:root {
    --blue: #1a73e8;
    --blue-dark: #185abc;
    --green: #0f766e;
    --amber: #b45309;
    --ink: #202124;
    --text: #3c4043;
    --muted: #5f6368;
    --line: #e1e5ea;
    --panel: #f8f9fa;
    --panel-strong: #eef3f8;
}

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

html {
    scroll-behavior: smooth;
}

body {
    max-width: 1200px;
    margin: 40px auto;
    padding: 0 40px;
    background: #fff;
    color: var(--text);
    font-family: 'Google Sans', Arial, sans-serif;
    line-height: 1.6;
}

a {
    color: var(--blue);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

.hero {
    text-align: center;
}

.eyebrow {
    margin-bottom: 12px;
    color: var(--green);
    font-size: 0.92rem;
    font-weight: 700;
    letter-spacing: 0;
    text-transform: uppercase;
}

h1,
h2 {
    color: var(--ink);
    font-weight: 500;
    line-height: 1.2;
    letter-spacing: 0;
}

h1 {
    margin-bottom: 24px;
    font-size: 2.72rem;
}

h2 {
    margin-bottom: 26px;
    text-align: center;
    font-size: 1.92rem;
}

.authors {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 4px 12px;
    margin-bottom: 10px;
    color: var(--text);
    font-size: 1rem;
}

.authors span {
    white-space: nowrap;
}

.affiliations {
    max-width: 980px;
    margin: 0 auto 30px;
    color: var(--muted);
    font-size: 0.92rem;
}

sup {
    line-height: 0;
    font-size: 75%;
}

.links {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    gap: 16px;
    margin-bottom: 36px;
}

.links a,
.copy-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    min-width: 112px;
    height: 46px;
    padding: 10px 20px;
    border: 0;
    border-radius: 8px;
    background: var(--blue);
    color: #fff;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    font: inherit;
    font-weight: 500;
    line-height: 1;
    cursor: pointer;
    transition: background-color 0.2s, box-shadow 0.2s, transform 0.2s;
}

.links a:hover,
.copy-button:hover {
    background: var(--blue-dark);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.18);
    text-decoration: none;
    transform: translateY(-1px);
}

.links svg {
    flex: 0 0 auto;
}

.chapters {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 5px;
    max-width: 1040px;
    margin: -4px auto 28px;
    padding: 0;
}

.chapters button {
    flex: 1 1 120px;
    min-height: 38px;
    padding: 5px 10px;
    border: 3px solid transparent;
    border-radius: 6px;
    background: var(--blue);
    color: #fff;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    font: inherit;
    font-size: 0.86rem;
    font-weight: 500;
    line-height: 1.2;
    cursor: pointer;
    transition: background-color 0.2s, border-color 0.2s, color 0.2s, box-shadow 0.2s;
}

.chapters button:hover:not(.selected) {
    background: var(--blue-dark);
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.18);
}

.chapters button.selected {
    border-color: var(--blue);
    background: #fff;
    color: var(--blue);
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.18);
}

.section {
    margin-bottom: 30px;
    padding: 30px;
    border: 1px solid var(--line);
    border-radius: 18px;
    background: var(--panel);
}

.overview-section {
    padding-top: 34px;
}

.overview-figure {
    margin-bottom: 18px;
}

.teaser-figure img {
    aspect-ratio: 2481 / 697;
    object-fit: contain;
}

.section p {
    max-width: 980px;
    margin: 0 auto 24px;
    color: var(--text);
    font-size: 1.04rem;
}

.figure-wrap {
    margin: 0 auto 24px;
    padding: 20px;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: #fff;
    text-align: center;
}

.figure-wrap:last-child {
    margin-bottom: 0;
}

.figure-wrap img {
    display: block;
    width: 100%;
    max-height: 820px;
    object-fit: contain;
}

.figure-wrap.compact img {
    max-height: 430px;
}

figcaption {
    margin-top: 12px;
    color: var(--muted);
    font-size: 0.92rem;
    line-height: 1.45;
}

.summary-grid,
.stage-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
    margin-top: 8px;
}

.summary-grid div,
.stage-grid div {
    min-height: 132px;
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: #fff;
}

.summary-grid strong {
    display: block;
    margin-bottom: 8px;
    color: var(--blue);
    font-size: 2rem;
    line-height: 1;
}

.summary-grid span,
.stage-grid span {
    display: block;
    color: var(--muted);
    font-size: 0.94rem;
}

.stage-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    margin-bottom: 24px;
}

.stage-grid div:nth-child(1) strong {
    color: var(--blue);
}

.stage-grid div:nth-child(2) strong {
    color: var(--green);
}

.stage-grid div:nth-child(3) strong {
    color: var(--amber);
}

.stage-grid div:nth-child(4) strong {
    color: #7c3aed;
}

.stage-grid strong {
    display: block;
    margin-bottom: 8px;
    color: var(--ink);
    line-height: 1.25;
}

.probe-grid {
    display: grid;
    grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.4fr);
    gap: 16px;
}

.kb-embed {
    height: 660px;
    border: 1px solid var(--line);
    border-radius: 12px;
    overflow: hidden;
    background: #fff;
}

.kb-embed iframe {
    display: block;
    width: 100%;
    height: 100%;
    border: 0;
}

.kb-embed-note {
    margin-top: 16px !important;
    text-align: center;
}

@media (max-width: 700px) {
    .kb-embed { height: 72vh; min-height: 440px; }
}

.citation {
    position: relative;
}

.citation h2 {
    margin-bottom: 18px;
}

.copy-button {
    position: absolute;
    top: 28px;
    right: 30px;
    min-width: 126px;
    background: var(--green);
}

.copy-button:hover {
    background: #0b5f59;
}

pre {
    overflow-x: auto;
    padding: 22px;
    border: 1px solid #d9e1ea;
    border-radius: 10px;
    background: #f4f7fb;
    color: #263238;
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', monospace;
    font-size: 0.9rem;
    line-height: 1.5;
}

footer {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 12px;
    margin: 34px 0 4px;
    color: var(--muted);
    font-size: 0.88rem;
}

@media (max-width: 900px) {
    body {
        margin-top: 24px;
        padding: 0 22px;
    }

    h1 {
        font-size: 2.05rem;
    }

    .summary-grid,
    .stage-grid,
    .probe-grid {
        grid-template-columns: 1fr;
    }

    .summary-grid div,
    .stage-grid div {
        min-height: 0;
    }

    .copy-button {
        position: static;
        margin: 0 auto 18px;
    }
}

@media (max-width: 560px) {
    body {
        padding: 0 14px;
    }

    h1 {
        font-size: 1.6rem;
    }

    h2 {
        font-size: 1.45rem;
    }

    .section,
    .figure-wrap {
        padding: 18px;
        border-radius: 12px;
    }

    .media-panel {
        border-radius: 12px;
    }

    .chapters {
        padding: 16px 16px 20px;
    }

    .links {
        gap: 10px;
    }

    .links a {
        flex: 1 1 130px;
    }
}

/* --- Simulation Demos --- */
.figure-wrap video {
    width: 100%;
    border-radius: 12px;
    display: block;
    background: #0b0d11;
}
.demo-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    align-items: start;
}
.demo-grid .figure-wrap {
    margin: 0;
}
.demo-grid .figure-wrap video {
    aspect-ratio: 16 / 9;
}
@media (max-width: 900px) {
    .demo-grid {
        grid-template-columns: 1fr;
    }
}