/* Brand color tokens (ARCH blue -> teal, matching the submission platform) */
:root {
    --brand: #2563eb;          /* primary brand blue (decorative / large headings) */
    --brand-dark: #0d9488;     /* secondary brand teal (gradient end) */
    --brand-link: #1d4ed8;     /* darker blue for small/interactive text — WCAG AA (6.3:1 on white) */
    --brand-slate: #384446;    /* ARCH logo slate (letters, dark accents) */
}

/* CSS Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #ffffff;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header Styles */
.header {
    background: linear-gradient(135deg, #2563eb 0%, #0d9488 100%);
    color: white;
    padding: 2rem 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.header-content {
    text-align: center;
    margin-bottom: 2rem;
}

.logo {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    letter-spacing: -0.02em;
}

.tagline {
    font-size: 1.2rem;
    opacity: 0.9;
    font-weight: 300;
}

.nav-list {
    display: flex;
    justify-content: center;
    list-style: none;
    gap: 2rem;
    flex-wrap: wrap;
}

.nav-list a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 25px;
    transition: all 0.3s ease;
}

.nav-list a:hover {
    background-color: rgba(255,255,255,0.2);
    transform: translateY(-2px);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #f5f7fa 0%, #c2ddd9 100%);
    padding: 6rem 0;
    text-align: center;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: #2d3748;
    line-height: 1.2;
}

.hero-description {
    font-size: 1.3rem;
    color: #4a5568;
    max-width: 800px;
    margin: 0 auto 3rem;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    display: inline-block;
    padding: 1rem 2rem;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 1.1rem;
}

.btn-primary {
    background: linear-gradient(135deg, #2563eb 0%, #0d9488 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(37, 99, 235, 0.4);
}

.btn-secondary {
    background: white;
    color: #2563eb;
    border: 2px solid #2563eb;
}

.btn-secondary:hover {
    background: #2563eb;
    color: white;
    transform: translateY(-3px);
}

/* Section Styles */
.section-title {
    font-size: 2.5rem;
    font-weight: 600;
    text-align: center;
    margin-bottom: 3rem;
    color: #2d3748;
}

.section-description {
    text-align: center;
    font-size: 1.2rem;
    color: #4a5568;
    max-width: 600px;
    margin: 0 auto 3rem;
}

/* About Section */
.about {
    padding: 6rem 0;
    background: white;
}

.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-text p {
    font-size: 1.1rem;
    color: #4a5568;
    margin-bottom: 1.5rem;
}

.about-stats {
    display: grid;
    gap: 2rem;
}

.stat,
.repo-card {
    text-align: center;
    padding: 2rem;
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
    border-radius: 15px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}

.stat-number {
    display: block;
    font-size: 3rem;
    font-weight: 700;
    color: #2563eb;
    margin-bottom: 0.5rem;
}

.stat-label {
    color: #4a5568;
    font-weight: 500;
}

/* AAAI 2026 Lab Section */
.aaai2026 {
    padding: 6rem 0;
    background: white;
}

.aaai2026-header {
    text-align: center;
    margin-bottom: 3rem;
}

.aaai2026-meta {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 2rem;
}

.aaai2026-meta-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.1rem;
    color: #4a5568;
}

.aaai2026-meta-item strong {
    color: #2d3748;
}

.aaai2026-links {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.aaai2026-link {
    color: #2563eb;
    text-decoration: none;
    padding: 0.5rem 1rem;
    border: 1px solid #2563eb;
    border-radius: 20px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.aaai2026-link:hover {
    background: #2563eb;
    color: white;
}

.aaai2026-organizers {
    font-size: 0.95rem;
    color: #4a5568;
    max-width: 900px;
    margin: 0 auto 3rem;
    text-align: center;
    line-height: 2.2;
}

/* Researcher Links */
.researcher-link {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

.researcher-link:hover {
    color: #0d9488;
    text-decoration: underline;
}

.scholar-icon {
    display: inline-block;
    width: 16px;
    height: 16px;
    margin-left: 4px;
    vertical-align: middle;
    opacity: 0.7;
    transition: opacity 0.2s ease;
}

