/* ThinkProprio Project Website Styles */
/* Inspired by Diffusion Policy (diffusion-policy.cs.columbia.edu) */

/* ========== Variables ========== */
:root {
    --primary-color: #2c3e50;
    --accent-color: #3498db;
    --accent-hover: #2980b9;
    --success-color: #27ae60;
    --bg-light: #f8f9fa;
    --bg-white: #ffffff;
    --text-dark: #333333;
    --text-muted: #666666;
    --border-color: #e0e0e0;
    --max-width: 1100px;
    --section-padding: 4rem 0;
    --card-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
    --card-radius: 8px;
}

/* ========== Reset & Base ========== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Source Sans 3', 'Helvetica Neue', Arial, sans-serif;
    font-size: 16px;
    line-height: 1.7;
    color: var(--text-dark);
    background: var(--bg-white);
}

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

/* ========== Typography ========== */
h1, h2, h3, h4 {
    font-weight: 600;
    line-height: 1.3;
}

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

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

code, pre {
    font-family: 'Source Code Pro', 'Consolas', monospace;
}

/* ========== Header ========== */
.header {
    text-align: center;
    padding: 3rem 0 2rem;
    background: var(--bg-white);
}

.logos {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 2rem;
    margin-bottom: 2rem;
}

.logo {
    height: 50px;
    width: auto;
    opacity: 0.8;
}

.title {
    font-size: 2.8rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.subtitle {
    font-size: 1.5rem;
    font-weight: 400;
    color: var(--text-muted);
    margin-bottom: 1.5rem;
}

.authors {
    margin-bottom: 0.5rem;
}

.author {
    display: inline-block;
    margin: 0 0.5rem;
    font-size: 1.1rem;
}

.author sup {
    font-size: 0.7em;
    color: var(--accent-color);
}

.affiliations {
    margin-bottom: 1rem;
    color: var(--text-muted);
    font-size: 0.95rem;
}

.affiliation {
    display: inline-block;
    margin: 0 0.75rem;
}

.affiliation sup {
    font-size: 0.8em;
    color: var(--accent-color);
}

.venue {
    font-size: 1rem;
    color: var(--text-muted);
    font-style: italic;
    margin-bottom: 1.5rem;
}

/* ========== Buttons ========== */
.links {
    display: flex;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: 6px;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.2s ease;
}

.btn-paper {
    background: #c0392b;
    color: white;
}

.btn-paper:hover {
    background: #a93226;
    color: white;
}

.btn-code {
    background: #333;
    color: white;
}

.btn-code:hover {
    background: #1a1a1a;
    color: white;
}

.btn-model {
    background: var(--accent-color);
    color: white;
}

.btn-model:hover {
    background: var(--accent-hover);
    color: white;
}

/* ========== Teaser ========== */
.teaser {
    padding: 2rem 0 3rem;
    background: var(--bg-white);
}

.teaser-image {
    width: 100%;
    display: block;
    margin: 0 auto 1.5rem;
    border-radius: var(--card-radius);
}

.teaser-caption {
    text-align: center;
    color: var(--text-muted);
    font-size: 1.05rem;
    max-width: 800px;
    margin: 0 auto;
}

/* ========== Section Titles ========== */
.section-title {
    font-size: 1.8rem;
    text-align: center;
    margin-bottom: 2rem;
    color: var(--primary-color);
}

.section-description {
    text-align: center;
    color: var(--text-muted);
    margin-bottom: 2rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

/* ========== Highlights ========== */
.highlights {
    padding: var(--section-padding);
    background: var(--bg-light);
}

.highlight-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.5rem;
}

.highlight-card {
    background: var(--bg-white);
    border-radius: var(--card-radius);
    padding: 1.5rem;
    text-align: center;
    box-shadow: var(--card-shadow);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.highlight-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.12);
}

.highlight-image {
    height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1rem;
    color: var(--accent-color);
}

.highlight-image img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

.highlight-card h4 {
    font-size: 1.1rem;
    margin-bottom: 0.75rem;
    color: var(--primary-color);
}

.highlight-card p {
    font-size: 0.95rem;
    color: var(--text-muted);
    line-height: 1.5;
}

/* ========== Metrics ========== */
.metrics {
    padding: var(--section-padding);
    background: var(--primary-color);
    color: white;
}

.metrics-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
    text-align: center;
}

.metric-card {
    display: flex;
    flex-direction: column;
}

.metric-number {
    font-size: 3.5rem;
    font-weight: 700;
    color: white;
    line-height: 1;
    margin-bottom: 0.5rem;
}

.metric-label {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.metric-context {
    font-size: 0.9rem;
    opacity: 0.8;
}

/* ========== Method ========== */
.method {
    padding: var(--section-padding);
    background: var(--bg-white);
}

.method-image {
    width: 100%;
    max-width: 950px;
    display: block;
    margin: 0 auto 2rem;
    border-radius: var(--card-radius);
}

.method-description {
    max-width: 800px;
    margin: 0 auto;
}

.method-description p {
    margin-bottom: 1rem;
    text-align: justify;
}

/* ========== Results ========== */
.results {
    padding: var(--section-padding);
    background: var(--bg-light);
}

.table-title {
    font-size: 1.2rem;
    text-align: center;
    margin: 2rem 0 1rem;
    color: var(--primary-color);
}

.table-title:first-of-type {
    margin-top: 0;
}

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

.results-table {
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
    border-collapse: collapse;
    background: var(--bg-white);
    border-radius: var(--card-radius);
    overflow: hidden;
    box-shadow: var(--card-shadow);
}

.results-table th,
.results-table td {
    padding: 0.75rem 1rem;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
}

