:root {
    /* Dark Sophisticated Color Scheme */
    --deep-space: #0a0a0a;
    --midnight: #1a1a1a;
    --charcoal: #2d2d2d;
    --steel: #3a3a3a;
    --silver: #e8e8e8;
    --platinum: #f8f8f8;
    --neon-blue: #00d4ff;
    --electric-purple: #8a2be2;
    --cyber-green: #00ff88;
    --matrix-green: #00ff41;
    --hologram-teal: #20c997;
    --warning-gold: #ffd700;
    --danger-neon: #ff073a;
}

[data-theme="light"] {
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #e9ecef;
    --text-primary: #1a1a1a;
    --text-secondary: #4a4a4a;
    --text-muted: #6c757d;
    --border: #dee2e6;
    --accent-primary: #00b04f;
    --accent-secondary: #008c3a;
}

[data-theme="dark"] {
    --bg-primary: #0a0a0a;
    --bg-secondary: #1a1a1a;
    --bg-tertiary: #2d2d2d;
    --text-primary: #e8e8e8;
    --text-secondary: #b0b0b0;
    --text-muted: #888888;
    --border: #3a3a3a;
    --accent-primary: #00ff88;
    --accent-secondary: #00d4ff;
}

/* Apply theme variables */
body {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: background-color 0.3s ease, color 0.3s ease;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 0;
}

.container {
    max-width: 75%;
    margin: 0 auto;
    padding: 0 20px;
}

.full-width {
    width: 100%;
}

/* Enhanced Theme Toggle Button */
.theme-toggle {
    background: var(--bg-secondary);
    border: 2px solid var(--border);
    color: var(--text-primary);
    cursor: pointer;
    font-size: 1.2rem;
    padding: 10px;
    border-radius: 50%;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    margin-left: 10px;
    position: relative;
    overflow: hidden;
}

.theme-toggle::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.1), transparent);
    transition: left 0.5s;
}

.theme-toggle:hover::before {
    left: 100%;
}

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

.theme-toggle .fa-sun {
    display: none;
    color: #ffd700;
}

.theme-toggle .fa-moon {
    color: var(--accent-secondary);
}

[data-theme="dark"] .theme-toggle .fa-moon {
    display: none;
}

[data-theme="dark"] .theme-toggle .fa-sun {
    display: block;
}

/* Header Styles */
header {
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border);
    padding: 15px 0;
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.8rem;
    font-weight: 700;
    text-decoration: none;
    color: var(--accent-primary);
}

.logo span {
    color: var(--text-primary);
}

.nav-menu {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
    gap: 25px;
}

.nav-menu a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
}

.nav-menu a:hover, .nav-menu a.active {
    color: var(--accent-primary);
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 15px;
}

.auth-buttons a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
}

.mobile-toggle {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
}

/* Fixed Crypto Ticker */
.crypto-ticker {
    background: var(--bg-tertiary);
    border-bottom: 1px solid var(--border);
    padding: 10px 0;
    overflow: hidden;
    position: relative;
}

.ticker-container {
    white-space: nowrap;
    animation: ticker 30s linear infinite;
    color: var(--text-primary);
    font-weight: 600;
    font-size: 0.9rem;
    padding: 5px 0;
}

.crypto-ticker::before,
.crypto-ticker::after {
    content: '';
    position: absolute;
    top: 0;
    bottom: 0;
    width: 50px;
    z-index: 2;
    pointer-events: none;
}

.crypto-ticker::before {
    left: 0;
    background: linear-gradient(to right, var(--bg-tertiary), transparent);
}

.crypto-ticker::after {
    right: 0;
    background: linear-gradient(to left, var(--bg-tertiary), transparent);
}

@keyframes ticker {
    0% { transform: translateX(100%); }
    100% { transform: translateX(-100%); }
}

.ticker-item {
    display: inline-block;
    margin: 0 15px;
}

.ticker-separator {
    color: var(--text-muted);
    margin: 0 10px;
}

.change.positive {
    color: var(--accent-primary);
}

.change.negative {
    color: var(--danger-neon);
}

/* CryptoPulse Style Learning Platform */
.learning-platform {
    background: linear-gradient(135deg, var(--deep-space) 0%, var(--charcoal) 50%, var(--midnight) 100%);
    color: var(--text-primary);
    padding: 80px 0;
    position: relative;
    overflow: hidden;
    border-bottom: 1px solid var(--border);
}

