:root {
    /* Color Palette */
    --bg-color: #0f172a;
    /* Deep Slate */
    --surface-color: #1e293b;
    /* Lighter Slate */
    --text-primary: #f1f5f9;
    /* Off-white */
    --text-secondary: #94a3b8;
    /* Muted Grey */
    --accent-primary: #3b82f6;
    /* Vivid Blue */
    --accent-secondary: #06b6d4;
    /* Electric Cyan */

    /* Spacing & Layout */
    --container-width: 1200px;
    --section-spacing: 5rem;
    --border-radius: 12px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* Utilities */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 1.5rem;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.2s ease;
}

ul {
    list-style: none;
}

/* Typography */
h1,
h2,
h3 {
    font-weight: 800;
    letter-spacing: -0.025em;
    color: var(--text-primary);
}

.gradient-text {
    background: linear-gradient(135deg, var(--accent-secondary), var(--accent-primary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-title {
    font-size: 2rem;
    margin-bottom: 2rem;
    text-align: center;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(15, 23, 42, 0.9);
    backdrop-filter: blur(10px);
    z-index: 1000;
    padding: 1rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
}

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

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-secondary);
    font-weight: 600;
}

.nav-links a:hover {
    color: var(--accent-secondary);
}

/* Hero Section */
.hero-section {
    height: 90vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: linear-gradient(rgba(15, 23, 42, 0.8), rgba(15, 23, 42, 0.8)), url('images/hero-bg.png');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
}

.hero-title {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 2.5rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.cta-button {
    display: inline-block;
    background: linear-gradient(135deg, var(--accent-secondary), var(--accent-primary));
    color: white;
    padding: 1rem 2rem;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1.1rem;
    box-shadow: 0 4px 15px rgba(6, 182, 212, 0.3);
}

.cta-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(6, 182, 212, 0.4);
}

/* Section Common */
.section {
    padding: var(--section-spacing) 0;
}

/* About Section */
.about-card {
    background: var(--surface-color);
    padding: 2.5rem;
    border-radius: var(--border-radius);
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
    border: 1px solid rgba(255, 255, 255, 0.05);
}

/* Video Grid */
.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.video-card {
    background: var(--surface-color);
    border-radius: var(--border-radius);
    overflow: hidden;
    transition: transform 0.3s ease;
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.video-card:hover {
    transform: translateY(-5px);
}

.video-thumbnail {
    width: 100%;
    aspect-ratio: 16/9;
    background-color: #334155;
    position: relative;
    object-fit: cover;
}

.video-info {
    padding: 1.5rem;
}

.video-info h3 {
    margin-bottom: 0.5rem;
    font-size: 1.25rem;
}

.video-info p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 1rem;
}

.text-link {
    color: var(--accent-secondary);
    font-weight: 600;
}

.text-link:hover {
    color: var(--accent-primary);
}

/* Footer Connect */
.footer-section {
    padding: 4rem 0;
    text-align: center;
    background: #0b1120;
    margin-top: 4rem;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.social-btn {
    padding: 0.75rem 1.5rem;
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    color: var(--text-primary);
    font-weight: 500;
}

.social-btn:hover {
    background: var(--surface-color);
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

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


/* Mobile Menu Button */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 21px;
    background: transparent;
    border: none;
    cursor: pointer;
    z-index: 1001;
}

.mobile-menu-btn .bar {
    width: 100%;
    height: 3px;
    background-color: var(--text-primary);
    border-radius: 3px;
    transition: all 0.3s ease;
}

/* Mobile Menu Active State (Hamburger Animation) */
.mobile-menu-btn.active .bar:nth-child(1) {
    transform: translateY(9px) rotate(45deg);
}

.mobile-menu-btn.active .bar:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.active .bar:nth-child(3) {
    transform: translateY(-9px) rotate(-45deg);
}

/* Loading State for Videos */
.loading-state {
    grid-column: 1 / -1;
    text-align: center;
    padding: 3rem;
    color: var(--text-secondary);
    font-size: 1.1rem;
    background: var(--surface-color);
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.05);
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    .hero-title {
        font-size: 2.5rem;
    }

    .section-spacing {
        padding: 3rem 0;
    }

    /* Mobile Navigation */
    .mobile-menu-btn {
        display: flex;
    }

    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        height: 100vh;
        width: 70%;
        max-width: 300px;
        background: var(--surface-color);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        transition: right 0.3s ease-in-out;
        box-shadow: -5px 0 15px rgba(0, 0, 0, 0.5);
        padding: 2rem;
        z-index: 1000;
        backdrop-filter: none; /* Removing blur for better performance on mobile menu bg */
    }

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

    .nav-links li {
        margin: 1.5rem 0;
    }

    .nav-links a {
        font-size: 1.25rem;
    }
}