/* ================================
   CSS Variables & Base Styles
   ================================ */
:root {
    /* Colors */
    --color-bg-dark: #0a0a0f;
    --color-bg-section: #0f0f18;
    --color-bg-card: rgba(20, 20, 35, 0.7);
    --color-primary: #9b4dff;
    --color-primary-light: #b56fff;
    --color-secondary: #00d9c4;
    --color-accent: #ffd700;
    --color-text: #e8e8f0;
    --color-text-muted: #a0a0b8;
    --color-white: #ffffff;
    --color-error: #ff4d6d;
    --color-success: #00d26a;
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, var(--color-primary) 0%, #6d28d9 100%);
    --gradient-secondary: linear-gradient(135deg, var(--color-secondary) 0%, #0891b2 100%);
    --gradient-glow: linear-gradient(135deg, var(--color-primary), var(--color-secondary), var(--color-accent));
    --gradient-hero: radial-gradient(ellipse at bottom, #1a1a2e 0%, #0a0a0f 70%);
    
    /* Glassmorphism */
    --glass-bg: rgba(25, 25, 45, 0.6);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
    
    /* Spacing */
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 1.5rem;
    --space-lg: 2rem;
    --space-xl: 3rem;
    --space-2xl: 5rem;
    
    /* Typography */
    --font-main: 'Montserrat', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-display: 'Playfair Display', Georgia, serif;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-full: 50%;
    
    /* Z-Index */
    --z-notes: 1;
    --z-content: 10;
    --z-nav: 100;
    --z-modal: 1000;
    --z-toast: 1100;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: var(--font-main);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-text);
    background: var(--color-bg-dark);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

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

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

ul, ol {
    list-style: none;
}

address {
    font-style: normal;
}

/* ================================
   Utility Classes
   ================================ */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-md);
}

.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-md);
    box-shadow: var(--glass-shadow);
}

.accent {
    background: var(--gradient-glow);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.required {
    color: var(--color-error);
}

/* ================================
   Floating Musical Notes
   ================================ */
.floating-notes {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: var(--z-notes);
    overflow: hidden;
}

.note {
    position: absolute;
    font-size: 1.5rem;
    opacity: 0.15;
    animation: float-note 15s infinite ease-in-out;
    color: var(--color-primary-light);
    text-shadow: 0 0 10px var(--color-primary);
}

@keyframes float-note {
    0%, 100% {
        transform: translateY(100vh) rotate(0deg);
        opacity: 0;
    }
    10% {
        opacity: 0.15;
    }
    90% {
        opacity: 0.15;
    }
    100% {
        transform: translateY(-100px) rotate(360deg);
        opacity: 0;
    }
}

/* ================================
   Navigation
   ================================ */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: var(--z-nav);
    padding: var(--space-sm) 0;
    background: rgba(10, 10, 15, 0.85);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--glass-border);
    transition: all var(--transition-base);
}

.navbar.scrolled {
    padding: var(--space-xs) 0;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    font-weight: 700;
    font-size: 1.5rem;
    z-index: 101;
}

.logo-icon {
    font-size: 1.8rem;
    color: var(--color-primary);
    animation: pulse-glow 2s ease-in-out infinite;
}

@keyframes pulse-glow {
    0%, 100% {
        text-shadow: 0 0 5px var(--color-primary), 0 0 10px var(--color-primary);
    }
    50% {
        text-shadow: 0 0 20px var(--color-primary), 0 0 40px var(--color-primary);
    }
}

.logo-text {
    background: var(--gradient-glow);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

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

.nav-link {
    position: relative;
    font-weight: 500;
    font-size: 0.95rem;
    padding: var(--space-xs) 0;
    color: var(--color-text-muted);
    transition: color var(--transition-fast);
}

.nav-link:hover,
.nav-link.active {
    color: var(--color-white);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: width var(--transition-base);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

/* Hamburger Menu */
.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    width: 30px;
    height: 30px;
    z-index: 1000;
    position: relative;
}

.hamburger {
    position: relative;
    width: 24px;
    height: 2px;
    background: var(--color-white);
    transition: all var(--transition-fast);
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    width: 24px;
    height: 2px;
    background: var(--color-white);
    transition: all var(--transition-fast);
}

