:root {
    /* Academic Palette */
    --primary-color: #002147; /* Oxford Blue */
    --secondary-color: #A41034; /* Harvard Crimson */
    --accent-color: #2A5CAA; /* Lighter Blue */
    --text-color: #333333;
    --light-text: #666666;
    --bg-color: #ffffff;
    --bg-alt: #f8f9fa; /* Very light grey */
    --border-color: #e1e4e8;

    --font-heading: 'Merriweather', serif;
    --font-body: 'Inter', sans-serif;

    --container-width: 1100px;
    --border-radius: 4px;
}

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

body {
    font-family: var(--font-body);
    color: var(--text-color);
    line-height: 1.7;
    background-color: var(--bg-color);
    font-size: 16px;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    color: var(--primary-color);
    margin-bottom: 1rem;
    line-height: 1.3;
}

p {
    margin-bottom: 1.5rem;
}

a {
    color: var(--accent-color);
    text-decoration: none;
    transition: color 0.2s ease;
}

a:hover {
    color: var(--primary-color);
}

.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* Header / Hero Section */
header {
    background-color: #fff;
    border-bottom: 1px solid var(--border-color);
    padding: 60px 0 60px;
    text-align: center;
    position: relative;
}

header h1 {
    font-size: 2.8rem;
    font-weight: 700;
    color: var(--primary-color);
    max-width: 900px;
    margin: 0 auto 30px;
    letter-spacing: -0.5px;
}

/* Author List Styling */
.authors-container {
    max-width: 900px;
    margin: 0 auto 30px;
}

.authors-list {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    color: var(--text-color);
    margin-bottom: 15px;
    line-height: 1.4;
}

.author-name {
    display: inline-block;
}

.affiliations-list {
    font-size: 0.85rem;
    color: var(--light-text);
    line-height: 1.4;
    margin-bottom: 10px;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px 16px;
}

.affiliation {
    display: inline-block;
}

.author-notes {
    font-size: 0.8rem;
    color: var(--light-text);
    font-style: italic;
    margin-top: 10px;
}

.author-notes p {
    margin-bottom: 5px;
}

.header-buttons {
    display: flex;
    justify-content: center;
    gap: 20px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 28px;
    border-radius: var(--border-radius);
    font-family: var(--font-body);
    font-weight: 500;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.2s ease;
    gap: 8px;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
    border: 1px solid var(--primary-color);
}

.btn-primary:hover {
    background-color: #00152e;
    color: white;
}

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

.btn-outline:hover {
    background-color: var(--bg-alt);
}

.btn-small {
    padding: 8px 16px;
    font-size: 0.9rem;
}

/* Sections */
section {
    padding: 80px 0;
}

.bg-light {
    background-color: var(--bg-alt);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.section-title {
    text-align: center;
    font-size: 2.2rem;
    margin-bottom: 50px;
    position: relative;
    padding-bottom: 15px;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background-color: var(--secondary-color);
}

.lead-text {
    font-size: 1.15rem;
    text-align: center;
    max-width: 800px;
    margin: 0 auto 50px;
    color: var(--light-text);
}

/* Abstract & Metrics */
.paper-abstract {
    background-color: #fff;
    border: 1px solid var(--border-color);
    padding: 40px;
    border-radius: var(--border-radius);
    box-shadow: 0 4px 20px rgba(0,0,0,0.03);
    margin-bottom: 50px;
}

.paper-abstract p {
    margin-bottom: 15px;
    text-align: justify;
}

.paper-abstract strong {
    color: var(--primary-color);
}

.metrics {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 20px;
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
    padding: 30px 0;
}

.metric {
    flex: 1;
    min-width: 200px;
    text-align: center;
    padding: 0 15px;
    border-right: 1px solid var(--border-color);
}

.metric:last-child {
    border-right: none;
}

.metric-value {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--secondary-color);
    font-family: var(--font-heading);
    margin-bottom: 5px;
}

.metric-label {
    font-size: 0.9rem;
    color: var(--light-text);
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: 600;
}

/* Cards */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
}

.card {
    background-color: white;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 30px;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    display: flex;
    flex-direction: column;
}

.card:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
    border-color: var(--accent-color);
}

.card-icon {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.card h3 {
    font-size: 1.4rem;
    margin-bottom: 15px;
}

.card p {
    color: var(--light-text);
    font-size: 0.95rem;
    margin-bottom: 0;
}

.highlight-box {
    background-color: #fff;
    border-left: 4px solid var(--secondary-color);
    padding: 30px;
    margin-top: 50px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.03);
}

.highlight-box h3 {
    font-size: 1.3rem;
    display: flex;
    align-items: center;
    gap: 10px;
}

.highlight-box h3 i {
    color: var(--secondary-color);
}

.highlight-box p {
    margin-bottom: 0;
}

/* Demo & Video */
.demo-link {
    text-align: center;
    margin: 40px 0;
}

.video-container {
    position: relative;
    width: 100%;
    height: 0;
    padding-bottom: 56.25%;
    background-color: #000;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
    margin-bottom: 60px;
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

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

.resource-card {
    text-align: center;
}

.resource-card h3 {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.resource-card .btn {
    margin-top: 15px;
}

/* Footer */
footer {
    background-color: var(--primary-color);
    color: rgba(255,255,255,0.8);
    padding: 80px 0 40px;
    font-size: 0.95rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 60px;
}

.footer-section h3 {
    color: white;
    font-size: 1.1rem;
    margin-bottom: 25px;
    padding-bottom: 10px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-section p {
    margin-bottom: 10px;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 10px;
}

.footer-links a {
    color: rgba(255,255,255,0.8);
    transition: color 0.2s;
}

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

.footer-section a[href^="mailto"] {
    color: white;
    text-decoration: underline;
}

.copyright {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255,255,255,0.1);
    font-size: 0.85rem;
    color: rgba(255,255,255,0.5);
}

/* Responsive */
@media (max-width: 768px) {
    header h1 {
        font-size: 2.2rem;
    }
    
    .metrics {
        flex-direction: column;
        gap: 0;
    }
    
    .metric {
        border-right: none;
        border-bottom: 1px solid var(--border-color);
        padding: 20px 0;
    }
    
    .metric:last-child {
        border-bottom: none;
    }
}