:root {
    --text: #1a1a1a;
    --muted: #666;
    --soft: #586069;
    --accent: #508af6;
    --accent-soft: #f0f4f8;
    --border: #e5e5e5;
    --bg: #ffffff;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: "Source Serif 4", "Source Serif Pro", Charter, Georgia, "Times New Roman", serif;
    font-size: 17px;
    line-height: 1.7;
    color: var(--text);
    background-color: var(--bg);
    margin: 0;
    padding: 0;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ------------ Header ------------ */
.header-wrapper {
    background-color: #ffffff;
    border-bottom: 1px solid var(--border);
    padding: 64px 20px 48px;
}
.central-header {
    max-width: 1100px;
    margin: 0 auto;
    text-align: center;
    font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}
.title-section h1 {
    font-size: 2.5rem;
    font-weight: 800;
    line-height: 1.2;
    letter-spacing: -0.02em;
    margin: 0 0 8px;
    color: var(--text);
}
.title-section h2 {
    font-size: 1.6rem;
    font-weight: 600;
    line-height: 1.3;
    margin: 0;
    color: var(--text);
}
.title-section em {
    font-style: italic;
    color: var(--accent);
}

.authors {
    margin-top: 28px;
    font-size: 1.05rem;
    color: var(--text);
}
.authors a {
    color: var(--accent);
    border-bottom: 1px solid transparent;
    transition: border-color 0.15s ease;
}
.authors a:hover {
    border-bottom-color: var(--accent);
    text-decoration: none;
}
.authors sup { font-size: 0.7em; color: var(--muted); }
.affiliations {
    margin-top: 8px;
    color: var(--muted);
    font-size: 0.95rem;
}

/* ------------ Buttons ------------ */
.button-row {
    margin-top: 32px;
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 10px;
}
.button {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 9px 18px;
    border-radius: 999px;
    background-color: var(--text);
    color: #fff;
    border: none;
    font-family: Inter, sans-serif;
    font-size: 0.92rem;
    font-weight: 500;
    text-decoration: none;
    transition: transform 0.12s ease, background-color 0.15s ease;
}
.button:hover { background-color: #000; transform: translateY(-1px); text-decoration: none; }
.button.disabled {
    background-color: #c8c8c8;
    color: #fff;
    cursor: not-allowed;
    pointer-events: none;
}
.button .icon { display: inline-flex; align-items: center; }

/* ------------ TL;DR ------------ */
.tldr {
    max-width: 780px;
    margin: 36px auto 0;
    background-color: #f8f9fa;
    border-left: 4px solid var(--accent);
    padding: 18px 22px;
    border-radius: 0;
    text-align: left;
    font-family: "Source Serif 4", Charter, Georgia, serif;
    font-size: 1.02rem;
    line-height: 1.6;
    color: var(--text);
}
.tldr .label {
    font-family: Inter, sans-serif;
    font-weight: 700;
    color: var(--text);
    margin-right: 4px;
}
.tldr em {
    font-style: italic;
    color: inherit;
}
.tldr strong {
    color: var(--accent);
    font-weight: 700;
}

/* ------------ Article ------------ */
.article {
    max-width: 780px;
    margin: 0 auto;
    padding: 56px 20px;
}
.section { margin-bottom: 56px; }
.section h3 {
    font-family: Inter, sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0 0 18px;
    text-align: center;
    letter-spacing: -0.01em;
}
.section p {
    text-align: justify;
    margin: 0 0 14px;
}
.section p:last-child { margin-bottom: 0; }

/* ------------ Teaser figure ------------ */
.teaser {
    max-width: 1040px;
    margin: 56px auto 0;
    padding: 0 20px;
}
.teaser img {
    width: 100%;
    height: auto;
    display: block;
    border-radius: 6px;
}
.teaser figcaption {
    margin-top: 14px;
    font-size: 0.95rem;
    color: var(--soft);
    text-align: justify;
    line-height: 1.55;
}
.teaser figcaption .label {
    font-weight: 700;
    color: var(--text);
}

/* ------------ Key Contributions ------------ */
.key-findings {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
    margin-top: 8px;
}
.key-finding {
    display: flex;
    gap: 16px;
    padding: 18px 20px;
    border: 1px solid var(--border);
    border-radius: 8px;
    background-color: #fafbfc;
}
.key-finding-number {
    flex-shrink: 0;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background-color: var(--accent);
    color: #fff;
    font-family: Inter, sans-serif;
    font-weight: 700;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 0.95rem;
}
.key-finding p {
    margin: 0;
    text-align: left;
    line-height: 1.6;
    font-size: 1rem;
}
.key-finding p strong {
    color: var(--text);
}

/* ------------ Demos ------------ */
.demos-section {
    max-width: 1180px;
    margin: 0 auto;
    padding: 0 20px 56px;
}
.demos-section > h3 {
    font-family: Inter, sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0 0 8px;
    text-align: center;
    letter-spacing: -0.01em;
}
.demos-section > .section-intro {
    text-align: center;
    color: var(--soft);
    margin: 0 0 28px;
    font-size: 0.98rem;
}
.demos-group {
    margin-bottom: 56px;
}
.demos-group:last-child { margin-bottom: 0; }
.demos-group > h4 {
    font-family: Inter, sans-serif;
    font-size: 1.25rem;
    font-weight: 700;
    margin: 0 0 6px;
    padding-bottom: 8px;
    border-bottom: 2px solid var(--text);
    text-align: left;
    letter-spacing: -0.01em;
}
.demos-group > .group-desc {
    margin: 10px 0 20px;
    color: var(--soft);
    font-size: 0.95rem;
    text-align: left;
    line-height: 1.55;
}

.demo-block {
    margin-top: 36px;
}
.demo-block:first-of-type { margin-top: 8px; }