.hamburger::before {
    top: -8px;
}

.hamburger::after {
    top: 8px;
}

.nav-toggle.active .hamburger {
    background: transparent;
}

.nav-toggle.active .hamburger::before {
    top: 0;
    transform: rotate(45deg);
}

.nav-toggle.active .hamburger::after {
    top: 0;
    transform: rotate(-45deg);
}

/* ================================
   Hero Section
   ================================ */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient-hero);
    overflow: hidden;
}

#equalizer-canvas {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 40%;
    opacity: 0.6;
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at center, transparent 0%, var(--color-bg-dark) 70%);
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: var(--z-content);
    text-align: center;
    padding: var(--space-2xl) var(--space-md);
    max-width: 900px;
}

.hero-title {
    font-family: var(--font-display);
    font-size: clamp(2.5rem, 8vw, 5rem);
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: var(--space-md);
}

.title-line {
    display: block;
}

.title-line.accent {
    font-size: 0.9em;
}

.hero-subtitle {
    font-size: clamp(1rem, 2.5vw, 1.3rem);
    color: var(--color-text-muted);
    margin-bottom: var(--space-xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-authority {
    font-size: clamp(0.9rem, 2vw, 1.1rem);
    color: var(--color-secondary);
    font-weight: 500;
    margin-bottom: var(--space-lg);
    letter-spacing: 0.5px;
}

.hero-cta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-md);
    justify-content: center;
    margin-bottom: var(--space-xl);
}

.hero-stats {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-md);
    justify-content: center;
}

.stat-card {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    padding: var(--space-sm) var(--space-md);
    font-size: 0.9rem;
    animation: float 3s ease-in-out infinite;
}

.stat-card:nth-child(2) {
    animation-delay: 0.5s;
}

.stat-card:nth-child(3) {
    animation-delay: 1s;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-10px);
    }
}

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

.scroll-indicator {
    position: absolute;
    bottom: var(--space-lg);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-xs);
    color: var(--color-text-muted);
    font-size: 0.8rem;
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 100% {
        transform: translateX(-50%) translateY(0);
    }
    50% {
        transform: translateX(-50%) translateY(10px);
    }
}

/* ================================
   Buttons
   ================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-xs);
    padding: var(--space-sm) var(--space-lg);
    font-size: 1rem;
    font-weight: 600;
    border-radius: var(--radius-sm);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(45deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transform: translateX(-100%);
    transition: transform 0.5s;
}

.btn:hover::before {
    transform: translateX(100%);
}

.btn-primary {
    /* background: var(--gradient-primary); */
    background: transparent;
    color: var(--color-white);
    box-shadow: 0 4px 15px rgba(255, 77, 252, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px rgba(155, 77, 255, 0.5);
}

.btn-secondary {
    background: transparent;
    color: var(--color-white);
    border: 2px solid var(--color-primary);
}

.btn-secondary:hover {
    background: var(--color-primary);
    box-shadow: 0 4px 15px rgba(155, 77, 255, 0.3);
}

.btn-outline {
    background: transparent;
    color: var(--color-secondary);
    border: 1px solid var(--color-secondary);
}

.btn-outline:hover {
    background: rgba(0, 217, 196, 0.1);
    box-shadow: 0 0 20px rgba(0, 217, 196, 0.2);
}

.btn-full {
    width: 100%;
}

.btn-loader {
    display: none;
    width: 20px;
    height: 20px;
    border: 2px solid transparent;
    border-top-color: var(--color-white);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

.btn.loading .btn-text {
    opacity: 0;
}

.btn.loading .btn-loader {
    display: block;
    position: absolute;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* ================================
   Sections
   ================================ */
.section {
    padding: var(--space-2xl) 0;
    position: relative;
}

.section:nth-child(even) {
    background: var(--color-bg-section);
}

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

.section-title {
    font-family: var(--font-display);
    font-size: clamp(2rem, 5vw, 3rem);
    margin-bottom: var(--space-sm);
}

.section-subtitle {
    color: var(--color-text-muted);
    font-size: 1.1rem;
    max-width: 500px;
    margin: 0 auto;
}

/* ================================
   Classes Section
   ================================ */
.classes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--space-lg);
}

.class-card {
    padding: var(--space-lg);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.class-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-glow);
    transform: scaleX(0);
    transition: transform var(--transition-base);
}