.learning-platform::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(circle at 20% 80%, rgba(0, 212, 255, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(138, 43, 226, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 40% 40%, rgba(0, 255, 136, 0.05) 0%, transparent 50%);
    pointer-events: none;
}

.platform-header {
    text-align: center;
    max-width: 800px;
    margin: 0 auto 50px;
    position: relative;
}

.platform-header h1 {
    font-size: 3.5rem;
    margin-bottom: 20px;
    font-weight: 700;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 0 30px rgba(0, 255, 136, 0.3);
}

.platform-header p {
    font-size: 1.3rem;
    color: var(--text-secondary);
    line-height: 1.6;
    font-weight: 300;
}

.progress-indicator {
    background: rgba(255,255,255,0.05);
    padding: 25px;
    border-radius: 15px;
    backdrop-filter: blur(10px);
    border: 1px solid var(--border);
    max-width: 600px;
    margin: 0 auto 40px;
    position: relative;
    overflow: hidden;
}

.progress-indicator::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
}

.progress-stats {
    display: flex;
    justify-content: space-between;
    margin-bottom: 15px;
    font-size: 1.1rem;
    color: var(--text-secondary);
}

.progress-bar {
    background: var(--bg-tertiary);
    height: 8px;
    border-radius: 10px;
    overflow: hidden;
    position: relative;
}

.progress-fill {
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    height: 100%;
    border-radius: 10px;
    width: 25%;
    transition: width 0.3s ease;
    position: relative;
}

.progress-fill::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    animation: shimmer 2s infinite;
}

@keyframes shimmer {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

/* Fixed Course Navigation */
.course-nav {
    background: var(--bg-secondary);
    padding: 0;
    border-radius: 15px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.3);
    margin-bottom: 40px;
    border: 1px solid var(--border);
    position: relative;
}

.course-tabs {
    display: flex;
    overflow-x: auto;
    padding: 0;
    margin: 0;
    list-style: none;
    border-bottom: 1px solid var(--border);
    background: var(--bg-secondary);
}

.course-tab {
    padding: 20px 30px;
    cursor: pointer;
    border-bottom: 3px solid transparent;
    transition: all 0.3s ease;
    white-space: nowrap;
    font-weight: 600;
    color: var(--text-secondary);
    position: relative;
    background: transparent;
}

.course-tab::before {
    content: '';
    position: absolute;
    bottom: -3px;
    left: 50%;
    width: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    transition: all 0.3s ease;
    transform: translateX(-50%);
}

.course-tab.active {
    color: var(--accent-primary);
    background: rgba(0, 255, 136, 0.05);
}

.course-tab.active::before {
    width: 100%;
}

.course-tab:hover {
    color: var(--accent-primary);
    background: rgba(0, 255, 136, 0.02);
}

.course-tab:hover::before {
    width: 80%;
}

/* Chapter System */
.chapter-system {
    background: var(--bg-secondary);
    border-radius: 15px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.3);
    overflow: hidden;
    border: 1px solid var(--border);
    display: flex;
    min-height: 600px;
}

.chapter-sidebar {
    background: var(--bg-tertiary);
    padding: 30px;
    border-right: 1px solid var(--border);
    min-height: 600px;
    flex: 0 0 300px;
}

.chapter-sidebar h3 {
    color: var(--accent-primary);
    margin-bottom: 25px;
    font-size: 1.3rem;
    font-weight: 600;
    border-bottom: 2px solid var(--border);
    padding-bottom: 10px;
}

.chapter-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.chapter-item {
    padding: 15px 20px;
    margin-bottom: 10px;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.3s ease;
    border-left: 4px solid transparent;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    position: relative;
    overflow: hidden;
}

.chapter-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(0, 255, 136, 0.1), transparent);
    transition: left 0.5s;
}

