/* ============================================
   STM32 Driver Mentor - Styles
   A dark, technical aesthetic inspired by IDEs
   ============================================ */

:root {
    /* Color Palette - Inspired by embedded/hardware aesthetics */
    --bg-primary: #0a0e14;
    --bg-secondary: #0d1117;
    --bg-tertiary: #151b23;
    --bg-card: #161b22;
    --bg-hover: #1c2128;
    
    --border-primary: #30363d;
    --border-highlight: #3fb950;
    
    --text-primary: #e6edf3;
    --text-secondary: #8b949e;
    --text-muted: #6e7681;
    
    /* Accent Colors - Circuit board inspired */
    --accent-green: #3fb950;
    --accent-green-dim: #238636;
    --accent-blue: #58a6ff;
    --accent-orange: #f0883e;
    --accent-red: #f85149;
    --accent-purple: #a371f7;
    --accent-cyan: #39c5cf;
    --accent-yellow: #d29922;
    
    /* Syntax Highlighting */
    --syntax-keyword: #ff7b72;
    --syntax-string: #a5d6ff;
    --syntax-function: #d2a8ff;
    --syntax-comment: #8b949e;
    --syntax-number: #79c0ff;
    --syntax-type: #7ee787;
    
    /* Typography */
    --font-primary: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    
    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 400ms ease;
}

/* Reset & Base */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

/* Background Pattern - Circuit Board Effect */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        linear-gradient(90deg, transparent 49.5%, var(--border-primary) 49.5%, var(--border-primary) 50.5%, transparent 50.5%),
        linear-gradient(0deg, transparent 49.5%, var(--border-primary) 49.5%, var(--border-primary) 50.5%, transparent 50.5%);
    background-size: 60px 60px;
    opacity: 0.03;
    pointer-events: none;
    z-index: -1;
}

/* App Container */
.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* ============================================
   Header
   ============================================ */
.header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-md) var(--space-xl);
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-primary);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.logo-icon {
    width: 36px;
    height: 36px;
    color: var(--accent-green);
    animation: pulse-glow 3s ease-in-out infinite;
}

@keyframes pulse-glow {
    0%, 100% { filter: drop-shadow(0 0 2px var(--accent-green)); }
    50% { filter: drop-shadow(0 0 8px var(--accent-green)); }
}

.logo-text {
    font-size: 1.25rem;
    font-weight: 600;
    background: linear-gradient(135deg, var(--accent-green), var(--accent-cyan));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.nav-btn {
    padding: var(--space-sm) var(--space-md);
    background: transparent;
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    font-family: var(--font-primary);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

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

.nav-btn.active {
    color: var(--accent-green);
    border-color: var(--accent-green-dim);
    background: rgba(63, 185, 80, 0.1);
}

/* ============================================
   Main Content
   ============================================ */
.main-content {
    flex: 1;
    padding: var(--space-xl);
    max-width: 1400px;
    margin: 0 auto;
    width: 100%;
}

.view {
    display: none;
    animation: fadeIn 0.3s ease;
}

.view.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ============================================
   Home View - Hero & Driver Cards
   ============================================ */
.hero {
    text-align: center;
    margin-bottom: var(--space-2xl);
    padding: var(--space-2xl) 0;
}

.hero-title {
    font-size: 2.75rem;
    font-weight: 700;
    margin-bottom: var(--space-md);
    background: linear-gradient(135deg, var(--text-primary) 0%, var(--accent-green) 50%, var(--accent-cyan) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradient-shift 8s ease infinite;
    background-size: 200% 200%;
}

@keyframes gradient-shift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.hero-subtitle {
    font-size: 1.15rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* Driver Grid */
.driver-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--space-lg);
}

.driver-card {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    cursor: pointer;
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.driver-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-green), var(--accent-cyan));
    transform: scaleX(0);
    transform-origin: left;
    transition: transform var(--transition-normal);
}

.driver-card:hover {
    border-color: var(--accent-green-dim);
    transform: translateY(-4px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.3), 0 0 20px rgba(63, 185, 80, 0.1);
}

/* Featured Card (MCU Header) */
.driver-card.featured {
    border: 2px solid var(--accent-purple);
    background: linear-gradient(135deg, var(--bg-card) 0%, rgba(163, 113, 247, 0.08) 100%);
}