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

.class-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px rgba(155, 77, 255, 0.2);
}

.class-icon {
    font-size: 3rem;
    margin-bottom: var(--space-md);
}

.class-icon svg {
    display: none;
}

.class-title {
    font-size: 1.5rem;
    margin-bottom: var(--space-sm);
    color: var(--color-white);
}

.class-description {
    color: var(--color-text-muted);
    margin-bottom: var(--space-md);
    line-height: 1.7;
}

.class-features {
    margin-bottom: var(--space-lg);
}

.class-features li {
    position: relative;
    padding-left: var(--space-md);
    margin-bottom: var(--space-xs);
    color: var(--color-text);
    font-size: 0.95rem;
}

.class-features li::before {
    content: '✦';
    position: absolute;
    left: 0;
    color: var(--color-secondary);
    font-size: 0.8rem;
}

.class-actions {
    display: flex;
    gap: var(--space-sm);
    flex-wrap: wrap;
}

/* ================================
   Students Worldwide Section
   ================================ */
.students-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: var(--space-lg);
    margin-bottom: var(--space-xl);
}

.student-card {
    padding: var(--space-lg);
    text-align: center;
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.student-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-glow);
    transform: scaleX(0);
    transition: transform var(--transition-base);
}

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

.student-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px rgba(155, 77, 255, 0.2);
}

.student-icon {
    font-size: 2.5rem;
    margin-bottom: var(--space-md);
}

.student-title {
    font-size: 1.15rem;
    color: var(--color-white);
    margin-bottom: var(--space-sm);
    line-height: 1.4;
}

.student-description {
    color: var(--color-text-muted);
    font-size: 0.95rem;
    line-height: 1.7;
}

.authority-line {
    text-align: center;
    font-size: 1.1rem;
    color: var(--color-secondary);
    font-weight: 600;
    margin-top: var(--space-md);
}

/* Staggered animation for students grid */
.students-grid .animate-on-scroll:nth-child(2) {
    transition-delay: 0.1s;
}
.students-grid .animate-on-scroll:nth-child(3) {
    transition-delay: 0.2s;
}
.students-grid .animate-on-scroll:nth-child(4) {
    transition-delay: 0.3s;
}

/* ================================
   Videos Section
   ================================ */
.videos-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--space-lg);
}

.video-card {
    overflow: hidden;
    transition: all var(--transition-base);
    position: relative;
}

.video-card::before {
    content: '';
    position: absolute;
    inset: -2px;
    background: var(--gradient-glow);
    border-radius: var(--radius-md);
    opacity: 0;
    transition: opacity var(--transition-base);
    z-index: -1;
}

.video-card:hover::before {
    opacity: 1;
    animation: glow-pulse 2s infinite;
}

@keyframes glow-pulse {
    0%, 100% {
        opacity: 0.5;
    }
    50% {
        opacity: 1;
    }
}

.video-thumb-link {
    display: block;
    text-decoration: none;
}

.video-wrapper {
    position: relative;
    padding-top: 56.25%;
    background: var(--color-bg-dark);
    overflow: hidden;
}

.video-wrapper iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.video-thumbnail {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-base), filter var(--transition-base);
}

.video-thumb-link:hover .video-thumbnail {
    transform: scale(1.05);
    filter: brightness(0.7);
}

.video-play-btn {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    opacity: 0.85;
    transition: opacity var(--transition-fast), transform var(--transition-fast);
    z-index: 2;
    filter: drop-shadow(0 2px 8px rgba(0, 0, 0, 0.5));
}

.video-thumb-link:hover .video-play-btn {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1.1);
}

.video-info {
    padding: var(--space-md);
}

.video-title {
    font-size: 1.2rem;
    margin-bottom: var(--space-xs);
    color: var(--color-white);
}

.video-caption {
    color: var(--color-text-muted);
    font-size: 0.9rem;
    line-height: 1.6;
}

/* ================================
   Contact Section
   ================================ */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-xl);
    align-items: start;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.info-card {
    display: flex;
    gap: var(--space-md);
    padding: var(--space-md);
    transition: all var(--transition-base);
}

.info-card:hover {
    transform: translateX(5px);
    border-color: var(--color-primary);
}

