/* BestClassTaker - Modern Design System 2025 */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Modern Color Palette */
    --primary: #0f172a;
    --primary-light: #1e293b;
    --primary-lighter: #334155;
    --accent-blue: #3b82f6;
    --accent-cyan: #06b6d4;
    --accent-purple: #a855f7;
    --accent-orange: #f97316;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    
    /* Neutral Colors */
    --white: #ffffff;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    
    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-3xl: 2rem;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-xs: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    line-height: 1.6;
    color: var(--gray-900);
    background: linear-gradient(135deg, var(--white) 0%, var(--gray-50) 100%);
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Typography System */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

h1 {
    font-size: clamp(2rem, 5vw, 4rem);
    margin-bottom: var(--spacing-lg);
}

h2 {
    font-size: clamp(1.75rem, 4vw, 3rem);
    margin-bottom: var(--spacing-lg);
}

h3 {
    font-size: clamp(1.25rem, 3vw, 1.875rem);
    margin-bottom: var(--spacing-md);
}

p {
    font-size: 1rem;
    line-height: 1.75;
    color: var(--gray-600);
    margin-bottom: var(--spacing-md);
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* Header */
.site-header {
    background: linear-gradient(135deg, #0a0a0f 0%, #0f0a15 100%);
    border-bottom: 1px solid rgba(168, 85, 247, 0.15);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(20px);
    background-color: rgba(10, 10, 15, 0.95);
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md) 0;
}

.logo {
    font-size: 1.5rem;
    font-weight: 900;
    background: linear-gradient(135deg, #a855f7, #ec4899);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.05em;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: var(--spacing-xl);
}

.nav-links a {
    color: #d1d5db;
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    transition: color var(--transition-fast);
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, #a855f7, #ec4899);
    transition: width var(--transition-fast);
}

.nav-links a:hover {
    background: linear-gradient(135deg, #a855f7, #ec4899);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links a:hover::after {
    width: 100%;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-lg);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.95rem;
    transition: all var(--transition-base);
    border: none;
    cursor: pointer;
    position: relative;
    overflow: hidden;
    letter-spacing: 0.5px;
}

.btn::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(45deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transform: translateX(-100%);
    transition: transform 0.6s;
}

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

.btn-primary {
    background: linear-gradient(135deg, var(--accent-blue), var(--accent-cyan));
    color: var(--white);
    box-shadow: 0 10px 30px rgba(59, 130, 246, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 15px 40px rgba(59, 130, 246, 0.4);
}

.btn-secondary {
    background: var(--gray-100);
    color: var(--accent-blue);
    border: 2px solid var(--accent-blue);
}

.btn-secondary:hover {
    background: var(--accent-blue);
    color: var(--white);
    transform: translateY(-2px);
}

/* Sections */
section {
    padding: var(--spacing-3xl) var(--spacing-lg);
}

section h2 {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
    position: relative;
    display: inline-block;
    width: 100%;
}

section h2::after {
    content: '';
    position: absolute;
    bottom: -12px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--accent-blue), var(--accent-cyan));
    border-radius: var(--radius-full);
}

/* Badges */
.badge {
    display: inline-block;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.5px;
    text-transform: uppercase;
}

.badge-primary {
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1), rgba(6, 182, 212, 0.1));
    color: var(--accent-blue);
    border: 1px solid rgba(59, 130, 246, 0.3);
}

.badge-success {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
    border: 1px solid rgba(16, 185, 129, 0.3);
}

/* Grid System */
.grid {
    display: grid;
    gap: var(--spacing-xl);
}

.grid-2 {
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid-3 {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