.driver-card.featured::before {
    background: linear-gradient(90deg, var(--accent-purple), var(--accent-cyan));
    transform: scaleX(1);
}

.driver-card.featured:hover {
    border-color: var(--accent-purple);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.3), 0 0 30px rgba(163, 113, 247, 0.2);
}

.card-badge {
    position: absolute;
    top: var(--space-md);
    right: var(--space-md);
    background: var(--accent-purple);
    color: white;
    font-size: 0.7rem;
    font-weight: 600;
    padding: 4px 10px;
    border-radius: 20px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    animation: pulse-badge 2s ease-in-out infinite;
}

@keyframes pulse-badge {
    0%, 100% { transform: scale(1); box-shadow: 0 0 0 0 rgba(163, 113, 247, 0.5); }
    50% { transform: scale(1.05); box-shadow: 0 0 10px 3px rgba(163, 113, 247, 0.3); }
}

/* MCU Icon */
.mcu-icon {
    background: linear-gradient(135deg, rgba(163, 113, 247, 0.15), rgba(57, 197, 207, 0.15));
}

.mcu-icon svg {
    color: var(--accent-purple);
}

/* C Programming Card */
.driver-card.prerequisite {
    border: 2px solid var(--accent-cyan);
    background: linear-gradient(135deg, var(--bg-card) 0%, rgba(57, 197, 207, 0.08) 100%);
}

.driver-card.prerequisite::before {
    background: linear-gradient(90deg, var(--accent-cyan), var(--accent-blue));
    transform: scaleX(1);
}

.driver-card.prerequisite:hover {
    border-color: var(--accent-cyan);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.3), 0 0 30px rgba(57, 197, 207, 0.2);
}

.prereq-badge {
    background: var(--accent-cyan) !important;
}

.c-icon {
    background: linear-gradient(135deg, rgba(57, 197, 207, 0.15), rgba(88, 166, 255, 0.15));
}

.c-icon svg {
    color: var(--accent-cyan);
}

.driver-card:hover::before {
    transform: scaleX(1);
}

.card-icon {
    width: 56px;
    height: 56px;
    padding: var(--space-sm);
    border-radius: var(--radius-md);
    margin-bottom: var(--space-md);
    transition: all var(--transition-normal);
}

.gpio-icon { background: rgba(63, 185, 80, 0.15); color: var(--accent-green); }
.spi-icon { background: rgba(88, 166, 255, 0.15); color: var(--accent-blue); }
.i2c-icon { background: rgba(163, 113, 247, 0.15); color: var(--accent-purple); }
.usart-icon { background: rgba(240, 136, 62, 0.15); color: var(--accent-orange); }
.rtos-icon { background: rgba(57, 197, 207, 0.15); color: var(--accent-cyan); }
.interview-icon { background: rgba(210, 153, 34, 0.15); color: var(--accent-yellow); }

.driver-card:hover .card-icon {
    transform: scale(1.1);
}

.card-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--space-sm);
    color: var(--text-primary);
}

.card-desc {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-md);
    line-height: 1.5;
}

.card-meta {
    display: flex;
    gap: var(--space-md);
    margin-bottom: var(--space-md);
}

.difficulty, .duration {
    font-size: 0.75rem;
    font-weight: 500;
    padding: var(--space-xs) var(--space-sm);
    border-radius: var(--radius-sm);
}

.difficulty.beginner {
    background: rgba(63, 185, 80, 0.15);
    color: var(--accent-green);
}

.difficulty.intermediate {
    background: rgba(210, 153, 34, 0.15);
    color: var(--accent-yellow);
}

.difficulty.advanced {
    background: rgba(248, 81, 73, 0.15);
    color: var(--accent-red);
}

.difficulty.foundation {
    background: rgba(163, 113, 247, 0.15);
    color: var(--accent-purple);
    font-weight: 600;
}

.difficulty.prerequisite-level {
    background: rgba(57, 197, 207, 0.15);
    color: var(--accent-cyan);
    font-weight: 600;
}

.difficulty.mixed {
    background: rgba(124, 58, 237, 0.12);
    color: #7c3aed;
    font-weight: 600;
}