.scholar-icon:hover {
    opacity: 1;
}

/* Ensure scholar icon link stays visible after click/visited */
a[title="Google Scholar"] {
    display: inline;
}

a[title="Google Scholar"]:visited .scholar-icon,
a[title="Google Scholar"]:active .scholar-icon {
    display: inline-block;
    opacity: 0.7;
}

.speaker-link {
    color: #4a5568;
    text-decoration: none;
    border-bottom: 1px dotted #2563eb;
    transition: all 0.2s ease;
}

.speaker-link:hover {
    color: #2563eb;
    border-bottom-style: solid;
}

/* Program Schedule Table */
.program-section {
    margin-bottom: 3rem;
}

.program-section-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: #2d3748;
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #2563eb;
}

.program-table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
}

.program-table th {
    background: linear-gradient(135deg, #2563eb 0%, #0d9488 100%);
    color: white;
    padding: 1rem;
    text-align: left;
    font-weight: 600;
}

.program-table td {
    padding: 1rem;
    border-bottom: 1px solid #e2e8f0;
    vertical-align: top;
}

.program-table tr:last-child td {
    border-bottom: none;
}

.program-table tr:hover:not(.program-break) {
    background-color: #f7fafc;
}

.program-break {
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
}

.program-break td {
    text-align: center;
    font-weight: 600;
    color: #2563eb;
    padding: 1.5rem;
}

.program-time {
    font-weight: 500;
    color: #2563eb;
    white-space: nowrap;
}

.program-topic {
    font-weight: 500;
    color: #2d3748;
}

.program-topic-desc {
    font-size: 0.9rem;
    color: #718096;
    margin-top: 0.25rem;
}

.program-speaker {
    color: #4a5568;
}

.program-resources {
    min-width: 100px;
}

.colab-link {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    padding: 0.25rem 0.75rem;
    background: #f7fafc;
    color: #2563eb;
    text-decoration: none;
    border-radius: 15px;
    font-size: 0.85rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.colab-link:hover {
    background: #2563eb;
    color: white;
}

/* Responsive Table */
@media (max-width: 768px) {
    .program-table {
        font-size: 0.9rem;
    }

    .program-table th,
    .program-table td {
        padding: 0.75rem 0.5rem;
    }

    /* Keep the Resources column (Colab/slides/eval links) visible; allow horizontal scroll instead of hiding it */
    .program-table {
        display: block;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
    }

    .aaai2026-meta {
        flex-direction: column;
        align-items: center;
        gap: 0.75rem;
    }
}

@media (max-width: 480px) {
    .program-table {
        display: block;
        overflow-x: auto;
    }

    .program-section-title {
        font-size: 1.25rem;
    }
}

/* VNN-COMP 2026 Section */
.vnncomp2026 {
    padding: 6rem 0;
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
}

.vnncomp2026-header {
    text-align: center;
    margin-bottom: 3rem;
}

.vnncomp2026-meta {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 1.5rem;
}

.vnncomp2026-meta-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.1rem;
    color: #4a5568;
}

.vnncomp2026-meta-item strong {
    color: #2d3748;
}

.vnncomp2026-links {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.vnncomp2026-link {
    color: #2563eb;
    text-decoration: none;
    padding: 0.5rem 1rem;
    border: 1px solid #2563eb;
    border-radius: 20px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.vnncomp2026-link:hover {
    background: #2563eb;
    color: white;
}

.vnncomp2026-section {
    margin-bottom: 3rem;
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
}

.vnncomp2026-section-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: #2d3748;
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #2563eb;
}

/* FLoC Olympic Games callout — gold accent to stand out among the white cards */
.olympics-callout {
    background: linear-gradient(135deg, #fffaf0 0%, #ffffff 65%);
    border-left: 5px solid #f6b73c;
}

.olympics-callout .vnncomp2026-section-title {
    border-bottom-color: #f6b73c;
}

.olympics-cta {
    margin-top: 1.25rem;
}

/* News Timeline */
.news-timeline {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.news-item {
    display: flex;
    gap: 1.5rem;
    align-items: flex-start;
    padding: 1rem;
    background: #f7fafc;
    border-radius: 10px;
    border-left: 4px solid #2563eb;
}

