/* ===== Skilliify Premium Education Theme ===== */
:root,
[data-theme="light"] {
    /* Refined Light Theme Palette - Slate/Indigo base */
    --bg-main: #fcfdfe;
    --bg-main-rgb: 252, 253, 254;
    --bg-surface: #ffffff;
    --bg-surface-rgb: 255, 255, 255;
    --bg-element: #f1f5f9;
    --bg-element-rgb: 241, 245, 249;

    --text-main: #0f172a;
    --text-muted: #475569;
    --text-dim: #94a3b8;

    --border-color: #e2e8f0;
    --border-light: #f1f5f9;

    /* Advanced Shadow System */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.02);
    --shadow-md: 0 10px 25px -5px rgba(0, 0, 0, 0.04), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
    --shadow-lg: 0 20px 50px -12px rgba(0, 0, 0, 0.08);
    --shadow-glow: 0 0 20px rgba(var(--primary-rgb), 0.3);

    --glass-bg: rgba(255, 255, 255, 0.8);
    --glass-border: rgba(255, 255, 255, 0.2);

    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.7s cubic-bezier(0.4, 0, 0.2, 1);

    --radius-sm: 12px;
    --radius-md: 20px;
    --radius-lg: 32px;
    --radius-full: 100px;
}

[data-theme="dark"] {
    /* Premium Dark Theme - Deep Blue/Slate */
    --bg-main: #050914;
    --bg-main-rgb: 5, 9, 20;
    --bg-surface: #0a1120;
    --bg-surface-rgb: 10, 17, 32;
    --bg-element: #111a2e;
    --bg-element-rgb: 17, 26, 46;

    --header-bg: rgba(5, 9, 20, 0.8);

    --text-main: #f1f5f9;
    --text-muted: #94a3b8;
    --text-dim: #64748b;

    --border-color: #1e293b;
    --border-light: #0f172a;

    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 12px 30px -5px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 30px 60px -12px rgba(0, 0, 0, 0.6);

    --glass-bg: rgba(10, 17, 32, 0.75);
    --glass-border: rgba(255, 255, 255, 0.05);
}

/* Color Palette System - Using RGB for opacity support */
:root,
[data-color="orange"] {
    --primary: #f97316;
    --primary-rgb: 249, 115, 22;
    --primary-light: #fb923c;
    --primary-dark: #ea580c;
    --secondary: #0f172a;
    --accent: #fbbf24;
    --gradient-primary: linear-gradient(135deg, #f97316, #fb923c);
}

[data-color="ocean"] {
    --primary: #0ea5e9;
    --primary-rgb: 14, 165, 233;
    --primary-light: #38bdf8;
    --primary-dark: #0284c7;
    --secondary: #0f172a;
    --accent: #10b981;
    --gradient-primary: linear-gradient(135deg, #0ea5e9, #38bdf8);
}

[data-color="forest"] {
    --primary: #10b981;
    --primary-rgb: 16, 185, 129;
    --primary-light: #34d399;
    --primary-dark: #059669;
    --secondary: #064e3b;
    --accent: #fbbf24;
    --gradient-primary: linear-gradient(135deg, #10b981, #34d399);
}

[data-color="purple"] {
    --primary: #8b5cf6;
    --primary-rgb: 139, 92, 246;
    --primary-light: #a78bfa;
    --primary-dark: #7c3aed;
    --secondary: #2e1065;
    --accent: #f472b6;
    --gradient-primary: linear-gradient(135deg, #8b5cf6, #a78bfa);
}

[data-color="ruby"] {
    --primary: #e11d48;
    --primary-rgb: 225, 29, 72;
    --primary-light: #fb7185;
    --primary-dark: #be123c;
    --secondary: #4c0519;
    --accent: #fbbf24;
    --gradient-primary: linear-gradient(135deg, #e11d48, #fb7185);
}

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

html {
    scroll-behavior: smooth;
    overflow-x: hidden;
    width: 100%;
}

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-main);
    color: var(--text-main);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
    overflow-x: hidden;
    width: 100%;
    position: relative;
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 10px;
}
::-webkit-scrollbar-track {
    background: var(--bg-main);
}
::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 5px;
    border: 3px solid var(--bg-main);
}
::-webkit-scrollbar-thumb:hover {
    background: var(--text-dim);
}

/* Modern Utilities */
.glass {
    background: var(--glass-bg);
    backdrop-filter: blur(12px) saturate(180%);
    -webkit-backdrop-filter: blur(12px) saturate(180%);
    border: 1px solid var(--glass-border);
}

.text-gradient {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    padding-right: 4px;
    padding-bottom: 4px;
}

.shimmer {
    background: linear-gradient(90deg, 
        rgba(255,255,255,0) 0%, 
        rgba(255,255,255,0.2) 50%, 
        rgba(255,255,255,0) 100%);
    background-size: 200% 100%;
    animation: shimmer 2s infinite;
}