.chapter-item:hover::before {
    left: 100%;
}

.chapter-item.active {
    background: rgba(0, 255, 136, 0.1);
    border-left-color: var(--accent-primary);
    box-shadow: 0 4px 15px rgba(0, 255, 136, 0.2);
    color: var(--text-primary);
    transform: translateX(5px);
}

.chapter-item.completed {
    background: rgba(0, 212, 255, 0.1);
    border-left-color: var(--accent-secondary);
    color: var(--text-primary);
}

.chapter-item:hover {
    background: rgba(0, 255, 136, 0.05);
    transform: translateX(5px);
    color: var(--text-primary);
}

.chapter-number {
    display: inline-block;
    width: 30px;
    height: 30px;
    background: var(--bg-tertiary);
    border-radius: 50%;
    text-align: center;
    line-height: 30px;
    margin-right: 15px;
    font-weight: 600;
    color: var(--text-secondary);
    transition: all 0.3s ease;
}

.chapter-item.active .chapter-number {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: var(--deep-space);
    box-shadow: 0 0 15px rgba(0, 255, 136, 0.5);
}

.chapter-item.completed .chapter-number {
    background: var(--accent-secondary);
    color: var(--deep-space);
}

.chapter-content {
    padding: 40px;
    min-height: 600px;
    flex: 1;
    background: var(--bg-secondary);
}

.chapter-header {
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 2px solid var(--border);
}

.chapter-header h2 {
    font-size: 2.5rem;
    color: var(--accent-primary);
    margin-bottom: 10px;
    font-weight: 700;
}

.chapter-meta {
    display: flex;
    gap: 20px;
    color: var(--text-muted);
    font-size: 0.9rem;
}

.chapter-body {
    line-height: 1.8;
    color: var(--text-primary);
}

.chapter-body h3 {
    font-size: 1.8rem;
    margin: 30px 0 15px;
    color: var(--accent-secondary);
    font-weight: 600;
}

.chapter-body p {
    font-size: 1.1rem;
    margin-bottom: 20px;
    color: var(--text-primary);
}

.concept-box {
    background: rgba(0, 255, 136, 0.05);
    padding: 25px;
    border-radius: 10px;
    border-left: 4px solid var(--accent-primary);
    margin: 25px 0;
    border: 1px solid rgba(0, 255, 136, 0.2);
}

.concept-box h4 {
    color: var(--accent-primary);
    margin-bottom: 10px;
    font-size: 1.3rem;
    font-weight: 600;
}

.image-explanation {
    text-align: center;
    margin: 30px 0;
}

.image-explanation img {
    max-width: 100%;
    border-radius: 10px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.3);
    margin-bottom: 15px;
    border: 1px solid var(--border);
}

.image-caption {
    color: var(--text-muted);
    font-style: italic;
    font-size: 0.9rem;
}

.key-points {
    background: rgba(0, 212, 255, 0.05);
    padding: 25px;
    border-radius: 10px;
    margin: 25px 0;
    border: 1px solid rgba(0, 212, 255, 0.2);
}

.key-points h4 {
    color: var(--accent-secondary);
    margin-bottom: 15px;
    font-weight: 600;
}

.key-points ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.key-points li {
    padding: 8px 0;
    display: flex;
    align-items: center;
    color: var(--text-primary);
}

.key-points li::before {
    content: '✓';
    color: var(--accent-secondary);
    font-weight: bold;
    margin-right: 10px;
    font-size: 1.1rem;
}

.chapter-navigation {
    display: flex;
    justify-content: space-between;
    margin-top: 40px;
    padding-top: 20px;
    border-top: 1px solid var(--border);
}

/* Enhanced Buttons */
.btn {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border);
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
    position: relative;
    overflow: hidden;
    font-family: inherit;
    font-size: 1rem;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.1), transparent);
    transition: left 0.5s;
}

.btn:hover::before {
    left: 100%;
}

.btn:hover {
    background: var(--bg-secondary);
    border-color: var(--accent-primary);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 255, 136, 0.3);
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: var(--deep-space);
    border: none;
    font-weight: 700;
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--accent-secondary), var(--accent-primary));
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 255, 136, 0.4);
}

/* Enhanced Quiz System with Multiple Questions */
.quiz-section {
    margin: 40px 0;
    padding: 30px;
    background: var(--bg-tertiary);
    border-radius: 15px;
    border: 1px solid var(--border);
}