.lesson-track {
    margin: 0 0 1rem;
    font-size: 0.9rem;
}

.qa-item {
    margin-bottom: 1.75rem;
    padding: 1rem 1rem 1rem 1rem;
    border-left: 3px solid var(--accent-yellow, #d29922);
    background: var(--bg-tertiary, rgba(0,0,0,0.03));
    border-radius: 0 var(--radius-md, 8px) var(--radius-md, 8px) 0;
}
.qa-q {
    margin-bottom: 0.75rem;
    line-height: 1.5;
}
.qa-a {
    color: var(--text-secondary);
    line-height: 1.6;
}
.qa-a pre {
    margin: 0.75rem 0 0;
    font-size: 0.85rem;
}

/* Interview MCQ (EmbeddedInterviewPrep bank) */
.mcq-intro {
    margin-bottom: 1.25rem;
}
.mcq-intro .lesson-lead {
    font-size: 1.05rem;
    line-height: 1.55;
    margin: 0 0 0.75rem;
    color: var(--text-secondary);
}
.mcq-meta-line {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin: 0;
}
.mcq-stack {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}
.mcq-card {
    padding: 1rem 1.1rem;
    background: var(--bg-tertiary, rgba(0, 0, 0, 0.04));
    border-radius: var(--radius-md, 8px);
    border: 1px solid var(--border-subtle, rgba(0, 0, 0, 0.08));
}
.mcq-qline {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin: 0 0 0.5rem;
}
.mcq-diff {
    display: inline-block;
    padding: 0.1rem 0.45rem;
    border-radius: 4px;
    font-size: 0.78rem;
    font-weight: 600;
    text-transform: capitalize;
}
.mcq-diff-easy {
    background: rgba(34, 197, 94, 0.15);
    color: #15803d;
}
.mcq-diff-medium {
    background: rgba(234, 179, 8, 0.2);
    color: #a16207;
}
.mcq-diff-hard {
    background: rgba(239, 68, 68, 0.15);
    color: #b91c1c;
}
.mcq-qtext {
    margin: 0 0 0.85rem;
    line-height: 1.55;
    font-size: 0.98rem;
}
.mcq-options {
    display: flex;
    flex-direction: column;
    gap: 0.45rem;
}
.mcq-option {
    text-align: left;
    padding: 0.65rem 0.85rem;
    border-radius: 8px;
    border: 1px solid var(--border-subtle, rgba(0, 0, 0, 0.12));
    background: var(--bg-primary, #fff);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.92rem;
    line-height: 1.45;
    cursor: pointer;
    transition: border-color 0.15s, background 0.15s;
}
.mcq-option:hover:not(:disabled) {
    border-color: var(--accent-blue, #2563eb);
    background: rgba(37, 99, 235, 0.06);
}
.mcq-option.is-selected:not(.is-wrong) {
    border-color: var(--accent-blue, #2563eb);
    background: rgba(37, 99, 235, 0.1);
}
.mcq-option.is-correct {
    border-color: #16a34a;
    background: rgba(22, 163, 74, 0.12);
}
.mcq-option.is-wrong {
    border-color: #dc2626;
    background: rgba(220, 38, 38, 0.1);
}
.mcq-option:disabled {
    cursor: default;
    opacity: 0.95;
}
.mcq-footer-actions {
    margin: 1.5rem 0 0;
    display: flex;
    justify-content: center;
}
.btn-mcq-submit {
    padding: 0.75rem 1.75rem;
    font-size: 1rem;
    font-weight: 600;
    font-family: inherit;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    background: linear-gradient(135deg, var(--accent-blue, #2563eb), #1d4ed8);
    color: #fff;
    box-shadow: 0 2px 8px rgba(37, 99, 235, 0.35);
}
.btn-mcq-submit:hover {
    filter: brightness(1.05);
}
.mcq-result {
    margin-top: 1.5rem;
    padding: 1.25rem 1.5rem;
    border-radius: var(--radius-md, 8px);
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.08), rgba(13, 148, 136, 0.08));
    border: 1px solid rgba(37, 99, 235, 0.25);
}
.mcq-result-title {
    margin: 0 0 0.5rem;
    font-size: 1.15rem;
}
.mcq-result-score {
    font-size: 1.75rem;
    font-weight: 700;
    margin: 0 0 0.5rem;
}
.mcq-pct {
    font-weight: 600;
    color: var(--text-secondary);
    font-size: 1.1rem;
}
.mcq-result-hint {
    margin: 0;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* Mock interview (text) - InterviewPreperationAgent question bank */
.lesson-navigation.lesson-nav-hidden {
    display: none;
}
.mock-interview-wrap {
    max-width: 720px;
}
.mock-h2 {
    margin: 0 0 0.75rem;
    font-size: 1.35rem;
}
.mock-lead {
    font-size: 1.1rem;
    margin: 0 0 1rem;
}
.mock-meta {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin: 1rem 0;
}
.mock-progress {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin: 0 0 1rem;
}
.mock-qbox {
    padding: 1rem 1.1rem;
    background: var(--bg-tertiary, rgba(0, 0, 0, 0.04));
    border-radius: var(--radius-md, 8px);
    border-left: 3px solid var(--accent-blue, #2563eb);
    margin-bottom: 1rem;
}
.mock-qtext {
    margin: 0;
    line-height: 1.55;
    font-size: 1.02rem;
}
.mock-qpreview {
    font-size: 0.88rem;
    color: var(--text-secondary);
    line-height: 1.45;
    margin: 0 0 1rem;
}
.mock-label {
    display: block;
    font-weight: 600;
    margin-bottom: 0.35rem;
    font-size: 0.95rem;
}
.mock-textarea {
    width: 100%;
    box-sizing: border-box;
    padding: 0.85rem 1rem;
    font-family: inherit;
    font-size: 0.95rem;
    line-height: 1.5;
    border-radius: 8px;
    border: 1px solid var(--border-subtle, rgba(0, 0, 0, 0.15));
    resize: vertical;
    min-height: 160px;
    margin-bottom: 1rem;
}
.mock-actions {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}
.btn-mock-primary,
.btn-mock-secondary {
    padding: 0.7rem 1.4rem;
    font-size: 1rem;
    font-weight: 600;
    font-family: inherit;
    border-radius: 10px;
    cursor: pointer;
    border: none;
}
.btn-mock-primary {
    background: linear-gradient(135deg, var(--accent-blue, #2563eb), #1d4ed8);
    color: #fff;
}
.btn-mock-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-subtle);
}
.mock-feedback-card {
    padding: 1rem 1.15rem;
    background: rgba(37, 99, 235, 0.06);
    border-radius: 8px;
    border: 1px solid rgba(37, 99, 235, 0.2);
    margin: 1rem 0;
}
.mock-scoreline {
    margin: 0 0 0.5rem;
    font-size: 1.15rem;
}
.mock-feedback-list {
    margin: 0;
    padding-left: 1.25rem;
    line-height: 1.55;
    color: var(--text-secondary);
}
.mock-score-table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
    font-size: 0.95rem;
}
.mock-score-table th,
.mock-score-table td {
    border: 1px solid var(--border-subtle);
    padding: 0.5rem 0.75rem;
    text-align: left;
}
.mock-score-table th {
    background: var(--bg-tertiary);
}