.news-date {
    font-weight: 600;
    color: #2563eb;
    white-space: nowrap;
    min-width: 120px;
}

.news-text {
    color: #4a5568;
}

/* Dates Grid */
.dates-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1rem;
}

.date-item {
    display: flex;
    flex-direction: column;
    padding: 1.25rem;
    background: #f7fafc;
    border-radius: 10px;
    border-left: 4px solid #cbd5e0;
}

.date-item.highlight {
    border-left-color: #2563eb;
    background: linear-gradient(135deg, #2563eb15 0%, #0d948815 100%);
}

.date-label {
    font-weight: 600;
    color: #2d3748;
    margin-bottom: 0.5rem;
}

.date-value {
    color: #4a5568;
}

.date-item.highlight .date-value {
    color: #2563eb;
    font-weight: 600;
}

/* Participation Grid */
.participation-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}

.participation-card {
    padding: 1.5rem;
    background: #f7fafc;
    border-radius: 10px;
    border-top: 4px solid #2563eb;
}

.participation-card h4 {
    font-size: 1.2rem;
    color: #2d3748;
    margin-bottom: 0.75rem;
}

.participation-card p {
    color: #4a5568;
    margin-bottom: 1rem;
    font-size: 0.95rem;
}

.participation-card ul {
    list-style: none;
    padding: 0;
}

.participation-card li {
    padding: 0.35rem 0;
    color: #4a5568;
    font-size: 0.9rem;
}

.participation-card li::before {
    content: "• ";
    color: #2563eb;
    font-weight: bold;
}

/* Committee Grid */
.committee-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}

.committee-role {
    text-align: center;
    padding: 2rem;
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
    border-radius: 15px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}

.committee-role h4 {
    font-size: 1rem;
    color: #2563eb;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.committee-role p {
    color: #4a5568;
    font-size: 0.95rem;
    line-height: 1.6;
}

/* Resources Grid */
.resources-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 1rem;
}

.resource-link {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 1.5rem 1rem;
    background: #f7fafc;
    border-radius: 10px;
    text-decoration: none;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.resource-link:hover {
    border-color: #2563eb;
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(37, 99, 235, 0.15);
}

.resource-icon {
    font-size: 2rem;
    margin-bottom: 0.75rem;
}

.resource-text {
    color: #4a5568;
    font-weight: 500;
    text-align: center;
    font-size: 0.95rem;
}

.resource-link:hover .resource-text {
    color: #2563eb;
}

.section-text {
    color: #4a5568;
    font-size: 1.05rem;
    line-height: 1.7;
}

/* Responsive adjustments for VNN-COMP 2026 */
@media (max-width: 768px) {
    .vnncomp2026-meta {
        flex-direction: column;
        align-items: center;
        gap: 0.75rem;
    }

    .news-item {
        flex-direction: column;
        gap: 0.5rem;
    }

    .news-date {
        min-width: auto;
    }

    .dates-grid,
    .participation-grid,
    .committee-grid,
    .resources-grid {
        grid-template-columns: 1fr;
    }
}

/* Sponsors Section */
.sponsors {
    padding: 6rem 0;
    background: linear-gradient(135deg, #ffffff 0%, #f5f7fa 100%);
}

.sponsors-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
    max-width: 1000px;
    margin: 0 auto;
}

.sponsor-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    background: white;
    padding: 2.5rem 2rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.08);
    border: 1px solid #edf2f7;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.sponsor-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 16px 40px rgba(37, 99, 235, 0.15);
}

.sponsor-logo-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 90px;
    margin-bottom: 1.5rem;
}

.sponsor-logo {
    max-height: 64px;
    max-width: 100%;
    width: auto;
    height: auto;
    object-fit: contain;
}

.sponsor-name {
    font-size: 1.15rem;
    font-weight: 600;
    color: #2d3748;
    margin-bottom: 0.75rem;
}

.sponsor-desc {
    color: #4a5568;
    font-size: 0.95rem;
    line-height: 1.65;
    margin-bottom: 1.25rem;
}