.quiz-header {
    margin-bottom: 25px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.quiz-progress {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--accent-primary);
}

.quiz-score {
    background: var(--bg-secondary);
    padding: 8px 16px;
    border-radius: 20px;
    font-weight: 600;
    color: var(--text-primary);
    border: 1px solid var(--border);
}

.quiz-container {
    background: var(--bg-secondary);
    padding: 25px;
    border-radius: 12px;
    border: 1px solid var(--border);
}

.quiz-question {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 25px;
    color: var(--accent-primary);
    line-height: 1.5;
}

.quiz-options {
    display: grid;
    gap: 12px;
    margin-bottom: 25px;
}

.quiz-option {
    padding: 16px 20px;
    background: var(--bg-tertiary);
    border: 2px solid var(--border);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    color: var(--text-primary);
    position: relative;
    overflow: hidden;
    font-size: 1rem;
}

.quiz-option::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(0, 255, 136, 0.1), transparent);
    transition: left 0.5s;
}

.quiz-option:hover::before {
    left: 100%;
}

.quiz-option:hover {
    border-color: var(--accent-primary);
    background: rgba(0, 255, 136, 0.05);
    transform: translateX(5px);
}

.quiz-option.selected {
    border-color: var(--accent-primary);
    background: rgba(0, 255, 136, 0.1);
    box-shadow: 0 0 15px rgba(0, 255, 136, 0.2);
}

.quiz-option.correct {
    border-color: var(--accent-primary);
    background: rgba(0, 255, 136, 0.2);
}

.quiz-option.incorrect {
    border-color: var(--danger-neon);
    background: rgba(255, 7, 58, 0.2);
}

.quiz-feedback {
    padding: 20px;
    border-radius: 8px;
    margin-top: 20px;
    font-weight: 600;
    line-height: 1.5;
    display: none;
}

.quiz-feedback.correct {
    background: rgba(0, 255, 136, 0.1);
    border: 1px solid var(--accent-primary);
    color: var(--accent-primary);
}

.quiz-feedback.incorrect {
    background: rgba(255, 7, 58, 0.1);
    border: 1px solid var(--danger-neon);
    color: var(--danger-neon);
}

.quiz-results {
    text-align: center;
    padding: 30px;
}

.quiz-results h4 {
    color: var(--accent-primary);
    margin-bottom: 15px;
    font-size: 1.5rem;
}

.quiz-score-display {
    font-size: 2rem;
    font-weight: 700;
    margin: 20px 0;
    color: var(--accent-secondary);
}

.quiz-navigation {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 25px;
    gap: 15px;
}

.quiz-navigation .btn {
    min-width: 140px;
}

.btn.disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none !important;
}

.btn.disabled:hover {
    transform: none !important;
    box-shadow: none !important;
}

/* Multiple choice question indicators */
.question-indicators {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.question-indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--bg-tertiary);
    border: 2px solid var(--border);
    cursor: pointer;
    transition: all 0.3s ease;
}

.question-indicator.active {
    background: var(--accent-primary);
    border-color: var(--accent-primary);
}

.question-indicator.answered {
    background: var(--accent-secondary);
    border-color: var(--accent-secondary);
}
/* Course Categories */
.course-categories {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin: 50px 0;
}

.category-card {
    background: var(--bg-secondary);
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.3);
    transition: all 0.3s ease;
    text-align: center;
    border: 1px solid var(--border);
    position: relative;
    overflow: hidden;
}

.category-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
}

.category-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.4);
    border-color: var(--accent-primary);
}

.category-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    font-size: 1.8rem;
    color: var(--deep-space);
    box-shadow: 0 5px 15px rgba(0, 255, 136, 0.3);
}

.category-card h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: var(--accent-primary);
    font-weight: 600;
}

.category-card p {
    color: var(--text-secondary);
    margin-bottom: 20px;
    line-height: 1.6;
}

/* Progress Management */
.progress-management {
    text-align: center;
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid var(--border);
}

/* Footer Styles */
footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border);
    padding: 50px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h3, .footer-section h4 {
    color: var(--accent-primary);
    margin-bottom: 20px;
}

