/* Importación de la fuente */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

/* Variables CSS para temas */
:root {
    /* Modo claro */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #e2e8f0;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --accent-primary: #3b82f6;
    --accent-secondary: #1d4ed8;
    --success: #10b981;
    --success-bg: #d1fae5;
    --success-border: #34d399;
    --error: #ef4444;
    --error-bg: #fee2e2;
    --warning: #f59e0b;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
}

/* Modo oscuro */
[data-theme="dark"] {
    --bg-primary: #1e293b;
    --bg-secondary: #0f172a;
    --bg-tertiary: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;
    --accent-primary: #60a5fa;
    --accent-secondary: #3b82f6;
    --success: #22c55e;
    --success-bg: #064e3b;
    --success-border: #059669;
    --error: #f87171;
    --error-bg: #7f1d1d;
    --warning: #fbbf24;
    --border-color: #475569;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.3);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.3), 0 2px 4px -2px rgb(0 0 0 / 0.3);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.3), 0 4px 6px -4px rgb(0 0 0 / 0.3);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.3), 0 8px 10px -6px rgb(0 0 0 / 0.3);
}

/* Reset y estilos base */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Header */
.header {
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: 4rem;
}

.logo h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-primary);
    margin: 0;
}

.navigation {
    display: flex;
    gap: 0.5rem;
}

.nav-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 0.5rem;
    background: transparent;
    color: var(--text-secondary);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
}

.nav-btn:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.nav-btn.active {
    background: var(--accent-primary);
    color: white;
    box-shadow: var(--shadow-md);
}

.nav-icon {
    font-size: 1.2rem;
}

.header-controls {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.theme-toggle {
    padding: 0.75rem;
    border: none;
    border-radius: 0.5rem;
    background: var(--bg-tertiary);
    color: var(--text-primary);
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-toggle:hover {
    background: var(--accent-primary);
    color: white;
    transform: scale(1.05);
}

.theme-icon {
    font-size: 1.2rem;
}

/* Main Content */
.main-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

/* Container */
.container {
    background: var(--bg-primary);
    border-radius: 1rem;
    box-shadow: var(--shadow-lg);
    padding: 2rem;
    margin-bottom: 2rem;
    border: 1px solid var(--border-color);
}

/* Score Tracker */
.score-tracker {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--bg-secondary);
    padding: 1rem 1.5rem;
    border-radius: 0.75rem;
    margin-bottom: 2rem;
    border: 1px solid var(--border-color);
}

.scores {
    display: flex;
    gap: 1.5rem;
}

.scores span {
    font-weight: 600;
    color: var(--text-secondary);
}

#correct-count {
    color: var(--success);
}

#incorrect-count {
    color: var(--error);
}

/* Questions */
#question-header {
    margin-bottom: 2rem;
}

#question-text {
    font-size: 1.4rem;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.5;
    text-align: center;
}

/* Answer Buttons */
.btn-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
    margin-bottom: 2rem;
    width: 100%;
}

.answer-btn {
    padding: 1rem 1.5rem !important;
    border: 2px solid var(--border-color) !important;
    border-radius: 0.75rem !important;
    background: var(--bg-primary) !important;
    color: var(--text-primary) !important;
    font-size: 1rem !important;
    font-weight: 500 !important;
    cursor: pointer;
    transition: all 0.3s ease;
    text-align: left !important;
    min-height: 4rem;
    display: flex !important;
    align-items: center !important;
    justify-content: flex-start !important;
    width: 100% !important;
    max-width: none !important;
    box-sizing: border-box !important;
    box-shadow: var(--shadow-sm);
}

.answer-btn:hover:not(.correct):not(.incorrect):not(:disabled) {
    border-color: var(--accent-primary);
    background: var(--bg-secondary);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

/* Estilos específicos para modo oscuro */
[data-theme="dark"] .answer-btn {
    background: var(--bg-tertiary);
    border-color: var(--border-color);
    box-shadow: var(--shadow-md);
}

[data-theme="dark"] .answer-btn:hover:not(.correct):not(.incorrect):not(:disabled) {
    background: var(--bg-secondary);
    border-color: var(--accent-primary);
}

.answer-btn.correct {
    background: var(--success-bg) !important;
    border-color: var(--success-border) !important;
    color: var(--success) !important;
    font-weight: 600;
    transform: none !important;
}

.answer-btn.incorrect {
    background: var(--error-bg) !important;
    border-color: var(--error) !important;
    color: var(--error) !important;
    font-weight: 600;
    transform: none !important;
}