.sponsor-visit {
    margin-top: auto;
    color: #2563eb;
    text-decoration: none;
    font-weight: 600;
    font-size: 0.95rem;
    transition: color 0.2s ease;
}

.sponsor-visit:hover {
    color: #0d9488;
    text-decoration: underline;
}

.sponsors-cta {
    text-align: center;
    margin-top: 3rem;
    color: #4a5568;
    font-size: 1.05rem;
}

.sponsors-cta a {
    color: #2563eb;
    text-decoration: none;
    font-weight: 600;
}

.sponsors-cta a:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
    .sponsors-grid {
        grid-template-columns: 1fr;
    }
}

/* Competitions Section */
.competitions {
    padding: 6rem 0;
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
}

.timeline {
    max-width: 800px;
    margin: 0 auto;
    position: relative;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 3px;
    background: linear-gradient(to bottom, #2563eb, #0d9488);
    transform: translateX(-50%);
}

.timeline-item {
    position: relative;
    margin: 3rem 0;
    display: flex;
    align-items: center;
}

.timeline-item:nth-child(odd) {
    flex-direction: row-reverse;
}

.timeline-marker {
    width: 20px;
    height: 20px;
    background: #2563eb;
    border-radius: 50%;
    border: 4px solid white;
    box-shadow: 0 0 0 4px #2563eb;
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    z-index: 2;
}

.timeline-content {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    width: 45%;
    position: relative;
}

.timeline-item:nth-child(odd) .timeline-content {
    margin-right: 55%;
}

.timeline-item:nth-child(even) .timeline-content {
    margin-left: 55%;
}

.timeline-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: #2d3748;
    margin-bottom: 1rem;
}

.timeline-description {
    color: #4a5568;
    margin-bottom: 1.5rem;
}

.timeline-links {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.timeline-link {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border: 1px solid #2563eb;
    border-radius: 20px;
    transition: all 0.3s ease;
    font-size: 0.9rem;
}

.timeline-link:hover {
    background: #2563eb;
    color: white;
}

/* Repositories Section */
.repositories {
    padding: 6rem 0;
    background: white;
}

.repo-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.repo-card {
    transition: transform 0.3s ease;
}

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

.repo-year {
    font-size: 2rem;
    font-weight: 700;
    color: #2563eb;
    margin-bottom: 1.5rem;
}

.repo-links {
    display: grid;
    gap: 0.8rem;
}

.repo-link {
    color: #4a5568;
    text-decoration: none;
    padding: 0.8rem 1.5rem;
    background: #f7fafc;
    border-radius: 10px;
    transition: all 0.3s ease;
    font-weight: 500;
}

.repo-link:hover {
    background: #2563eb;
    color: white;
    transform: translateX(5px);
}

.repo-note {
    background: #fff3cd;
    border: 1px solid #ffeaa7;
    border-radius: 10px;
    padding: 1.5rem;
    text-align: center;
    color: #856404;
}

/* Contact Section */
.contact {
    padding: 6rem 0;
    background: linear-gradient(135deg, #2563eb 0%, #0d9488 100%);
    color: white;
}

.contact .section-title {
    color: white;
}

.contact-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 4rem;
    align-items: start;
}

.contact-info h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.contact-info p {
    margin-bottom: 2rem;
    opacity: 0.9;
}

.contact-list {
    list-style: none;
}

.contact-list li {
    padding: 0.5rem 0;
    opacity: 0.9;
}

.contact-list li::before {
    content: "✓ ";
    color: #a7f3d0;
    font-weight: bold;
}

.contact-links {
    display: grid;
    gap: 1rem;
}

.contact-btn {
    display: block;
    text-align: center;
    padding: 1rem 1.5rem;
    background: rgba(255,255,255,0.2);
    color: white;
    text-decoration: none;
    border-radius: 10px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.contact-btn:hover {
    background: white;
    color: #2563eb;
    transform: translateY(-2px);
}

/* Footer */
.footer {
    background: #2d3748;
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-info h3 {
    margin-bottom: 0.5rem;
    font-size: 1.3rem;
}