.duration {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
}

.card-progress {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.progress-bar {
    flex: 1;
    height: 6px;
    background: var(--bg-tertiary);
    border-radius: 3px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-green), var(--accent-cyan));
    border-radius: 3px;
    transition: width var(--transition-slow);
}

.progress-text {
    font-size: 0.75rem;
    color: var(--text-muted);
    white-space: nowrap;
}

/* ============================================
   Lesson View
   ============================================ */
.lesson-container {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: var(--space-xl);
    min-height: calc(100vh - 200px);
}

/* Sidebar */
.lesson-sidebar {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    position: sticky;
    top: 100px;
    height: fit-content;
    max-height: calc(100vh - 140px);
    overflow-y: auto;
}

.back-btn {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-sm) var(--space-md);
    background: transparent;
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    font-family: var(--font-primary);
    font-size: 0.85rem;
    cursor: pointer;
    transition: all var(--transition-fast);
    margin-bottom: var(--space-lg);
    width: 100%;
}

.back-btn svg {
    width: 16px;
    height: 16px;
}

.back-btn:hover {
    color: var(--text-primary);
    border-color: var(--accent-green-dim);
    background: var(--bg-hover);
}

.sidebar-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--accent-green);
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-md);
    border-bottom: 1px solid var(--border-primary);
}

.steps-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.step-item {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-sm) var(--space-md);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.step-item:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.step-item.active {
    background: rgba(63, 185, 80, 0.15);
    color: var(--accent-green);
}

.step-item.completed {
    color: var(--text-muted);
}

.step-item.completed::before {
    content: '✓';
    color: var(--accent-green);
    font-weight: bold;
}