/* Controls */
.controls {
    display: flex;
    justify-content: center;
}

.btn {
    padding: 0.875rem 2rem;
    border: none;
    border-radius: 0.5rem;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.next-btn {
    background: var(--accent-primary);
    color: white;
}

.next-btn:hover {
    background: var(--accent-secondary);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.restart-btn {
    background: var(--success);
    color: white;
}

.restart-btn:hover {
    background: #059669;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

/* Results */
#results-container h2 {
    font-size: 2rem;
    color: var(--text-primary);
    text-align: center;
    margin-bottom: 1rem;
}

#results-container p {
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.final-score {
    background: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: 0.75rem;
    margin-bottom: 2rem;
    border: 1px solid var(--border-color);
}

.final-score p {
    margin-bottom: 0.5rem;
    font-weight: 500;
    text-align: left;
}

.percentage {
    text-align: center;
    margin-bottom: 2rem;
}

.percentage h3 {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

#percentage-summary {
    font-size: 3rem;
    font-weight: 700;
    color: var(--accent-primary);
}

/* Study Mode */
.study-header {
    text-align: center;
    margin-bottom: 2rem;
}

.study-header h2 {
    font-size: 2rem;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
}

.study-controls {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
    align-items: center;
}

.search-input {
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: 0.5rem;
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 1rem;
    width: 300px;
    max-width: 100%;
    outline: none;
    transition: border-color 0.3s ease;
}

.search-input:focus {
    border-color: var(--accent-primary);
}

.search-input::placeholder {
    color: var(--text-muted);
}

.questions-list {
    max-width: 900px;
    margin: 0 auto;
}

.question-card {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    box-shadow: var(--shadow-md);
    margin-bottom: 1.5rem;
    padding: 1.5rem;
    transition: all 0.3s ease;
}

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

.question-number {
    display: inline-block;
    background: var(--accent-primary);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 1rem;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.question-text {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1rem;
    font-size: 1.1rem;
    line-height: 1.5;
}

.answer-option {
    padding: 0.75rem 1rem;
    margin-bottom: 0.5rem;
    border-radius: 0.5rem;
    transition: all 0.3s ease;
    border: 1px solid transparent;
}

.answer-option.correct {
    background: var(--success-bg);
    border-color: var(--success-border);
    color: var(--success);
    font-weight: 600;
}

.answer-option.incorrect {
    color: var(--text-secondary);
    background: var(--bg-secondary);
}

/* Utilities */
.hide {
    display: none;
}

/* Responsive Design */
@media (max-width: 768px) {
    .header-content {
        padding: 0 1rem;
        flex-direction: column;
        gap: 1rem;
        min-height: auto;
        padding-top: 1rem;
        padding-bottom: 1rem;
    }
    
    .logo {
        order: 1;
    }
    
    .navigation {
        order: 2;
        width: 100%;
        justify-content: center;
    }
    
    .header-controls {
        order: 3;
        position: absolute;
        top: 1rem;
        right: 1rem;
    }
    
    .nav-btn {
        flex: 1;
        justify-content: center;
        max-width: 150px;
    }
    
    .main-content {
        padding: 1rem;
    }
    
    .container {
        padding: 1.5rem;
    }
    
    .score-tracker {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
    
    .scores {
        justify-content: center;
    }
    
    #question-text {
        font-size: 1.2rem;
    }
    
    .answer-btn {
        width: 100%;
        margin-bottom: 0.5rem;
    }
    
    .btn-grid {
        gap: 0.75rem;
        grid-template-columns: 1fr;
        width: 100%;
    }
    
    .study-controls {
        flex-direction: column;
        align-items: stretch;
    }
    
    .search-input {
        width: 100%;
    }
    
    .btn {
        width: 100%;
        max-width: 200px;
        margin: 0 auto;
    }
    
    .answer-btn {
        width: 100% !important;
        max-width: none !important;
        margin: 0 !important;
    }
}

@media (max-width: 480px) {
    .logo h1 {
        font-size: 1.25rem;
    }
    
    .nav-btn {
        padding: 0.6rem 1rem;
        font-size: 0.9rem;
    }
    
    .answer-btn {
        padding: 0.875rem 1rem;
        min-height: 3.5rem;
        font-size: 0.95rem;
        width: 100%;
        margin-bottom: 0.5rem;
    }
    
    .btn-grid {
        gap: 0.75rem;
        grid-template-columns: 1fr;
        width: 100%;
    }
    
    #percentage-summary {
        font-size: 2.5rem;
    }
}