/* Custom CSS for a modern, sharp look */
        :root {
            --primary-color: #0d6efd; /* Bootstrap blue for consistency */
            --background-color: #121212;
            --surface-color: #1e1e1e;
            --text-color: #e0e0e0;
            --heading-color: #ffffff;
            --subtle-color: #888;
        }

        html {
            scroll-behavior: smooth;
        }

        body {
            font-family: 'Inter', sans-serif;
            background-color: var(--background-color);
            color: var(--text-color);
            font-weight: 300;
        }

        .navbar {
            background-color: rgba(30, 30, 30, 0.85);
            backdrop-filter: blur(10px);
            -webkit-backdrop-filter: blur(10px);
        }

        .navbar-brand, .nav-link {
            font-weight: 700;
        }

        .nav-link:hover, .nav-link:focus {
            color: var(--primary-color);
        }

        h1, h2, h3, h4, h5, h6 {
            color: var(--heading-color);
            font-weight: 700;
        }

        .section-heading {
            font-weight: 900;
            text-transform: uppercase;
            letter-spacing: 2px;
            color: var(--primary-color);
            margin-bottom: 1rem;
        }

        /* Hero Section */
        #hero {
            min-height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
            text-align: center;
            background-color: var(--background-color);
            background-image: 
                radial-gradient(circle at 25% 30%, rgba(13, 110, 253, 0.1), transparent 30%),
                radial-gradient(circle at 75% 70%, rgba(13, 110, 253, 0.1), transparent 30%);
        }

        #hero h1 {
            font-size: clamp(2.5rem, 8vw, 6rem);
            font-weight: 900;
            line-height: 1.1;
        }

        #hero p {
            font-size: clamp(1rem, 3vw, 1.5rem);
            color: var(--subtle-color);
            font-weight: 300;
        }
        
        /* General Section Styling */
        section {
            padding: 80px 0;
            border-bottom: 1px solid var(--surface-color);
        }

        /* Media Placeholder */
        .media-placeholder {
            width: 100%;
            aspect-ratio: 16 / 9;
            background-color: var(--surface-color);
            border: 2px dashed var(--subtle-color);
            display: flex;
            align-items: center;
            justify-content: center;
            border-radius: 0.5rem;
        }

        .media-placeholder p {
            color: var(--subtle-color);
            font-weight: 700;
        }

        /* Speaker Cards */
        .speaker-card {
            background-color: var(--surface-color);
            border: 1px solid #333;
            border-radius: 0.5rem;
            transition: transform 0.3s ease, box-shadow 0.3s ease;
            color: #ffffff;
        }

        .speaker-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
        }
        
        .speaker-img-placeholder {
            width: 120px;
            height: 120px;
            background-color: #333;
            border-radius: 50%;
            margin: 0 auto 1rem;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        /* Call to Action & Links */
        .cta-section {
            background-color: var(--surface-color);
            border-radius: 0.5rem;
            padding: 2rem;
        }

        .reference-link {
            display: block;
            padding: 1rem;
            background-color: var(--surface-color);
            margin-bottom: 1rem;
            border-radius: 0.5rem;
            text-decoration: none;
            color: var(--text-color);
            transition: background-color 0.3s ease;
        }

        .reference-link:hover {
            background-color: #2a2a2a;
            color: var(--primary-color);
        }
        
        /* Footer */
        footer {
            background-color: var(--background-color);
            padding: 2rem 0;
            text-align: center;
            font-size: 0.9rem;
            color: var(--subtle-color);
        }

        /* Fade-in Animation */
        .fade-in-section {
            opacity: 0;
            transform: translateY(20px);
            transition: opacity 0.6s ease-out, transform 0.6s ease-out;
        }

        .fade-in-section.is-visible {
            opacity: 1;
            transform: translateY(0);
        }