.step-number {
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-tertiary);
    border-radius: 50%;
    font-size: 0.75rem;
    font-weight: 600;
    flex-shrink: 0;
}

.step-item.active .step-number {
    background: var(--accent-green);
    color: var(--bg-primary);
}

.step-item.completed .step-number {
    background: var(--accent-green-dim);
    color: var(--text-primary);
}

/* Lesson Content */
.lesson-content {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-lg);
    padding: var(--space-xl);
}

.lesson-header {
    margin-bottom: var(--space-xl);
    padding-bottom: var(--space-lg);
    border-bottom: 1px solid var(--border-primary);
}

.step-indicator {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: var(--space-sm);
}

.step-separator {
    color: var(--text-muted);
}

.lesson-title {
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--text-primary);
}

.lesson-body {
    font-size: 1rem;
    line-height: 1.8;
    color: var(--text-secondary);
}

.lesson-body h2 {
    font-size: 1.35rem;
    color: var(--text-primary);
    margin: var(--space-xl) 0 var(--space-md);
    padding-bottom: var(--space-sm);
    border-bottom: 1px solid var(--border-primary);
}

.lesson-body h3 {
    font-size: 1.1rem;
    color: var(--accent-cyan);
    margin: var(--space-lg) 0 var(--space-md);
}

.lesson-body p {
    margin-bottom: var(--space-md);
}

.lesson-body ul, .lesson-body ol {
    margin: var(--space-md) 0;
    padding-left: var(--space-lg);
}

.lesson-body li {
    margin-bottom: var(--space-sm);
}

.lesson-body strong {
    color: var(--text-primary);
    font-weight: 600;
}

.lesson-body em {
    color: var(--accent-yellow);
    font-style: normal;
}

/* Code Blocks */
.code-block {
    background: var(--bg-primary);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    margin: var(--space-lg) 0;
    overflow: hidden;
}

.code-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-sm) var(--space-md);
    background: var(--bg-tertiary);
    border-bottom: 1px solid var(--border-primary);
}

.code-filename {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.copy-btn {
    padding: var(--space-xs) var(--space-sm);
    background: transparent;
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-sm);
    color: var(--text-muted);
    font-size: 0.75rem;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.copy-btn:hover {
    color: var(--text-primary);
    border-color: var(--accent-green);
}

.code-content {
    padding: var(--space-md);
    overflow-x: auto;
}

.code-content pre {
    margin: 0;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    line-height: 1.6;
}

.code-content code {
    font-family: var(--font-mono);
}

/* Syntax Highlighting */
.keyword { color: var(--syntax-keyword); }
.string { color: var(--syntax-string); }
.function { color: var(--syntax-function); }
.comment { color: var(--syntax-comment); font-style: italic; }
.number { color: var(--syntax-number); }
.type { color: var(--syntax-type); }
.preprocessor { color: var(--accent-orange); }

/* Info/Tip/Warning Boxes */
.info-box {
    padding: var(--space-md) var(--space-lg);
    border-radius: var(--radius-md);
    margin: var(--space-lg) 0;
    border-left: 4px solid;
}

.info-box.tip {
    background: rgba(63, 185, 80, 0.1);
    border-color: var(--accent-green);
}

.info-box.note {
    background: rgba(88, 166, 255, 0.1);
    border-color: var(--accent-blue);
}

.info-box.warning {
    background: rgba(210, 153, 34, 0.1);
    border-color: var(--accent-yellow);
}

.info-box.important {
    background: rgba(248, 81, 73, 0.1);
    border-color: var(--accent-red);
}

.info-box-title {
    font-weight: 600;
    margin-bottom: var(--space-sm);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.info-box.tip .info-box-title { color: var(--accent-green); }
.info-box.note .info-box-title { color: var(--accent-blue); }
.info-box.warning .info-box-title { color: var(--accent-yellow); }
.info-box.important .info-box-title { color: var(--accent-red); }

/* Tables */
.lesson-table {
    width: 100%;
    border-collapse: collapse;
    margin: var(--space-lg) 0;
    font-size: 0.9rem;
}

.lesson-table th,
.lesson-table td {
    padding: var(--space-sm) var(--space-md);
    text-align: left;
    border: 1px solid var(--border-primary);
}

.lesson-table th {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    font-weight: 600;
}