.info-icon {
    font-size: 1.5rem;
    flex-shrink: 0;
}

.info-content h4 {
    font-size: 1rem;
    color: var(--color-white);
    margin-bottom: var(--space-xs);
}

.info-content address,
.info-content p {
    color: var(--color-text-muted);
    font-size: 0.95rem;
    line-height: 1.6;
}

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

.copy-btn {
    padding: 4px 8px;
    font-size: 0.9rem;
    border-radius: var(--radius-sm);
    background: rgba(155, 77, 255, 0.2);
    color: var(--color-primary-light);
    transition: all var(--transition-fast);
}

.copy-btn:hover {
    background: rgba(155, 77, 255, 0.4);
}

.copy-btn.copied .copy-icon::after {
    content: '✓';
}

.hours-list {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.hours-list li {
    display: flex;
    justify-content: space-between;
    font-size: 0.9rem;
    color: var(--color-text-muted);
}

.hours-list .closed {
    color: var(--color-error);
}

.map-container {
    overflow: hidden;
    padding: 0;
    height: 200px;
}

.map-container iframe {
    width: 100%;
    height: 100%;
    filter: grayscale(100%) invert(92%) contrast(85%);
    opacity: 0.9;
}

/* ================================
   Forms
   ================================ */
.contact-form {
    padding: var(--space-lg);
}

.form-title {
    font-size: 1.5rem;
    margin-bottom: var(--space-lg);
    text-align: center;
    color: var(--color-white);
}

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

.form-group label {
    display: block;
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: var(--space-xs);
    color: var(--color-text);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: var(--space-sm);
    font-family: inherit;
    font-size: 1rem;
    color: var(--color-text);
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(155, 77, 255, 0.2);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--color-text-muted);
    opacity: 0.6;
}

.form-group select {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='%23a0a0b8' viewBox='0 0 16 16'%3E%3Cpath d='M8 11L3 6h10l-5 5z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    padding-right: 36px;
}

.form-group select option {
    background: var(--color-bg-dark);
    color: var(--color-text);
}

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

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

.error-message {
    display: block;
    font-size: 0.8rem;
    color: var(--color-error);
    margin-top: 4px;
    min-height: 1.2em;
}

/* ================================
   Modal
   ================================ */
.modal {
    position: fixed;
    inset: 0;
    z-index: var(--z-modal);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-md);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
}

.modal[hidden] {
    display: none;
}

.modal.active {
    opacity: 1;
    visibility: visible;
}

.modal-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(5px);
}

.modal-content {
    position: relative;
    width: 100%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    padding: var(--space-lg);
    animation: modal-slide-up 0.3s ease;
}

@keyframes modal-slide-up {
    from {
        transform: translateY(20px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.modal-close {
    position: absolute;
    top: var(--space-sm);
    right: var(--space-sm);
    width: 36px;
    height: 36px;
    font-size: 1.5rem;
    color: var(--color-text-muted);
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
}

.modal-close:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--color-white);
}

.modal-title {
    font-size: 1.5rem;
    margin-bottom: var(--space-lg);
    padding-right: var(--space-lg);
}

#modal-class-name {
    color: var(--color-primary-light);
}

/* ================================
   Toast
   ================================ */
.toast {
    position: fixed;
    bottom: var(--space-lg);
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-sm) var(--space-lg);
    background: var(--color-bg-card);
    border: 1px solid var(--color-success);
    border-radius: var(--radius-md);
    box-shadow: 0 10px 40px rgba(0, 210, 106, 0.3);
    z-index: var(--z-toast);
    opacity: 0;
    transition: all var(--transition-base);
}

.toast[hidden] {
    display: none;
}

.toast.active {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
}

.toast-icon {
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-success);
    border-radius: var(--radius-full);
    color: var(--color-white);
    font-size: 0.8rem;
}

.toast-message {
    color: var(--color-text);
    font-size: 0.95rem;
}

/* ================================
   Back to Top
   ================================ */
.back-to-top {
    position: fixed;
    bottom: var(--space-lg);
    right: var(--space-lg);
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    border-radius: var(--radius-full);
    color: var(--color-white);
    font-size: 1.2rem;
    box-shadow: 0 4px 20px rgba(155, 77, 255, 0.4);
    z-index: var(--z-nav);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all var(--transition-base);
}