.text-gradient.shimmer {
    background: linear-gradient(90deg, 
        var(--primary) 0%, 
        var(--primary-light) 40%, 
        #ffffff 50%,
        var(--primary-light) 60%, 
        var(--primary) 100%);
    background-size: 200% auto;
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: shimmer 3s linear infinite;
}

@keyframes shimmer {
    0% { background-position: -200% center; }
    100% { background-position: 200% center; }
}

/* Animations */
.reveal-up {
    opacity: 0;
    transform: translateY(30px);
    transition: var(--transition-slow);
}

.reveal-up.active {
    opacity: 1;
    transform: translateY(0);
}

/* Buttons */
.btn {
    padding: 12px 28px;
    border-radius: var(--radius-sm);
    font-weight: 600;
    font-size: 15px;
    text-decoration: none;
    transition: var(--transition-base);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    cursor: pointer;
    border: none;
    letter-spacing: -0.01em;
}

.btn-primary {
    background: var(--gradient-primary);
    color: #fff;
    box-shadow: 0 10px 20px -5px rgba(var(--primary-rgb), 0.4);
}

.btn-primary:hover {
    transform: translateY(-4px);
    box-shadow: 0 15px 30px -8px rgba(var(--primary-rgb), 0.5);
    filter: brightness(1.1);
}

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

.btn-outline:hover {
    border-color: var(--primary);
    background: rgba(var(--primary-rgb), 0.05);
    color: var(--primary);
    transform: translateY(-4px);
}

/* Header & Nav */
.header-glass {
    background: var(--glass-bg);
    border-bottom: 1px solid var(--glass-border);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    height: 80px;
    position: sticky;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    display: flex;
    align-items: center;
}

.sticky-nav {
    position: sticky;
    top: 0;
    z-index: 1000;
}

/* Background Slider on all pages */
.page-bg-slider {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -10;
    overflow: hidden;
}

.slide {
    position: absolute;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    opacity: 0;
    transition: opacity 2s ease-in-out, transform 10s linear;
    transform: scale(1.1);
}

.slide.active {
    opacity: 0.15; /* Sublte background effect */
    transform: scale(1);
}

[data-theme="dark"] .slide.active {
    opacity: 0.08;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: nowrap;
}

.nav-links a {
    color: var(--text-main);
    text-decoration: none;
    font-weight: 600;
    font-size: 14px;
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    transition: var(--transition-fast);
    white-space: nowrap;
}

.nav-links a:hover {
    color: var(--primary);
    background: rgba(var(--primary-rgb), 0.05);
}

/* Mobile Menu Button - Hidden on Desktop */
.mobile-menu-btn {
    display: none !important;
    background: none;
    border: none;
    color: var(--text-main);
    font-size: 24px;
    cursor: pointer;
    padding: 8px;
    z-index: 1100;
}

/* Responsive Navigation */
@media (max-width: 1024px) {
    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 300px;
        height: 100vh;
        background: var(--bg-surface);
        flex-direction: column;
        justify-content: center;
        padding: 80px 40px;
        transition: 0.4s ease-in-out;
        z-index: 1050;
        box-shadow: -10px 0 30px rgba(0,0,0,0.1);
        gap: 20px;
    }

    .nav-links.active {
        right: 0;
    }

    .mobile-menu-btn {
        display: block !important;
    }

    .nav-links .theme-controls {
        margin-left: 0 !important;
        margin-top: 20px;
        width: 100%;
        justify-content: center;
    }

    .nav-links .btn {
        width: 100%;
        margin-left: 0 !important;
    }
}

/* Announcement Marquee Fix */
.announcement-marquee {
    width: 100%;
    min-height: 48px;
    z-index: 900;
    overflow: hidden;
    display: flex;
    align-items: center;
}

.announcement-marquee marquee {
    width: 100%;
    height: 48px;
    line-height: 48px;
}

.announcement-marquee span {
    display: inline-block;
    vertical-align: middle;
}

/* Cards */
.premium-card {
    background: var(--bg-surface);
    border-radius: var(--radius-md);
    padding: 32px;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-md);
    transition: var(--transition-base);
}

.premium-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: rgba(var(--primary-rgb), 0.2);
}

/* Hero Section Refined */
.hero {
    position: relative;
    padding: 160px 5% 100px;
    min-height: 90vh;
}

.hero-blob {
    position: absolute;
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(var(--primary-rgb), 0.15) 0%, rgba(var(--primary-rgb), 0) 70%);
    filter: blur(60px);
    z-index: -1;
    animation: blob-float 20s infinite alternate;
}

@keyframes blob-float {
    0% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(30px, -50px) scale(1.1); }
    66% { transform: translate(-20px, 20px) scale(0.9); }
    100% { transform: translate(0, 0) scale(1); }
}

.hero h1 {
    font-size: 64px;
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: 24px;
    letter-spacing: -0.03em;
}

@media (max-width: 768px) {
    .hero {
        padding: 120px 5% 60px;
        min-height: auto;
    }
    