.footer-info p {
    opacity: 0.8;
}

.footer-links {
    display: flex;
    gap: 2rem;
    flex-wrap: wrap;
    justify-content: flex-end;
}

.footer-links a {
    color: white;
    text-decoration: none;
    opacity: 0.8;
    transition: opacity 0.3s ease;
}

.footer-links a:hover {
    opacity: 1;
}

.footer-bottom {
    border-top: 1px solid #4a5568;
    padding-top: 1rem;
    text-align: center;
    opacity: 0.6;
}

/* Participants Section */
.participants {
    padding: 6rem 0;
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
}

.participants-table-wrapper {
    overflow-x: auto;
    margin-top: 2rem;
}

.participants-table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
}

.participants-table th {
    background: linear-gradient(135deg, #2563eb 0%, #0d9488 100%);
    color: white;
    padding: 1rem;
    text-align: center;
    font-weight: 600;
    white-space: nowrap;
}

.participants-table th:first-child {
    text-align: left;
    min-width: 150px;
}

.participants-table td {
    padding: 0.75rem 1rem;
    border-bottom: 1px solid #e2e8f0;
    text-align: center;
}

.participants-table td:first-child {
    text-align: left;
    font-weight: 500;
}

.participants-table tr:last-child td {
    border-bottom: none;
}

.participants-table tr:hover {
    background-color: #f7fafc;
}

.participants-table .tool-link {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

.participants-table .tool-link:hover {
    color: #0d9488;
    text-decoration: underline;
}

.participants-table .checkmark {
    color: #2563eb;
    font-weight: bold;
    font-size: 1.2rem;
}

.participants-table .no-participation {
    color: #cbd5e0;
}

/* Tools List Inline Expansion */
.tools-list {
    display: none;
    margin-top: 1rem;
    padding: 1rem;
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
    border-radius: 10px;
    text-align: left;
}

.tools-list.expanded {
    display: block;
}

.tools-list-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 0.5rem;
}

.tools-list a {
    display: block;
    padding: 0.5rem 0.75rem;
    color: #4a5568;
    text-decoration: none;
    background: white;
    border-radius: 6px;
    font-size: 0.9rem;
    transition: all 0.2s ease;
    text-align: center;
}

.tools-list a:hover {
    background: #2563eb;
    color: white;
}

.tools-list span.tool-no-link {
    display: block;
    padding: 0.5rem 0.75rem;
    color: #718096;
    background: white;
    border-radius: 6px;
    font-size: 0.9rem;
    text-align: center;
}

.tools-toggle {
    cursor: pointer;
}

.tools-toggle .toggle-icon {
    font-size: 0.75rem;
    transition: transform 0.2s ease;
    display: inline-block;
}

.tools-toggle.active .toggle-icon {
    transform: rotate(180deg);
}

/* Report Link Styling */
.repo-link.report-link {
    background: linear-gradient(135deg, #2563eb15 0%, #0d948815 100%);
    border-left: 3px solid #2563eb;
}

.repo-link.report-link:hover {
    background: #2563eb;
    color: white;
    border-left: 3px solid #2563eb;
}

/* Publications Section */
.publications-section {
    margin-top: 3rem;
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
}

.publications-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: #2d3748;
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #2563eb;
}

.overview-paper {
    margin-bottom: 2rem;
    padding: 1.5rem;
    background: linear-gradient(135deg, #2563eb10 0%, #0d948810 100%);
    border-radius: 10px;
    border-left: 4px solid #2563eb;
}

.overview-paper h4 {
    font-size: 1.1rem;
    color: #2563eb;
    margin-bottom: 0.75rem;
}

.paper-citation {
    color: #4a5568;
    line-height: 1.7;
}

.paper-citation a {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
}

.paper-citation a:hover {
    text-decoration: underline;
}

.bibtex-section h4 {
    font-size: 1.1rem;
    color: #2d3748;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.copy-bibtex-btn {
    padding: 0.4rem 0.8rem;
    background: #2563eb;
    color: white;
    border: none;
    border-radius: 5px;
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.copy-bibtex-btn:hover {
    background: #0d9488;
    transform: translateY(-1px);
}