.back-to-top[hidden] {
    display: block;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 30px rgba(155, 77, 255, 0.5);
}

.back-to-top .arrow {
    display: block;
    animation: arrow-bounce 1s infinite;
}

@keyframes arrow-bounce {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-3px);
    }
}

/* ================================
   Footer
   ================================ */
.footer {
    background: var(--color-bg-dark);
    border-top: 1px solid var(--glass-border);
    padding: var(--space-xl) 0 var(--space-lg);
    text-align: center;
}

.footer-content {
    margin-bottom: var(--space-lg);
}

.footer-logo {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: var(--space-sm);
}

.footer-tagline {
    color: var(--color-text-muted);
    font-size: 0.95rem;
}

.footer-bottom {
    padding-top: var(--space-md);
    border-top: 1px solid var(--glass-border);
}

.copyright {
    color: var(--color-text-muted);
    font-size: 0.85rem;
}

/* ================================
   Animations on Scroll
   ================================ */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.animate-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Staggered animation for grids */
.classes-grid .animate-on-scroll:nth-child(2),
.videos-grid .animate-on-scroll:nth-child(2) {
    transition-delay: 0.15s;
}

/* ================================
   Responsive Design
   ================================ */
@media (max-width: 992px) {
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .map-container {
        height: 250px;
    }
}

@media (max-width: 768px) {
    :root {
        --space-2xl: 3.5rem;
    }
    
    /* Navigation — remove backdrop-filter so it doesn't trap fixed children */
    .navbar {
        backdrop-filter: none;
        -webkit-backdrop-filter: none;
        background: rgba(10, 10, 15, 0.97);
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: var(--space-xl);
        background: #0a0a0f;
        z-index: 999;
        opacity: 0;
        visibility: hidden;
        transform: translateX(100%);
        transition: all var(--transition-base);
    }
    
    .nav-menu.active {
        opacity: 1;
        visibility: visible;
        transform: translateX(0);
    }
    
    .nav-link {
        font-size: 1.4rem;
        color: var(--color-white);
        padding: var(--space-sm) var(--space-lg);
    }
    
    .nav-link:hover,
    .nav-link.active {
        color: var(--color-primary-light);
    }
    
    /* Students Worldwide grid */
    .students-grid {
        grid-template-columns: 1fr 1fr;
    }
    
    /* Hero */
    .hero-stats {
        flex-direction: column;
        align-items: center;
    }
    
    .stat-card {
        width: 100%;
        max-width: 250px;
        justify-content: center;
    }
    
    /* Classes */
    .classes-grid {
        grid-template-columns: 1fr;
    }
    
    .class-actions {
        flex-direction: column;
    }
    
    .class-actions .btn {
        width: 100%;
    }
    
    /* Videos */
    .videos-grid {
        grid-template-columns: 1fr;
    }
    
    /* Contact */
    .contact-info {
        order: 2;
    }
    
    .contact-form-wrapper {
        order: 1;
    }
}

@media (max-width: 480px) {
    :root {
        --space-lg: 1.5rem;
        --space-xl: 2rem;
    }
    
    .hero-cta {
        flex-direction: column;
        width: 100%;
        padding: 0 var(--space-md);
    }
    
    .hero-cta .btn {
        width: 100%;
    }
    
    .btn {
        padding: var(--space-sm) var(--space-md);
        font-size: 0.95rem;
    }
    
    .modal-content {
        padding: var(--space-md);
    }
    
    .back-to-top {
        width: 44px;
        height: 44px;
        right: var(--space-sm);
        bottom: var(--space-sm);
    }
    
    .info-card {
        flex-direction: column;
        text-align: center;
    }
    
    .nav-link {
        font-size: 1.1rem;
    }
    
    .students-grid {
        grid-template-columns: 1fr;
    }
    
    .student-title {
        font-size: 1.05rem;
    }
}

/* ================================
   Reduced Motion
   ================================ */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    html {
        scroll-behavior: auto;
    }
}

/* ================================
   High Contrast
   ================================ */
@media (prefers-contrast: high) {
    :root {
        --glass-bg: rgba(0, 0, 0, 0.9);
        --glass-border: rgba(255, 255, 255, 0.3);
    }
    
    .btn-primary {
        background: var(--color-primary);
    }
    
    .btn-secondary {
        border-width: 3px;
    }
}