:root {
    /* Light Mode Variables (Default) */
    --bg-color: #f7f7f7; /* Light Grey/White */
    --card-bg: #ffffff; /* White */
    --text-primary: #1a202c; /* Dark Grey/Black */
    --text-secondary: #4a5568; /* Medium Grey */
    --accent: #dd8500; /* Darker Orange for contrast on white */
    --accent-glow: rgba(211, 84, 0, 0.1);
    --border-color: #e2e8f0;
    --header-bg-scrolled: rgba(255, 255, 255, 0.8);
    --header-text-scrolled: #1a202c;
    --hero-bg-color: #0a192f; /* Preserved Dark Hero */
    --hero-text-color: #e6f1ff; /* Preserved Light Text for Hero */
    --white: #ffffff;
    --font-main: 'Inter', sans-serif;
    --header-transition: all 0.4s ease;

    scrollbar-gutter: stable;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg-color: #0a192f; /* Deep Navy */
        --card-bg: #112240; /* Lighter Navy */
        --text-primary: #e6f1ff; /* Lightest Slate */
        --text-secondary: #8892b0; /* Slate */
        --accent: #ff9933; /* Orange */
        --accent-glow: rgba(255, 153, 51, 0.2);
        --border-color: #233554;
        --header-bg-scrolled: rgba(10, 25, 47, 0.8);
        --header-text-scrolled: #e6f1ff;
        --accent: #ff9933;
    }
}

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

body {
    font-family: var(--font-main);
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    transition: background-color 0.3s ease, color 0.3s ease;
}

a {
    text-decoration: none;
    color: inherit;
    transition: color 0.3s ease;
}

ul {
    list-style: none;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.main-section {
    padding: 60px 24px;
}

/* Header */
header {
    background-color: transparent; /* Initially transparent blending with hero */
    border-bottom: 1px solid transparent;
    position: fixed; /* Changed from sticky to fixed to overlay hero */
    width: 100%; /* Ensure full width */
    top: 0;
    z-index: 1000;
    padding: 16px 0;
    padding: 16px 0;
    transition: var(--header-transition);
}

header.blurred {
    background-color: rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(10px);
}

header.scrolled {
    background-color: var(--header-bg-scrolled);
    border-bottom: 1px solid var(--border-color);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo a {
    display: flex;
    align-items: center;
    gap: 18px;
}

.peg-logo {
    height: 48px;
    width: auto;
    border-radius: 50%;
    box-shadow: 0 0 10px var(--hero-text-color);
    transition: box-shadow 0.3s ease;
}

.logo-text h1 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--white); /* Always white initially (on dark hero) */
    letter-spacing: -0.02em;
    transition: color 0.3s ease;
}

.logo-text p {
    font-size: 0.75rem;
    color: rgba(255, 255, 255, 0.8); /* Always light initially */
    max-width: 280px;
    line-height: 1.2;
    transition: color 0.3s ease;
}

/* Change header text color when scrolled (if light theme) */
header.scrolled .logo-text h1 {
    color: var(--header-text-scrolled);
}
header.scrolled .logo-text p {
    color: var(--text-secondary);
}

header.scrolled .peg-logo {
    box-shadow: 0 0 10px var(--text-secondary);
}

nav ul {
    display: flex;
    gap: 32px;
}

nav a {
    font-size: 0.9rem;
    font-weight: 500;
    color: rgba(255, 255, 255, 0.8); /* Always light initially */
    transition: color 0.3s ease;
}

nav a:hover, nav a.active {
    color: var(--white);
    text-shadow: 0 0 10px rgba(255,255,255,0.3);
}

header.scrolled nav a {
    color: var(--text-secondary);
    text-shadow: none;
}

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

.uni-logo img {
    height: 55px;
    width: auto;
    opacity: 0.9;
    transition: opacity 0.3s ease, filter 0.3s ease;
    filter: brightness(0) invert(1); /* Start white logo */
}

header.scrolled .uni-logo img {
    filter: none; /* Revert to original colors on white header */
}

/* Specific fix: In Dark Mode, header text stays light when scrolled */
@media (prefers-color-scheme: dark) {
    header.scrolled .logo-text h1 { color: var(--text-primary); }
    header.scrolled .logo-text p { color: var(--text-secondary); }
    header.scrolled nav a { color: var(--text-secondary); }
    header.scrolled nav a:hover { color: var(--accent); }
    header.scrolled .uni-logo img { filter: brightness(0) invert(1); } /* Keep whitespace logo in dark mode */
}

.uni-logo img:hover {
    opacity: 1;
}

/* Hero Section - Preserved Dark Styling */
.hero {
    position: relative;
    padding: 180px 0 160px; /* Increased top padding since fixed header doesn't push it down */
    overflow: hidden;
    margin-top: 0; /* Remove negative margin */
    box-shadow: 0 0 19px 0px rgba(0, 0, 0, 0.5);
}

/* Hero as used in pages other than index */
.hero-pages {
    padding: 120px 0 30px;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    /* CSS-based "Data Driven" Abstract Background - FORCED DARK */
    background-color: var(--hero-bg-color); 
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(255, 153, 51, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 80% 30%, rgba(0, 242, 255, 0.2) 0%, transparent 50%),
        linear-gradient(180deg, #020c1b 0%, #000000 100%);
    background-size: cover;
}