.copy-bibtex-btn.copied {
    background: #48bb78;
}

.bibtex-code {
    background: #2d3748;
    color: #e2e8f0;
    padding: 1.5rem;
    border-radius: 10px;
    overflow-x: auto;
    font-size: 0.85rem;
    line-height: 1.5;
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    max-height: 400px;
    overflow-y: auto;
}

/* Responsive Design */
@media (max-width: 768px) {
    .logo {
        font-size: 2.5rem;
    }
    
    .tagline {
        font-size: 1.1rem;
    }
    
    .nav-list {
        gap: 1rem;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-description {
        font-size: 1.1rem;
    }
    
    .about-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .timeline::before {
        left: 30px;
    }
    
    .timeline-item {
        flex-direction: column !important;
        align-items: flex-start;
    }
    
    .timeline-marker {
        left: 30px;
        transform: translateX(-50%);
    }
    
    .timeline-content {
        width: calc(100% - 80px);
        margin-left: 80px !important;
        margin-right: 0 !important;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .footer-links {
        justify-content: center;
    }
    
    .repo-grid {
        grid-template-columns: 1fr;
    }

    .participants-table {
        font-size: 0.9rem;
    }

    .participants-table th,
    .participants-table td {
        padding: 0.5rem;
    }

    .tools-list-grid {
        grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 4rem 0;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .timeline-content {
        padding: 1.5rem;
    }
    
    .timeline-links {
        flex-direction: column;
        gap: 0.5rem;
    }
}

/* ==========================================================================
   Accessibility & WCAG AA contrast
   ========================================================================== */

/* Skip-to-content link (visible on keyboard focus) */
.skip-link {
    position: absolute;
    top: 0.5rem;
    left: 50%;
    transform: translateX(-50%) translateY(-200%);
    z-index: 1000;
    background: #ffffff;
    color: var(--brand-link);
    padding: 0.75rem 1.25rem;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    box-shadow: 0 4px 14px rgba(0,0,0,0.18);
    transition: transform 0.2s ease;
}

.skip-link:focus {
    transform: translateX(-50%) translateY(0);
}

/* Visible keyboard focus indicator */
a:focus-visible,
button:focus-visible,
input:focus-visible {
    outline: 3px solid var(--brand-link);
    outline-offset: 2px;
    border-radius: 4px;
}

/* Darker brand purple for small / interactive text to meet AA (4.5:1 on white) */
.researcher-link,
.aaai2026-link,
.vnncomp2026-link,
.timeline-link,
.program-time,
.participants-table .tool-link,
.paper-citation a,
.overview-paper h4,
.committee-role h4,
.sponsors-cta a,
.sponsor-visit {
    color: var(--brand-link);
}

/* Bump borderline-grey body text to AA */
.program-topic-desc,
.tools-list span.tool-no-link {
    color: #5b6472;
}

.participants-table .no-participation {
    color: #64748b;
}

/* Pill / button hover and solid-fill controls: white text needs the darker fill for AA */
.aaai2026-link:hover,
.vnncomp2026-link:hover,
.timeline-link:hover,
.repo-link:hover {
    background: var(--brand-link);
    color: #ffffff;
}

.resource-link:hover .resource-text,
.speaker-link:hover {
    color: var(--brand-link);
}

.copy-bibtex-btn {
    background: var(--brand-link);
}

.copy-bibtex-btn:hover {
    background: var(--brand-dark);
}

/* Tools expand/collapse is now a real <button>; reset native button chrome to match .repo-link */
button.tools-toggle {
    font-family: inherit;
    font-size: 1rem;
    font-weight: 500;
    width: 100%;
    border: none;
    cursor: pointer;
    color: #4a5568;
}

/* Disabled (no-target) repository links rendered as muted, non-interactive spans */
.repo-link.disabled {
    color: #64748b;
    background: #f7fafc;
    cursor: default;
}

.repo-link.disabled:hover {
    background: #f7fafc;
    color: #64748b;
    transform: none;
}

