font-size-4xl: 36px;
        --font-size-5xl: 48px;
    }
}

/* Tablet portrait (768px - 1023px) */
@media (max-width: 1023px) and (min-width: 768px) {
    :root {
        --space-xs: 3px;
        --space-sm: 6px;
        --space-md: 12px;
        --space-lg: 18px;
        --space-xl: 24px;
        --space-2xl: 36px;
        --space-3xl: 48px;
        
        --font-size-xs: 11px;
        --font-size-sm: 13px;
        --font-size-base: 15px;
        --font-size-lg: 17px;
        --font-size-xl: 19px;
        --font-size-2xl: 22px;
        --font-size-3xl: 26px;
        --font-size-4xl: 30px;
        --font-size-5xl: 36px;
    }
}

/* Mobile large (481px - 767px) */
@media (max-width: 767px) and (min-width: 481px) {
    :root {
        --space-xs: 2px;
        --space-sm: 4px;
        --space-md: 8px;
        --space-lg: 12px;
        --space-xl: 16px;
        --space-2xl: 24px;
        --space-3xl: 32px;
        
        --font-size-xs: 10px;
        --font-size-sm: 12px;
        --font-size-base: 14px;
        --font-size-lg: 16px;
        --font-size-xl: 18px;
        --font-size-2xl: 20px;
        --font-size-3xl: 24px;
        --font-size-4xl: 28px;
        --font-size-5xl: 32px;
    }
}

/* Mobile small (até 480px) */
@media (max-width: 480px) {
    :root {
        --space-xs: 2px;
        --space-sm: 4px;
        --space-md: 6px;
        --space-lg: 8px;
        --space-xl: 12px;
        --space-2xl: 16px;
        --space-3xl: 24px;
        
        --font-size-xs: 10px;
        --font-size-sm: 11px;
        --font-size-base: 13px;
        --font-size-lg: 15px;
        --font-size-xl: 17px;
        --font-size-2xl: 19px;
        --font-size-3xl: 22px;
        --font-size-4xl: 26px;
        --font-size-5xl: 30px;
        
        --border-radius: 6px;
        --border-radius-lg: 12px;
        --border-radius-xl: 16px;
    }
    
    .card,
    .stat-card,
    .chart-card,
    .about-card,
    .article-card {
        padding: var(--space-md);
    }
    
    .main {
        margin-top: 60px;
    }
    
    .hero,
    .timer-section,
    .stats-section,
    .articles-section,
    .about {
        padding: var(--space-xl) 0;
    }
    
    .footer {
        padding: var(--space-xl) 0 var(--space-lg);
    }
}

/* Acessibilidade para dispositivos com pouco espaço em altura */
@media (max-height: 600px) {
    .timer-display {
        padding: var(--space-md);
        gap: var(--space-md);
    }
    
    .hero,
    .timer-section,
    .stats-section,
    .articles-section,
    .about {
        padding: var(--space-lg) 0;
    }
    
    .modal-content {
        max-height: 90vh;
        overflow-y: auto;
    }
}

/* Modo landscape em tablets */
@media (max-width: 1024px) and (orientation: landscape) {
    .timer-container {
        grid-template-columns: 1fr 1fr 1fr;
        grid-template-areas:
            "timer-display study-session quick-stats"
            "schedule schedule schedule";
        gap: var(--space-md);
    }
    
    .timer-display {
        padding: var(--space-md);
    }
}

/* ===== UTILITÁRIOS RESPONSIVOS ===== */

/* Classes de utilidade para spacing responsivo */
.mt-responsive { margin-top: var(--space-lg); }
.mb-responsive { margin-bottom: var(--space-lg); }
.p-responsive { padding: var(--space-lg); }

@media (max-width: 768px) {
    .mt-responsive { margin-top: var(--space-md); }
    .mb-responsive { margin-bottom: var(--space-md); }
    .p-responsive { padding: var(--space-md); }
}

/* Classes para controle de grid responsivo */
.grid-responsive {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-lg);
}

@media (max-width: 768px) {
    .grid-responsive {
        grid-template-columns: 1fr;
        gap: var(--space-md);
    }
}

/* Visibilidade responsiva */
.hide-mobile { display: block; }
.show-mobile { display: none; }

@media (max-width: 768px) {
    .hide-mobile { display: none; }
    .show-mobile { display: block; }
}

/* Texto responsivo */
.text-responsive {
    font-size: var(--font-size-base);
    line-height: 1.6;
}

@media (max-width: 768px) {
    .text-responsive {
        font-size: var(--font-size-sm);
        line-height: 1.5;
    }
}

/* ===== TEMA ESCURO PARA UTILITÁRIOS ===== */

.dark-mode .grid-responsive {
    gap: var(--space-lg);
}

@media (max-width: 768px) {
    .dark-mode .grid-responsive {
        gap: var(--space-md);
    }
}

/* ===== CALL TO ACTION PARA ARTIGOS ===== */

.articles-cta {
    padding: var(--space-3xl) 0;
    background: var(--gradient-card);
    border-top: 1px solid var(--border-secondary);
    text-align: center;
}

.cta-content {
    max-width: 600px;
    margin: 0 auto;
}

.cta-content h2 {
    font-size: var(--font-size-3xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-lg);
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.cta-content p {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    margin-bottom: var(--space-2xl);
    line-height: 1.6;
}

.btn-lg {
    padding: var(--space-lg) var(--space-2xl);
    font-size: var(--font-size-lg);
    border-radius: var(--border-radius-lg);
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    box-shadow: var(--shadow-medium);
    transition: all var(--transition-normal);
}

.btn-lg:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-heavy);
}

@media (max-width: 768px) {
    .articles-cta {
        padding: var(--space-2xl) 0;
    }
    
    .cta-content h2 {
        font-size: var(--font-size-2xl);
    }
    
    .cta-content p {
        font-size: var(--font-size-base);
    }
    
    .btn-lg {
        padding: var(--space-md) var(--space-xl);
        font-size: var(--font-size-base);
        width: 100%;
        justify-content: center;
    }
}