/* Grid overlay */
.hero-bg::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        linear-gradient(#233554 1px, transparent 1px),
        linear-gradient(90deg, #233554 1px, transparent 1px);
    background-size: 40px 40px;
    opacity: 0.12;
}

.hero-content {
    max-width: 1000px;
    z-index: 1;
    text-shadow: 10px 0 20px rgba(0, 0, 0, 1);
}

.eyebrow {
    color: #ff9933;
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 8px;
    display: block;
}

.hero h2 {
    font-size: 4rem;
    line-height: 1.1;
    font-weight: 800;
    color: var(--hero-text-color);
    margin-bottom: 24px;
}

.hero p {
    font-size: 1.25rem;
    color: #d4d5da; /* Forced slate color for hero */
    max-width: 600px;
    margin-bottom: 40px;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.8); /* Lift text off background */
}

/* Buttons */
.cta-group {
    display: flex;
    gap: 16px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 32px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
}

.btn-primary {
    background-color: transparent;
    color: #ff9933;
    border: 1px solid #ff9933;
}

.btn-primary:hover {
    background-color: rgba(255, 153, 51, 0.2);
}

.btn-outline {
    background-color: transparent;
    color: var(--hero-text-color);
    border: 1px solid #8892b0;
}

.btn-outline:hover {
    border-color: var(--hero-text-color);
    background-color: rgba(255,255,255,0.05);
}

/* Common Components */
.read-more {
    color: var(--accent);
    font-weight: 500;
    font-size: 0.9rem;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.read-more .icon-arrow {
    font-size: 1.1rem;
    transition: transform 0.3s ease;
}

.read-more:hover .icon-arrow {
    transform: translateX(4px);
}

/* Footer */
footer {
    background-color: #020c1b; /* Always dark footer */
    padding: 60px 0;
    border-top: 1px solid #233554;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    flex-wrap: wrap;
    gap: 40px;
}

.footer-info h4 {
    color: #e6f1ff;
    margin-bottom: 16px;
    font-size: 1.1rem;
}

.footer-info p {
    color: #8892b0;
    font-size: 0.9rem;
}

.footer-copy {
    color: #8892b0;
    font-size: 0.85rem;
    opacity: 0.7;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    color: var(--white);
    padding: 8px;
    z-index: 1001;
}

header.scrolled .mobile-menu-toggle {
    color: var(--text-primary);
}

@media (prefers-color-scheme: dark) {
    header.scrolled .mobile-menu-toggle {
        color: var(--text-primary);
    }
}

.mobile-menu-toggle .material-symbols-rounded {
    font-size: 28px;
}

/* Responsive Common */
@media (max-width: 768px) {
    .header-container {
        /* Keep row for logo and toggle */
        justify-content: space-between;
        align-items: center;
        flex-wrap: wrap; /* Allow nav to break to next line */
    }
    
    .logo-text {
        display: block;
    }

    .logo-text h1 {
        font-size: 1rem;
        max-width: 200px; /* Ensure it wraps if needed or doesn't push toggle off */
    }

    .logo-text p {
        display: none; /* Hide department details on mobile */
    }

    .peg-logo {
        height: 40px;
    }

    /* Mobile Nav */
    nav {
        display: none; /* Hidden by default */
        width: 100%;
        order: 3; /* Move to bottom */
        margin-top: 16px;
        background-color: var(--bg-color);
        /*background-color: var(--header-bg-scrolled);*/
        /*backdrop-filter: blur(10px);*/
        border-radius: 8px;
        box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
        padding: 16px;
    }

    nav.active {
        display: block;
        animation: slideDown 0.3s ease-out forwards;
    }

    nav ul {
        flex-direction: column;
        align-items: stretch; /* Full width links */
        gap: 8px;
    }

    nav a {
        display: block;
        padding: 12px;
        color: var(--text-primary) !important; /* Force readable text color in dropdown */
        border-radius: 6px;
    }

    nav a:hover, nav a.active {
        background-color: var(--accent-glow);
        color: var(--accent) !important;
        text-shadow: none;
    }

    .mobile-menu-toggle {
        display: block;
    }

    .uni-logo {
        display: none; /* Hide uni logo on mobile to simplify header */
    }

    .hero h2 {
        font-size: 2.5rem;
    }
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Card Component */
.card {
    background-color: var(--card-bg);
    padding: 40px 32px;
    border-radius: 18px;
    box-shadow: 0 10px 30px -15px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
    border: 2px solid var(--border-color);
}
.card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 30px -15px rgba(0, 0, 0, 0.15);
    border-color: var(--accent);
}
.card-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background-color: color-mix(in srgb, var(--accent), transparent 90%);
    color: var(--accent);
    margin-bottom: 24px;
}
.card-icon .material-symbols-rounded {
    font-size: 32px;
}
.card h3 {
    font-size: 1.5rem;
    color: var(--text-primary);
    margin-bottom: 16px;
}
.card p {
    color: var(--text-secondary);
    margin-bottom: 24px;
    font-size: 1rem;
}