/* Respect users who prefer reduced motion */
@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }

    .btn:hover,
    .repo-card:hover,
    .sponsor-card:hover,
    .resource-link:hover,
    .nav-list a:hover,
    .contact-btn:hover,
    .timeline-link:hover {
        transform: none !important;
    }
}

/* ---- ARCH-COMP additions ---- */
/* Header logo lockup: white ARCH mark + wordmark on the gradient */
.logo {
    display: inline-block;
    text-decoration: none;
    color: #ffffff;
}
.logo-img {
    height: 82px;
    width: auto;
    display: block;
    margin: 0 auto 0.55rem;
}
.logo-word {
    display: block;
    font-size: 1.6rem;
    font-weight: 700;
    letter-spacing: 0.08em;
}
/* Category lead line inside category cards */
.cat-lead {
    margin-top: 0.85rem;
    font-size: 0.9rem;
    color: #64748b;
}
.cat-lead strong { color: var(--brand-slate); }

@media (max-width: 600px) {
    .logo-img { height: 60px; }
    .logo-word { font-size: 1.3rem; }
}

/* ---- Subpages (participate / proceedings) ---- */
.subpage { padding: 3.5rem 0 5rem; background: #fff; }
.subpage .container { max-width: 980px; }
.breadcrumb { margin-bottom: 1.25rem; font-size: 0.95rem; color: #94a3b8; }
.breadcrumb a { color: var(--brand-link); text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }
.subpage-title { font-size: 2.4rem; font-weight: 700; color: #2d3748; margin-bottom: 0.6rem; }
.subpage-lead { font-size: 1.15rem; color: #4a5568; margin-bottom: 2.5rem; max-width: 780px; }
.subpage h2 { font-size: 1.6rem; color: #2d3748; margin: 2.5rem 0 1.25rem; padding-bottom: 0.4rem; border-bottom: 2px solid var(--brand); }

/* Key-facts strip */
.facts { display: flex; flex-wrap: wrap; gap: 0.75rem 2rem; padding: 1.25rem 1.5rem;
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%); border-radius: 12px; margin-bottom: 2rem; }
.facts div { font-size: 1rem; color: #4a5568; }
.facts strong { color: var(--brand-slate); }

/* Numbered steps */
.step-list { display: grid; gap: 1.1rem; }
.step { display: grid; grid-template-columns: 48px 1fr; gap: 1.25rem; padding: 1.4rem 1.5rem;
    border: 1px solid #e5e7eb; border-radius: 14px; background: #fff; box-shadow: 0 1px 3px rgba(16,24,40,0.05); }
.step-num { width: 44px; height: 44px; border-radius: 50%; display: flex; align-items: center;
    justify-content: center; font-weight: 700; color: #fff; font-size: 1.2rem;
    background: linear-gradient(135deg, #2563eb 0%, #0d9488 100%); }
.step-body h3 { font-size: 1.2rem; color: #2d3748; margin-bottom: 0.4rem; }
.step-deadline { display: inline-block; font-size: 0.8rem; font-weight: 600; color: #0d7a6e;
    background: #e6f4f1; padding: 0.15rem 0.7rem; border-radius: 999px; margin-bottom: 0.6rem; }
.step-body p { color: #4a5568; }
.step-body a { color: var(--brand-link); }

/* Editions table */
.table-wrap { overflow-x: auto; border-radius: 10px; box-shadow: 0 4px 15px rgba(0,0,0,0.08); }
.editions-table { width: 100%; border-collapse: collapse; background: #fff; min-width: 640px; }
.editions-table th { background: linear-gradient(135deg, #2563eb 0%, #0d9488 100%); color: #fff;
    padding: 0.9rem 1rem; text-align: left; font-weight: 600; }
.editions-table td { padding: 0.8rem 1rem; border-bottom: 1px solid #eef0f3; vertical-align: top; }
.editions-table tr:last-child td { border-bottom: none; }
.editions-table tbody tr:hover { background: #f7fafc; }
.editions-table a { color: var(--brand-link); text-decoration: none; font-weight: 500; }
.editions-table a:hover { text-decoration: underline; }
.editions-table .muted { color: #94a3b8; }
.year-cell { font-weight: 700; color: #2d3748; white-space: nowrap; }