.demo-block h4 {
    font-family: Inter, sans-serif;
    font-size: 1.15rem;
    font-weight: 700;
    margin: 0 0 6px;
    text-align: left;
}
.demo-block .demo-desc {
    margin: 0 0 16px;
    color: var(--soft);
    font-size: 0.95rem;
    text-align: left;
}
.demo-block .prompt {
    background-color: #fafbfc;
    border: 1px solid var(--border);
    border-left: 3px solid var(--accent);
    border-radius: 6px;
    padding: 10px 14px;
    margin: 0 0 14px;
    font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
    font-size: 0.92rem;
    color: #2b3340;
    text-align: left;
    word-break: break-word;
}
.demo-block .prompt .prompt-label {
    font-family: Inter, sans-serif;
    font-weight: 700;
    color: var(--accent);
    margin-right: 6px;
}

/* ----- Timing condition (mini gantt) ----- */
.timing {
    background-color: #fafbfc;
    border: 1px solid var(--border);
    border-left: 3px solid var(--accent);
    border-radius: 6px;
    padding: 12px 14px 10px;
    margin: 0 0 16px;
    font-family: Inter, sans-serif;
    text-align: left;
}
.timing .timing-label {
    font-weight: 700;
    color: var(--accent);
    font-size: 0.92rem;
    margin-bottom: 10px;
}
.timing-events {
    display: grid;
    grid-template-columns: 220px 1fr;
    column-gap: 14px;
    row-gap: 8px;
    align-items: center;
}
.timing-event-name {
    font-size: 0.88rem;
    color: #2b3340;
    text-align: right;
    line-height: 1.3;
    font-weight: 500;
}
.timing-event-track {
    position: relative;
    height: 20px;
    background-color: #eef2f7;
    border-radius: 4px;
    overflow: hidden;
}
.timing-event-bar {
    position: absolute;
    top: 0;
    bottom: 0;
    background-color: var(--bar-color, var(--accent));
    border-radius: 3px;
    box-shadow: inset 0 0 0 1px rgba(0,0,0,0.04);
}
.timing-axis {
    display: grid;
    grid-template-columns: 220px 1fr;
    column-gap: 14px;
    margin-top: 6px;
}
.timing-axis-marks {
    grid-column: 2;
    display: flex;
    justify-content: space-between;
    font-size: 0.74rem;
    color: var(--muted);
    font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}
.timing-intervals {
    margin-top: 8px;
    font-size: 0.78rem;
    color: var(--muted);
    font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
    line-height: 1.5;
    word-break: break-word;
}
.timing-intervals .ti-name { color: #2b3340; }
.timing-intervals .ti-sep { color: #cbd2da; margin: 0 6px; }

@media (max-width: 720px) {
    .timing-events,
    .timing-axis { grid-template-columns: 130px 1fr; }
    .timing-event-name { font-size: 0.82rem; }
}

.demo-table-wrapper {
    overflow-x: auto;
    border: 1px solid var(--border);
    border-radius: 8px;
    background-color: #fff;
}
.demo-table {
    width: auto;
    border-collapse: collapse;
    font-family: Inter, sans-serif;
    font-size: 0.92rem;
}
.demo-table th,
.demo-table td {
    padding: 10px 12px;
    border-bottom: 1px solid var(--border);
    border-right: 1px solid var(--border);
    text-align: center;
    vertical-align: middle;
    background-color: #fff;
}
.demo-table th:last-child,
.demo-table td:last-child { border-right: none; }
.demo-table tr:last-child td { border-bottom: none; }
.demo-table thead th {
    background-color: #fafbfc;
    font-weight: 600;
    color: var(--text);
    white-space: nowrap;
}
.demo-table thead th.col-ours { color: var(--accent); }
.demo-table tbody th {
    background-color: #fafbfc;
    font-weight: 600;
    text-align: left;
    white-space: nowrap;
    color: var(--soft);
    width: 70px;
}
.demo-table .mel {
    padding: 8px;
    width: 210px;
}
.demo-table .mel img {
    display: block;
    width: 210px;
    height: 120px;
    object-fit: fill;
    margin: 0 auto;
    border-radius: 4px;
    background-color: #f0f0f0;
}
.demo-table .audio {
    padding: 8px;
    width: 210px;
}
.demo-table .audio audio {
    display: block;
    width: 210px;
    height: 32px;
    margin: 0 auto;
}
.demo-table td.col-ours {
    background-color: #f4f8ff;
}

.demo-table.full-width {
    width: 100%;
}
.demo-table.full-width .mel,
.demo-table.full-width .audio {
    width: auto;
}
.demo-table.full-width .mel img {
    width: 100%;
    height: 130px;
}
.demo-table.full-width .audio audio {
    width: 100%;
}

@media (max-width: 720px) {
    .demo-table .mel,
    .demo-table .audio { width: 180px; }
    .demo-table .mel img,
    .demo-table .audio audio { width: 180px; }
    .demo-table .mel img { height: 70px; }
    .demo-table th,
    .demo-table td { padding: 6px; font-size: 0.86rem; }
    .demo-table tbody th { width: 56px; }
}

/* ------------ Footer ------------ */
footer {
    border-top: 1px solid var(--border);
    padding: 28px 20px;
    text-align: center;
    color: var(--muted);
    font-family: Inter, sans-serif;
    font-size: 0.85rem;
}

/* ------------ Responsive ------------ */
@media (max-width: 640px) {
    .header-wrapper { padding: 40px 16px 32px; }
    .title-section h1 { font-size: 1.85rem; }
    .title-section h2 { font-size: 1.2rem; }
    .article { padding: 40px 16px; }
    .button { font-size: 0.86rem; padding: 8px 14px; }
}