    .hero h1 { font-size: 32px; }
    
    .header-glass { height: 70px; }

    /* Wrap the extra flex block for mode toggles */
    .nav-links>div {
        margin-left: 0 !important;
        padding: 20px;
        width: 100%;
        justify-content: space-between !important;
        gap: 15px !important;
        border-bottom: 1px solid var(--border-color);
        background: var(--bg-element);
    }

    /* Make sections tighter */
    .section {
        padding: 60px 20px;
    }
    
    .section-title {
        margin-bottom: 40px;
    }
    
    .section-title h2 {
        font-size: 28px;
    }

    .stats {
        padding: 40px 20px;
        gap: 24px;
    }
    
    .stat-item {
        min-width: 140px;
        padding: 10px;
    }
    
    .stat-item h3 {
        font-size: 36px;
    }
    
    .course-modal-content {
        padding: 50px 24px 24px;
        width: 95%;
    }
    
    .course-modal-title {
        font-size: 24px;
    }
}

/* ===== Statistics Section ===== */
.stats {
    background: var(--bg-surface);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-around;
    padding: 60px 5%;
    text-align: center;
    flex-wrap: wrap;
    gap: 40px;
    position: relative;
    z-index: 10;
}

.stat-item {
    flex: 1;
    min-width: 200px;
    padding: 20px;
    transition: var(--transition-base);
}

.stat-item:hover {
    transform: translateY(-5px);
}

.stat-item h3 {
    font-size: 52px;
    font-weight: 800;
    margin-bottom: 8px;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.stat-item p {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

/* ===== Course Grid & Cards ===== */
.section {
    padding: 120px 5%;
    position: relative;
}

.section-alt {
    background-color: var(--bg-element);
}

.section-title {
    text-align: center;
    margin-bottom: 80px;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.section-title h2 {
    font-size: 42px;
    font-weight: 900;
    letter-spacing: -0.02em;
    margin-bottom: 16px;
}

.section-title .underline {
    width: 80px;
    height: 4px;
    background: var(--gradient-primary);
    margin: 0 auto 24px;
    border-radius: 2px;
}

.course-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(100%, 280px), 1fr));
    gap: 40px;
}

.course-card {
    background: var(--bg-surface);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    padding: 12px;
    transition: var(--transition-base);
    display: flex;
    flex-direction: column;
    height: 100%;
}

.course-card:hover {
    transform: translateY(-12px);
    box-shadow: var(--shadow-lg);
    border-color: rgba(var(--primary-rgb), 0.3);
}

.course-img {
    height: 240px;
    background: var(--bg-element);
    border-radius: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    margin-bottom: 24px;
    position: relative;
}

.course-img i {
    font-size: 64px;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    transition: var(--transition-base);
}

.course-card:hover .course-img i {
    transform: scale(1.1) rotate(5deg);
}

.course-info {
    padding: 12px 20px 24px;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.course-info h3 {
    font-size: 24px;
    font-weight: 800;
    margin-bottom: 12px;
    color: var(--text-main);
}

.course-info p {
    font-size: 15px;
    color: var(--text-muted);
    margin-bottom: 24px;
    line-height: 1.6;
}

/* ===== Course Modal ===== */
.course-modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(5, 9, 20, 0.8);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-base);
}

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

.course-modal-content {
    background: var(--bg-surface);
    border-radius: var(--radius-lg);
    padding: 60px 40px 40px;
    max-width: 600px;
    width: 90%;
    position: relative;
    transform: translateY(40px) scale(0.95);
    transition: var(--transition-base);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-lg);
}

.course-modal-overlay.active .course-modal-content {
    transform: translateY(0) scale(1);
}

.course-modal-close {
    position: absolute;
    top: 24px;
    right: 24px;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--bg-element);
    border: none;
    color: var(--text-main);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition-fast);
}

.course-modal-close:hover {
    background: var(--primary);
    color: white;
    transform: rotate(90deg);
}

.course-modal-title {
    font-size: 32px;
    font-weight: 900;
    margin-bottom: 20px;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.course-modal-body {
    font-size: 17px;
    color: var(--text-muted);
    line-height: 1.7;
}

/* ===== Footer ===== */
footer {
    background: var(--bg-surface);
    padding: 100px 5% 40px;
    border-top: 1px solid var(--border-color);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 60px;
    margin-bottom: 80px;
}

.footer-col h4 {
    font-size: 20px;
    font-weight: 800;
    margin-bottom: 28px;
    color: var(--text-main);
}

.footer-col ul {
    list-style: none;
}

.footer-col ul li {
    margin-bottom: 16px;
}

.footer-col ul li a {
    color: var(--text-muted);
    text-decoration: none;
    transition: var(--transition-fast);
    font-weight: 500;
}

.footer-col ul li a:hover {
    color: var(--primary);
    padding-left: 8px;
}

.footer-bottom {
    padding-top: 40px;
    border-top: 1px solid var(--border-color);
    text-align: center;
    color: var(--text-dim);
    font-size: 14px;
    font-weight: 500;
}