.footer-section p {
    color: var(--text-secondary);
    line-height: 1.6;
}

.footer-section ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section ul li a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: var(--accent-primary);
}

.social-links {
    display: flex;
    gap: 15px;
    margin-top: 20px;
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--bg-tertiary);
    border-radius: 50%;
    color: var(--text-secondary);
    transition: all 0.3s ease;
}

.social-links a:hover {
    background: var(--accent-primary);
    color: var(--deep-space);
    transform: translateY(-3px);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid var(--border);
    color: var(--text-muted);
    font-size: 0.9rem;
}

.footer-bottom a {
    color: var(--text-secondary);
    text-decoration: none;
}

.footer-bottom a:hover {
    color: var(--accent-primary);
}

/* Toast Notifications */
.toast {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border);
    box-shadow: 0 8px 32px rgba(0,0,0,0.3);
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 15px 25px;
    border-radius: 8px;
    z-index: 1000;
    transform: translateX(150%);
    transition: transform 0.3s ease;
}

.toast.show {
    transform: translateX(0);
}

/* Mobile Optimizations */
@media (max-width: 768px) {
    .platform-header h1 {
        font-size: 2.5rem;
    }
    
    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--bg-primary);
        flex-direction: column;
        padding: 20px;
        border-top: 1px solid var(--border);
        box-shadow: 0 5px 15px rgba(0,0,0,0.2);
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .mobile-toggle {
        display: block;
    }
    
    .course-tabs {
        flex-direction: column;
    }
    
    .course-tab {
        border-bottom: 1px solid var(--border);
        border-left: 3px solid transparent;
        padding: 15px 20px;
    }
    
    .course-tab.active {
        border-left-color: var(--accent-primary);
        border-bottom-color: var(--border);
    }
    
    .course-tab::before {
        display: none;
    }
    
    .chapter-system {
        flex-direction: column;
    }
    
    .chapter-sidebar {
        border-right: none;
        border-bottom: 1px solid var(--border);
        flex: none;
        min-height: auto;
    }
    
    .chapter-content {
        padding: 25px;
    }
    
    .chapter-header h2 {
        font-size: 2rem;
    }
    
    .quiz-navigation {
        flex-direction: column;
        gap: 10px;
    }
    
    .quiz-navigation .btn {
        width: 100%;
        min-width: auto;
    }
    
    .quiz-option {
        padding: 18px 15px;
        font-size: 1.1rem;
    }
    
    .progress-indicator {
        padding: 20px;
        margin: 0 auto 30px;
    }
}

/* Touch optimizations for mobile */
@media (hover: none) {
    .quiz-option:hover {
        transform: none;
        border-color: var(--border);
    }
    
    .quiz-option:active {
        border-color: var(--accent-primary);
        background: rgba(0, 255, 136, 0.1);
    }
    
    .btn:hover {
        transform: none;
    }
    
    .btn:active {
        transform: scale(0.98);
    }
}
/* Enhanced Features Section */
.features-section {
    background: var(--bg-secondary);
    padding: 80px 0;
    border-top: 1px solid var(--border);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 20px;
    color: var(--accent-primary);
    font-weight: 700;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-top: 50px;
}

.feature-item {
    background: var(--bg-tertiary);
    padding: 30px;
    border-radius: 15px;
    text-align: center;
    border: 1px solid var(--border);
    transition: all 0.3s ease;
}

.feature-item:hover {
    transform: translateY(-5px);
    border-color: var(--accent-primary);
    box-shadow: 0 10px 30px rgba(0, 255, 136, 0.1);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 20px;
}

.feature-item h3 {
    color: var(--accent-primary);
    margin-bottom: 15px;
    font-size: 1.3rem;
}

.feature-item p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Progress Management */
.progress-management {
    text-align: center;
    margin-top: 40px;
    padding-top: 30px;
    border-top: 1px solid var(--border);
}

.progress-note {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-top: 10px;
}

/* Enhanced Quiz Styles */
.quiz-score {
    background: var(--bg-secondary);
    padding: 8px 16px;
    border-radius: 20px;
    font-weight: 600;
    color: var(--text-primary);
    border: 1px solid var(--border);
}