/* Workshop hub: resource cards carry a one-line description under the label */
.resource-link .resource-title { font-weight: 600; color: #2d3748; margin-bottom: 0.3rem; }
.resource-link:hover .resource-title { color: var(--brand-link); }
.resource-desc { font-size: 0.85rem; color: #5b6472; font-weight: 400; text-align: center; line-height: 1.45; }

/* Organizers sits directly below the (white) categories cards — keep it white too */
#organizers.participants { background: #ffffff; }

/* Center a lone category card left over on the last row (7 cards -> 3+3+1) */
@media (min-width: 964px) {
    #categories .repo-card:last-child:nth-child(3n+1) {
        grid-column: 1 / -1;
        justify-self: center;
        width: calc((100% - 4rem) / 3);
    }
}
@media (min-width: 768px) and (max-width: 963px) {
    #categories .repo-card:last-child:nth-child(2n+1) {
        grid-column: 1 / -1;
        justify-self: center;
        width: calc((100% - 2rem) / 2);
    }
}

/* Editions page: year selector + per-year sections */
.year-picker { display: flex; align-items: center; gap: 0.75rem; flex-wrap: wrap;
    position: sticky; top: 0; z-index: 5; padding: 1rem 0; margin-bottom: 1.5rem;
    background: rgba(255,255,255,0.92); backdrop-filter: blur(6px); border-bottom: 1px solid #eef0f3; }
.year-picker label { font-weight: 600; color: #2d3748; }
.year-select { font-family: inherit; font-size: 1.05rem; font-weight: 600; color: var(--brand-link);
    padding: 0.55rem 2.4rem 0.55rem 1rem; border: 2px solid var(--brand); border-radius: 999px;
    background: #fff url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'><path d='M1 1l5 5 5-5' fill='none' stroke='%232563eb' stroke-width='2'/></svg>") no-repeat right 1rem center;
    -webkit-appearance: none; appearance: none; cursor: pointer; }
.year-select:hover { background-color: #f7fafc; }
.edition-head { margin-bottom: 1.5rem; }
.edition-head .subpage-title { margin-bottom: 0.3rem; }
.edition-when { color: #64748b; font-size: 1.05rem; font-weight: 500; }
.edition-badge { font-size: 0.7rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.04em;
    vertical-align: middle; color: #fff; background: var(--brand); padding: 0.2rem 0.6rem; border-radius: 999px; }
.edition-badge.muted-badge { background: #94a3b8; }
.edition[hidden] { display: none; }

/* File listings (benchmarks / tool presentations / experience reports) */
.file-year { margin: 2.25rem 0 1rem; font-size: 1.35rem; font-weight: 700; color: var(--brand); }
.file-list { list-style: none; padding: 0; display: grid; gap: 0.6rem; }
.file-item { display: flex; align-items: baseline; gap: 0.75rem; padding: 0.9rem 1.1rem;
    border: 1px solid #e5e7eb; border-radius: 12px; background: #fff; box-shadow: 0 1px 3px rgba(16,24,40,0.04); }
.file-item:hover { border-color: var(--brand); box-shadow: 0 4px 14px rgba(37,99,235,0.08); }
.file-title { font-weight: 500; color: #2d3748; flex: 1; }
.file-links { display: flex; flex-wrap: wrap; gap: 0.4rem 0.75rem; white-space: nowrap; }
.file-links a { color: var(--brand-link); text-decoration: none; font-weight: 600; font-size: 0.9rem; }
.file-links a:hover { text-decoration: underline; }
.file-meta { color: #94a3b8; font-size: 0.8rem; font-weight: 400; }

/* Navbar: visually separate in-page section links from standalone pages */
.nav-list .nav-sep { width: 1px; height: 22px; align-self: center; background: rgba(255,255,255,0.45); }
.about-cta { margin-top: 1.75rem; display: flex; gap: 1rem; flex-wrap: wrap; }
@media (max-width: 600px) { .nav-list .nav-sep { display: none; } }