.results-table th {
    background: var(--primary-color);
    color: white;
    font-weight: 600;
    font-size: 0.95rem;
}

.results-table th:first-child,
.results-table td:first-child {
    text-align: left;
}

.results-table tbody tr:hover {
    background: rgba(52, 152, 219, 0.05);
}

.results-table .highlight-row {
    background: rgba(39, 174, 96, 0.1);
}

.results-table .highlight-row:hover {
    background: rgba(39, 174, 96, 0.15);
}

/* ========== Videos ========== */
.videos {
    padding: var(--section-padding);
    background: var(--bg-white);
}

/* Trajectory Container */
.trajectory-container {
    margin-bottom: 3rem;
}

.trajectory-container:last-child {
    margin-bottom: 0;
}

.trajectory-title {
    font-size: 1.3rem;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
    text-align: center;
}

/* Timeline */
.timeline {
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    padding: 0 1rem;
}

.timeline-step {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: var(--border-color);
    color: var(--text-muted);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 0.9rem;
    transition: all 0.3s ease;
}

.timeline-step.active {
    background: var(--accent-color);
    color: white;
}

.timeline-connector {
    width: 40px;
    height: 3px;
    background: var(--border-color);
    transition: background 0.3s ease;
}

.timeline-connector.active {
    background: var(--accent-color);
}

/* Video Carousel */
.video-carousel {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.carousel-btn {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    border: 2px solid var(--border-color);
    background: var(--bg-white);
    color: var(--text-dark);
    font-size: 1.5rem;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.carousel-btn:hover:not(:disabled) {
    background: var(--accent-color);
    border-color: var(--accent-color);
    color: white;
}

.carousel-btn:disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

.carousel-viewport {
    flex: 1;
    overflow: hidden;
}

.carousel-track {
    display: flex;
    gap: 1.5rem;
    transition: transform 0.4s ease;
}

.video-card {
    flex: 0 0 calc(50% - 0.75rem);
    background: var(--bg-light);
    border-radius: var(--card-radius);
    overflow: hidden;
    box-shadow: var(--card-shadow);
}

.video-card video {
    width: 100%;
    display: block;
}

.video-caption {
    padding: 0.75rem 1rem;
    font-size: 0.9rem;
    color: var(--text-muted);
    text-align: center;
    background: var(--bg-white);
    border-top: 1px solid var(--border-color);
}

/* Responsive carousel */
@media (min-width: 900px) {
    .video-card {
        flex: 0 0 calc(33.333% - 1rem);
    }
}

@media (max-width: 600px) {
    .video-card {
        flex: 0 0 100%;
    }

    .carousel-btn {
        width: 40px;
        height: 40px;
        font-size: 1.2rem;
    }

    .timeline-step {
        width: 28px;
        height: 28px;
        font-size: 0.8rem;
    }

    .timeline-connector {
        width: 24px;
    }
}

/* Legacy video grid (used by VideoGrid class in main.js) */
.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}

.video-card .video-title {
    padding: 0.75rem 1rem;
    font-size: 0.9rem;
    color: var(--text-muted);
    text-align: center;
}

/* ========== Visualization ========== */
.visualization {
    padding: var(--section-padding);
    background: var(--bg-light);
}

.viz-image {
    width: 100%;
    max-width: 1000px;
    display: block;
    margin: 0 auto 1.5rem;
    border-radius: var(--card-radius);
    box-shadow: var(--card-shadow);
}

.viz-caption {
    text-align: center;
    color: var(--text-muted);
    max-width: 800px;
    margin: 0 auto;
}

/* ========== Citation ========== */
.citation {
    padding: var(--section-padding);
    background: var(--bg-white);
}

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

.bibtex {
    background: var(--bg-light);
    padding: 1.5rem;
    border-radius: var(--card-radius);
    overflow-x: auto;
    font-size: 0.9rem;
    line-height: 1.5;
}

.copy-btn {
    position: absolute;
    top: 0.75rem;
    right: 0.75rem;
    background: var(--accent-color);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.85rem;
    transition: background 0.2s ease;
}

.copy-btn:hover {
    background: var(--accent-hover);
}

.copy-btn.copied {
    background: var(--success-color);
}

/* ========== Acknowledgements ========== */
.acknowledgements {
    padding: 3rem 0;
    background: var(--bg-light);
    text-align: center;
}

.acknowledgements p {
    margin-bottom: 0.5rem;
    color: var(--text-muted);
}

.template-credit {
    font-size: 0.9rem;
    margin-top: 1rem;
}

/* ========== Footer ========== */
.footer {
    padding: 1.5rem 0;
    background: var(--primary-color);
    color: white;
    text-align: center;
    font-size: 0.9rem;
}

/* ========== Responsive ========== */
@media (max-width: 992px) {
    .highlight-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .metrics-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }

    .metric-number {
        font-size: 2.5rem;
    }
}

@media (max-width: 768px) {
    .title {
        font-size: 2rem;
    }

    .subtitle {
        font-size: 1.2rem;
    }

    .author {
        display: block;
        margin: 0.25rem 0;
    }

    .affiliation {
        display: block;
        margin: 0.25rem 0;
    }

    .links {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        max-width: 200px;
        justify-content: center;
    }

    .section-title {
        font-size: 1.5rem;
    }
}

@media (max-width: 576px) {
    .highlight-grid {
        grid-template-columns: 1fr;
    }

    .metrics-grid {
        grid-template-columns: 1fr;
    }

    .metric-card {
        padding: 1rem 0;
        border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    }

    .metric-card:last-child {
        border-bottom: none;
    }

    .results-table {
        font-size: 0.85rem;
    }

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