.question-indicators {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
    flex-wrap: wrap;
    justify-content: center;
}

.question-indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--bg-tertiary);
    border: 2px solid var(--border);
    cursor: pointer;
    transition: all 0.3s ease;
}

.question-indicator.active {
    background: var(--accent-primary);
    border-color: var(--accent-primary);
}

.question-indicator.answered {
    background: var(--accent-secondary);
    border-color: var(--accent-secondary);
}

.quiz-results {
    text-align: center;
    padding: 30px;
}

.quiz-score-display {
    font-size: 2rem;
    font-weight: 700;
    margin: 20px 0;
    color: var(--accent-secondary);
}

/* Difficulty Navigation */
.difficulty-nav {
    display: flex;
    gap: 10px;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.difficulty-btn {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 12px 24px;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 600;
}

.difficulty-btn.active {
    background: var(--accent-primary);
    color: var(--deep-space);
    border-color: var(--accent-primary);
}

.difficulty-btn:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

/* Welcome Message */
.welcome-message {
    text-align: center;
    padding: 40px;
    background: var(--bg-tertiary);
    border-radius: 15px;
    border: 1px solid var(--border);
}

.welcome-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.feature {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-secondary);
}

.feature-icon {
    font-size: 1.5rem;
}

/* Course Container */
.course-container {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 30px;
    margin-top: 30px;
}

@media (max-width: 768px) {
    .course-container {
        grid-template-columns: 1fr;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .difficulty-nav {
        justify-content: center;
    }
    
    .welcome-features {
        grid-template-columns: 1fr;
    }
}

/* Enhanced Chapter Items */
.chapter-item {
    display: flex;
    align-items: center;
    padding: 15px 20px;
    margin-bottom: 10px;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.3s ease;
    border-left: 4px solid transparent;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    position: relative;
    overflow: hidden;
}

.chapter-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(0, 255, 136, 0.1), transparent);
    transition: left 0.5s;
}

.chapter-item:hover::before {
    left: 100%;
}

.chapter-item.active {
    background: rgba(0, 255, 136, 0.1);
    border-left-color: var(--accent-primary);
    box-shadow: 0 4px 15px rgba(0, 255, 136, 0.2);
    color: var(--text-primary);
    transform: translateX(5px);
}

.chapter-item.completed {
    background: rgba(0, 212, 255, 0.1);
    border-left-color: var(--accent-secondary);
    color: var(--text-primary);
}

.chapter-item:hover {
    background: rgba(0, 255, 136, 0.05);
    transform: translateX(5px);
    color: var(--text-primary);
}

.chapter-number {
    display: inline-block;
    width: 30px;
    height: 30px;
    background: var(--bg-tertiary);
    border-radius: 50%;
    text-align: center;
    line-height: 30px;
    margin-right: 15px;
    font-weight: 600;
    color: var(--text-secondary);
    transition: all 0.3s ease;
}

.chapter-item.active .chapter-number {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: var(--deep-space);
    box-shadow: 0 0 15px rgba(0, 255, 136, 0.5);
}

.chapter-item.completed .chapter-number {
    background: var(--accent-secondary);
    color: var(--deep-space);
}
/* Crypto Ticker Styles */
.crypto-ticker {
    background: linear-gradient(135deg, #1a1a1a 0%, #2a2a2a 100%);
    border-bottom: 1px solid #333;
    padding: 8px 0;
    overflow: hidden;
    position: relative;
}

.ticker-container {
    display: flex;
    gap: 30px;
    animation: ticker-scroll 60s linear infinite;
    white-space: nowrap;
}

.ticker-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 4px 12px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 6px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 0.85rem;
    font-weight: 500;
}

.coin-name {
    color: #00ff88;
    font-weight: 600;
    text-transform: uppercase;
}

.coin-price {
    color: #ffffff;
    font-weight: 500;
}

.coin-change {
    font-weight: 600;
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 0.8rem;
}

.coin-change.positive {
    background: rgba(0, 255, 136, 0.15);
    color: #00ff88;
}

.coin-change.negative {
    background: rgba(255, 59, 92, 0.15);
    color: #ff3b5c;
}