.lesson-table tr:nth-child(even) {
    background: var(--bg-secondary);
}

.lesson-table code {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    background: var(--bg-primary);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    color: var(--accent-cyan);
}

/* Lesson Navigation */
.lesson-navigation {
    display: flex;
    justify-content: space-between;
    margin-top: var(--space-2xl);
    padding-top: var(--space-lg);
    border-top: 1px solid var(--border-primary);
}

.nav-button {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-md) var(--space-lg);
    background: var(--bg-tertiary);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: var(--font-primary);
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.nav-button svg {
    width: 18px;
    height: 18px;
}

.nav-button:hover:not(:disabled) {
    border-color: var(--accent-green);
    background: var(--bg-hover);
}

.nav-button:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.nav-button.next {
    background: var(--accent-green-dim);
    border-color: var(--accent-green);
}

.nav-button.next:hover:not(:disabled) {
    background: var(--accent-green);
    color: var(--bg-primary);
}

/* ============================================
   Progress View
   ============================================ */
.progress-container {
    max-width: 900px;
    margin: 0 auto;
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: var(--space-xl);
    text-align: center;
}

.progress-overview {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-lg);
    margin-bottom: var(--space-2xl);
}

.overview-card {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-lg);
    padding: var(--space-xl);
    text-align: center;
}

.overview-value {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--accent-green);
    margin-bottom: var(--space-sm);
}

.overview-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.driver-progress-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.driver-progress-item {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    padding: var(--space-lg);
    display: flex;
    align-items: center;
    gap: var(--space-lg);
}

.driver-progress-icon {
    width: 48px;
    height: 48px;
    padding: var(--space-sm);
    border-radius: var(--radius-md);
}

.driver-progress-info {
    flex: 1;
}

.driver-progress-name {
    font-weight: 600;
    margin-bottom: var(--space-sm);
}

.driver-progress-bar {
    height: 8px;
    background: var(--bg-tertiary);
    border-radius: 4px;
    overflow: hidden;
}

.driver-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-green), var(--accent-cyan));
    border-radius: 4px;
    transition: width var(--transition-slow);
}

.driver-progress-percent {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--accent-green);
    min-width: 60px;
    text-align: right;
}

/* ============================================
   Reference View
   ============================================ */
.reference-container {
    max-width: 1000px;
    margin: 0 auto;
}

.reference-tabs {
    display: flex;
    gap: var(--space-sm);
    margin-bottom: var(--space-xl);
    border-bottom: 1px solid var(--border-primary);
    padding-bottom: var(--space-md);
}

.ref-tab {
    padding: var(--space-sm) var(--space-lg);
    background: transparent;
    border: none;
    border-radius: var(--radius-md) var(--radius-md) 0 0;
    color: var(--text-secondary);
    font-family: var(--font-primary);
    font-size: 0.95rem;
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
}

.ref-tab::after {
    content: '';
    position: absolute;
    bottom: calc(-1 * var(--space-md) - 1px);
    left: 0;
    right: 0;
    height: 2px;
    background: var(--accent-green);
    transform: scaleX(0);
    transition: transform var(--transition-fast);
}

.ref-tab:hover {
    color: var(--text-primary);
}

.ref-tab.active {
    color: var(--accent-green);
}

.ref-tab.active::after {
    transform: scaleX(1);
}

.reference-content {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-lg);
    padding: var(--space-xl);
}

/* ============================================
   Footer
   ============================================ */
.footer {
    text-align: center;
    padding: var(--space-xl);
    border-top: 1px solid var(--border-primary);
    color: var(--text-muted);
    font-size: 0.85rem;
}

.footer-note {
    margin-top: var(--space-sm);
    color: var(--text-muted);
    opacity: 0.7;
}

.footer-developer {
    margin-top: var(--space-lg);
    padding-top: var(--space-md);
    border-top: 1px solid var(--border-primary);
}

.footer-developer p {
    margin-bottom: var(--space-sm);
}

.footer-developer strong {
    color: var(--accent-green);
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: var(--space-lg);
    margin-top: var(--space-sm);
}

.footer-link {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.85rem;
    padding: var(--space-xs) var(--space-sm);
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.footer-link:hover {
    color: var(--accent-green);
    background: rgba(63, 185, 80, 0.1);
}

.footer-link svg {
    flex-shrink: 0;
}

.footer-link.coffee-link {
    color: #ffdd00;
    border: 1px solid rgba(255, 221, 0, 0.3);
    background: rgba(255, 221, 0, 0.1);
}