.grid-4 {
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

/* Flex Utilities */
.flex {
    display: flex;
}

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

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

.flex-col {
    flex-direction: column;
}

.gap-md {
    gap: var(--spacing-md);
}

.gap-lg {
    gap: var(--spacing-lg);
}

.gap-xl {
    gap: var(--spacing-xl);
}

/* Responsive */
@media (max-width: 768px) {
    .nav-links {
        gap: var(--spacing-lg);
        font-size: 0.85rem;
    }

    section {
        padding: var(--spacing-2xl) var(--spacing-md);
    }

    h1 {
        font-size: 1.75rem;
    }

    h2 {
        font-size: 1.5rem;
    }

    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }
}

/* Footer */
.site-footer {
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: var(--white);
    padding: var(--spacing-3xl) var(--spacing-lg);
    text-align: center;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-links {
    list-style: none;
    display: flex;
    justify-content: center;
    gap: var(--spacing-xl);
    margin-top: var(--spacing-lg);
    flex-wrap: wrap;
}

.footer-links a {
    color: var(--gray-300);
    text-decoration: none;
    transition: color var(--transition-fast);
}

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

.footer-contact {
    margin: var(--spacing-lg) 0;
    padding: var(--spacing-lg) 0;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-contact p {
    font-size: 0.95rem;
    color: var(--gray-200);
    margin: 0;
    font-weight: 500;
}

.footer-social {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin: var(--spacing-lg) 0;
}

.social-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    color: var(--white);
    transition: all var(--transition-fast);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.social-icon svg {
    width: 20px;
    height: 20px;
}

.social-icon:hover {
    background: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.4);
    transform: translateY(-2px);
}

.social-icon.instagram:hover {
    background: linear-gradient(45deg, #f09433 0%, #e6683c 25%, #dc2743 50%, #cc2366 75%, #bc1888 100%);
    border-color: transparent;
}

.social-icon.facebook:hover {
    background: #1877f2;
    border-color: transparent;
}

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

::-webkit-scrollbar-track {
    background: var(--gray-100);
}

::-webkit-scrollbar-thumb {
    background: var(--accent-blue);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-cyan);
}

/* Stats Bar - Dark Theme */
.stats-bar {
    background: linear-gradient(135deg, #0a0a0f 0%, #0f0a15 50%, #0a0a0f 100%);
    padding: var(--spacing-3xl) var(--spacing-lg) !important;
    position: relative;
    overflow: hidden;
}

.stats-bar::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 20% 50%, rgba(168, 85, 247, 0.1) 0%, transparent 50%),
                radial-gradient(circle at 80% 80%, rgba(236, 72, 153, 0.1) 0%, transparent 50%);
    pointer-events: none;
}

.stats-grid {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-2xl);
}

.stat-card {
    text-align: center;
    animation: slideUp 0.8s ease-out both;
    padding: var(--spacing-xl);
    background: linear-gradient(135deg, rgba(168, 85, 247, 0.08), rgba(236, 72, 153, 0.05));
    backdrop-filter: blur(10px);
    border-radius: var(--radius-xl);
    border: 1px solid rgba(168, 85, 247, 0.25);
    transition: all var(--transition-base);
}

.stat-card:nth-child(1) { animation-delay: 0.1s; }
.stat-card:nth-child(2) { animation-delay: 0.2s; }
.stat-card:nth-child(3) { animation-delay: 0.3s; }
.stat-card:nth-child(4) { animation-delay: 0.4s; }

.stat-card:hover {
    transform: translateY(-8px);
    background: linear-gradient(135deg, rgba(168, 85, 247, 0.12), rgba(236, 72, 153, 0.08));
    border-color: rgba(168, 85, 247, 0.4);
    box-shadow: 0 12px 30px rgba(168, 85, 247, 0.15);
}

.stat-value {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 900;
    background: linear-gradient(135deg, #a855f7, #ec4899);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--spacing-sm);
    animation: slideUp 0.8s ease-out 0.1s both;
}

.stat-label {
    font-size: 0.95rem;
    color: #d1d5db;
    font-weight: 600;
    letter-spacing: 0.5px;
    animation: slideUp 0.8s ease-out 0.2s both;
}