.ticker-error {
    color: #ffa500;
    text-align: center;
    font-style: italic;
}

/* Ticker animation */
@keyframes ticker-scroll {
    0% {
        transform: translateX(100%);
    }
    100% {
        transform: translateX(-100%);
    }
}

/* Pause animation on hover */
.crypto-ticker:hover .ticker-container {
    animation-play-state: paused;
}

/* Responsive design */
@media (max-width: 768px) {
    .ticker-container {
        gap: 20px;
        animation-duration: 40s;
    }
    
    .ticker-item {
        font-size: 0.75rem;
        padding: 3px 8px;
    }
}
/* Progress Management Styles */
.progress-management {
    margin-top: 3rem;
    padding: 2rem;
    background: var(--bg-secondary);
    border-radius: 15px;
    border: 1px solid var(--border-color);
    text-align: center;
}

.progress-actions {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

.progress-note {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin: 0;
    max-width: 300px;
    line-height: 1.4;
}

.btn-warning {
    background: linear-gradient(135deg, #ff6b35, #f7931a);
    border: 1px solid #ff6b35;
    color: white;
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(247, 147, 26, 0.3);
}

.btn-warning:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(247, 147, 26, 0.4);
    background: linear-gradient(135deg, #ff7b45, #ff9a3a);
}

.btn-warning:active {
    transform: translateY(0);
}

/* Responsive design */
@media (max-width: 768px) {
    .progress-management {
        margin-top: 2rem;
        padding: 1.5rem;
    }
    
    .btn-warning {
        padding: 10px 20px;
        font-size: 0.9rem;
    }
}
/* Trading Calculators Styles */
.calculators-section {
    padding: 4rem 0;
    background: var(--bg-secondary);
    margin-top: 2rem;
}

.calculators-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.calculator-card {
    background: var(--bg-primary);
    border-radius: 15px;
    padding: 2rem;
    border: 1px solid var(--border-color);
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.calculator-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    border-color: var(--accent-primary);
}

.calculator-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.calculator-icon {
    font-size: 2rem;
}

.calculator-header h3 {
    color: var(--text-primary);
    margin: 0;
    font-size: 1.3rem;
}

.input-group {
    margin-bottom: 1rem;
}

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.input-group input,
.input-group select {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 1rem;
    transition: all 0.3s ease;
}

.input-group input:focus,
.input-group select:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(0, 255, 136, 0.1);
}

.calculator-body .btn {
    width: 100%;
    margin-top: 1rem;
    margin-bottom: 1.5rem;
}

.result {
    background: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: 10px;
    border: 1px solid var(--border-color);
}

.result-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.8rem;
    padding-bottom: 0.8rem;
    border-bottom: 1px solid var(--border-color);
}

.result-item:last-child {
    margin-bottom: 0;
    padding-bottom: 0;
    border-bottom: none;
}

.result-item span {
    color: var(--text-secondary);
}

.result-item strong {
    color: var(--accent-primary);
    font-size: 1.1rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .calculators-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .calculator-card {
        padding: 1.5rem;
    }
    
    .calculator-header {
        flex-direction: column;
        text-align: center;
        gap: 0.5rem;
    }
}

/* Dark theme enhancements */
[data-theme="dark"] .calculator-card {
    background: var(--bg-primary);
    border-color: #333;
}

[data-theme="dark"] .input-group input,
[data-theme="dark"] .input-group select {
    background: var(--bg-tertiary);
    border-color: #444;
    color: var(--text-primary);
}
/* Add these to your existing CSS */
.section-subtitle {
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 3rem;
    font-size: 1.1rem;
}

.calculator-body .btn {
    width: 100%;
    margin-top: 1rem;
    margin-bottom: 1.5rem;
}

.result {
    background: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: 10px;
    border: 1px solid var(--border-color);
}

.result-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.8rem;
    padding-bottom: 0.8rem;
    border-bottom: 1px solid var(--border-color);
}

.result-item:last-child {
    margin-bottom: 0;
    padding-bottom: 0;
    border-bottom: none;
}

.result-item span {
    color: var(--text-secondary);
}

.result-item strong {
    color: var(--accent-primary);
    font-size: 1.1rem;
}