.footer-link.coffee-link:hover {
    color: #ffdd00;
    background: rgba(255, 221, 0, 0.2);
    border-color: #ffdd00;
    box-shadow: 0 0 15px rgba(255, 221, 0, 0.3);
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 1024px) {
    .lesson-container {
        grid-template-columns: 1fr;
    }
    
    .lesson-sidebar {
        position: static;
        max-height: none;
    }
}

@media (max-width: 768px) {
    .header {
        flex-direction: column;
        gap: var(--space-md);
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .driver-grid {
        grid-template-columns: 1fr;
    }
    
    .progress-overview {
        grid-template-columns: 1fr;
    }
    
    .main-content {
        padding: var(--space-md);
    }
}

/* ============================================
   Animations
   ============================================ */
@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.driver-card {
    animation: slideIn 0.4s ease forwards;
}

.driver-card:nth-child(1) { animation-delay: 0.05s; }
.driver-card:nth-child(2) { animation-delay: 0.1s; }
.driver-card:nth-child(3) { animation-delay: 0.15s; }
.driver-card:nth-child(4) { animation-delay: 0.2s; }
.driver-card:nth-child(5) { animation-delay: 0.25s; }
.driver-card:nth-child(6) { animation-delay: 0.3s; }

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--border-primary);
    border-radius: 4px;
}

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

/* ============================================
   Celebration & Fireworks
   ============================================ */
.celebration-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(10, 14, 20, 0.95);
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.5s ease;
}

.celebration-overlay.active {
    opacity: 1;
    visibility: visible;
}

.fireworks-container {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    pointer-events: none;
    overflow: hidden;
}

.firework {
    position: absolute;
    width: 4px;
    height: 4px;
}

.particle {
    position: absolute;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    animation: explode 1.5s ease-out forwards;
}

@keyframes explode {
    0% {
        transform: translate(0, 0) scale(1);
        opacity: 1;
    }
    100% {
        transform: translate(
            calc(cos(var(--angle)) * var(--velocity)),
            calc(sin(var(--angle)) * var(--velocity))
        ) scale(0);
        opacity: 0;
    }
}

/* Fallback for browsers that don't support trigonometric functions */
@supports not (transform: translate(calc(cos(45deg) * 50px), 0)) {
    .particle:nth-child(1) { animation: particle1 1.5s ease-out forwards; }
    .particle:nth-child(2) { animation: particle2 1.5s ease-out forwards; }
    .particle:nth-child(3) { animation: particle3 1.5s ease-out forwards; }
    .particle:nth-child(4) { animation: particle4 1.5s ease-out forwards; }
    .particle:nth-child(5) { animation: particle5 1.5s ease-out forwards; }
    .particle:nth-child(6) { animation: particle6 1.5s ease-out forwards; }
    .particle:nth-child(7) { animation: particle7 1.5s ease-out forwards; }
    .particle:nth-child(8) { animation: particle8 1.5s ease-out forwards; }
    .particle:nth-child(9) { animation: particle9 1.5s ease-out forwards; }
    .particle:nth-child(10) { animation: particle10 1.5s ease-out forwards; }
    .particle:nth-child(11) { animation: particle11 1.5s ease-out forwards; }
    .particle:nth-child(12) { animation: particle12 1.5s ease-out forwards; }
}

@keyframes particle1 { 0% { transform: translate(0,0) scale(1); opacity:1; } 100% { transform: translate(80px, 0) scale(0); opacity:0; } }
@keyframes particle2 { 0% { transform: translate(0,0) scale(1); opacity:1; } 100% { transform: translate(56px, 56px) scale(0); opacity:0; } }
@keyframes particle3 { 0% { transform: translate(0,0) scale(1); opacity:1; } 100% { transform: translate(0, 80px) scale(0); opacity:0; } }
@keyframes particle4 { 0% { transform: translate(0,0) scale(1); opacity:1; } 100% { transform: translate(-56px, 56px) scale(0); opacity:0; } }
@keyframes particle5 { 0% { transform: translate(0,0) scale(1); opacity:1; } 100% { transform: translate(-80px, 0) scale(0); opacity:0; } }
@keyframes particle6 { 0% { transform: translate(0,0) scale(1); opacity:1; } 100% { transform: translate(-56px, -56px) scale(0); opacity:0; } }
@keyframes particle7 { 0% { transform: translate(0,0) scale(1); opacity:1; } 100% { transform: translate(0, -80px) scale(0); opacity:0; } }
@keyframes particle8 { 0% { transform: translate(0,0) scale(1); opacity:1; } 100% { transform: translate(56px, -56px) scale(0); opacity:0; } }
@keyframes particle9 { 0% { transform: translate(0,0) scale(1); opacity:1; } 100% { transform: translate(70px, 30px) scale(0); opacity:0; } }
@keyframes particle10 { 0% { transform: translate(0,0) scale(1); opacity:1; } 100% { transform: translate(-70px, 30px) scale(0); opacity:0; } }
@keyframes particle11 { 0% { transform: translate(0,0) scale(1); opacity:1; } 100% { transform: translate(30px, -70px) scale(0); opacity:0; } }
@keyframes particle12 { 0% { transform: translate(0,0) scale(1); opacity:1; } 100% { transform: translate(-30px, -70px) scale(0); opacity:0; } }

.celebration-content {
    position: relative;
    z-index: 10;
    text-align: center;
    max-width: 500px;
    padding: var(--space-2xl);
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-xl);
    box-shadow: 0 25px 80px rgba(0, 0, 0, 0.5), 0 0 100px rgba(63, 185, 80, 0.2);
    transform: scale(0.8) translateY(20px);
    opacity: 0;
    transition: all 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.celebration-overlay.active .celebration-content {
    transform: scale(1) translateY(0);
    opacity: 1;
    transition-delay: 0.2s;
}

.trophy-icon {
    font-size: 5rem;
    margin-bottom: var(--space-md);
    animation: bounce 1s ease infinite;
    filter: drop-shadow(0 0 20px rgba(255, 215, 0, 0.5));
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
}

.celebration-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--space-sm);
    background: linear-gradient(135deg, var(--accent-green), var(--accent-cyan), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: shimmer 3s ease infinite;
    background-size: 200% 200%;
}

@keyframes shimmer {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.celebration-subtitle {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-lg);
}

.driver-name {
    color: var(--accent-green);
    font-weight: 600;
}

.achievement-badge {
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    padding: var(--space-md) var(--space-xl);
    background: linear-gradient(135deg, rgba(63, 185, 80, 0.2), rgba(57, 197, 207, 0.2));
    border: 2px solid var(--accent-green);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-lg);
    animation: glow 2s ease-in-out infinite alternate;
}

@keyframes glow {
    from { box-shadow: 0 0 10px rgba(63, 185, 80, 0.3), 0 0 20px rgba(63, 185, 80, 0.2); }
    to { box-shadow: 0 0 20px rgba(63, 185, 80, 0.5), 0 0 40px rgba(63, 185, 80, 0.3); }
}

.badge-icon {
    font-size: 2rem;
    margin-bottom: var(--space-xs);
    animation: spin 3s linear infinite;
}

@keyframes spin {
    0% { transform: rotateY(0deg); }
    100% { transform: rotateY(360deg); }
}

.badge-text {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 2px;
}

.badge-name {
    font-size: 1rem;
    font-weight: 600;
    color: var(--accent-green);
    margin-top: var(--space-xs);
}

.celebration-message {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-xl);
    line-height: 1.6;
}

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

.celebration-btn {
    padding: var(--space-md) var(--space-xl);
    border-radius: var(--radius-md);
    font-family: var(--font-primary);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: none;
}

.celebration-btn.secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-primary);
}

.celebration-btn.secondary:hover {
    background: var(--bg-hover);
    border-color: var(--accent-green);
}

.celebration-btn.primary {
    background: linear-gradient(135deg, var(--accent-green), var(--accent-cyan));
    color: var(--bg-primary);
}

.celebration-btn.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(63, 185, 80, 0.4);
}

/* Confetti burst animation for extra particles */
.celebration-overlay.active::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 200px;
    height: 200px;
    transform: translate(-50%, -50%);
    background: radial-gradient(circle, rgba(63, 185, 80, 0.3) 0%, transparent 70%);
    animation: burst 1s ease-out forwards;
}

@keyframes burst {
    0% { transform: translate(-50%, -50%) scale(0); opacity: 1; }
    100% { transform: translate(-50%, -50%) scale(5); opacity: 0; }
}