@charset "UTF-8";

:root {
  color-scheme: dark;
  --bg: #141614;
  --surface: #1a1d19;
  --text: #f0f1e9;
  --muted: #a0a59b;
  --faint: #858d7f;
  --line: #343a30;
  --accent: #d1f68a;
  --accent-ink: #172011;
  --drawing: #a3b096;
  --drawing-accent: #cbed99;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --sans: "Segoe UI", -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
}

:root[data-theme="light"] {
  color-scheme: light;
  --bg: #f2f3ec;
  --surface: #e9ede1;
  --text: #22281e;
  --muted: #606a59;
  --faint: #5f6958;
  --line: #cbd2c3;
  --accent: #43602c;
  --accent-ink: #f8fbed;
  --drawing: #66765a;
  --drawing-accent: #48672f;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 100px; }
body { margin: 0; background: var(--bg); color: var(--text); font-family: var(--sans); -webkit-font-smoothing: antialiased; }
button, a { -webkit-tap-highlight-color: transparent; }
button { font: inherit; }
a { color: inherit; text-decoration: none; }
button, a { touch-action: manipulation; }
button { cursor: pointer; }
::selection { background: var(--accent); color: var(--accent-ink); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 5px; }
.container { width: min(1240px, calc(100% - 112px)); margin-inline: auto; }
.icon-library { position: absolute; width: 0; height: 0; overflow: hidden; }
.icon { width: 22px; height: 22px; fill: none; stroke: currentColor; stroke-width: 1.5; stroke-linecap: round; stroke-linejoin: round; flex-shrink: 0; }
.icon.small { width: 15px; height: 15px; }
.solid-icon { fill: currentColor; stroke: none; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }
.skip-link { position: fixed; left: 20px; top: 14px; z-index: 10; padding: 12px 18px; background: var(--accent); color: var(--accent-ink); transform: translateY(-180%); }
.skip-link:focus { transform: translateY(0); }
.site-header { height: 96px; border-bottom: 1px solid var(--line); }
.header-inner { height: 100%; display: flex; align-items: center; gap: 38px; }
.wordmark { font-size: 29px; font-weight: 700; letter-spacing: -1.5px; white-space: nowrap; }
.wordmark span { color: var(--accent); }
.navigation { margin-left: auto; display: flex; align-items: center; gap: 30px; font-size: 13px; }
.navigation a { display: inline-flex; align-items: center; gap: 5px; min-height: 44px; color: var(--muted); transition: color .18s ease; }
.navigation a:hover { color: var(--text); }
.header-controls { display: flex; align-items: center; gap: 22px; }
.language-switch { display: flex; align-items: center; gap: 8px; color: var(--faint); font-size: 12px; white-space: nowrap; }
.language-switch a { padding: 0 2px; color: var(--muted); min-height: 44px; display: inline-flex; align-items: center; }
.language-switch a[aria-current="page"] { color: var(--text); }
.icon-button { display: grid; place-content: center; width: 42px; height: 42px; border: 1px solid var(--line); border-radius: 50%; background: transparent; color: var(--text); transition: border-color .18s ease, background .18s ease; }
.icon-button:hover { border-color: var(--muted); background: var(--surface); }
.theme-toggle .icon { width: 18px; height: 18px; }
.menu-toggle { display: none; }
.hero { padding-top: 78px; display: grid; grid-template-columns: 1.08fr 1fr; column-gap: 26px; }
.eyebrow { display: flex; align-items: center; gap: 10px; margin: 0 0 28px; font-family: var(--mono); font-size: 11px; letter-spacing: 1.5px; color: var(--muted); }
.status-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--accent); }
h1 { font-size: clamp(76px, 7.8vw, 110px); line-height: 1.01; letter-spacing: -.07em; font-weight: 600; margin: 0 0 26px; }
.title-dot { color: var(--accent); }
.hero-subtitle { font-family: var(--mono); font-size: clamp(10px, 1vw, 13px); line-height: 1.9; margin: 0 0 26px; letter-spacing: -.15px; white-space: nowrap; color: var(--text); }
.hero-subtitle span { color: var(--faint); padding-inline: 1px; }
.mobile-break { display: none; }
.hero-description { max-width: 475px; font-size: 14px; line-height: 1.95; color: var(--muted); }
.hero-description p { margin: 0 0 8px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 31px; }
.button { min-height: 48px; padding: 13px 21px; border: 1px solid var(--line); font-size: 13px; font-weight: 500; display: inline-flex; align-items: center; justify-content: center; gap: 20px; border-radius: 3px; transition: transform .18s ease, border-color .18s ease, background .18s ease; }
.button:hover { transform: translateY(-3px); }
.button-primary { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }
.button-secondary { gap: 10px; }
.button-secondary .icon:first-child { width: 17px; height: 17px; }
.button-secondary .icon:last-child { margin-left: 10px; }
.button-secondary:hover { border-color: var(--muted); background: var(--surface); }
.hero-visual { align-self: start; margin-top: 12px; min-width: 0; position: relative; }
.drawing-top, .drawing-bottom { display: flex; align-items: center; justify-content: space-between; color: var(--faint); font-family: var(--mono); font-size: 9px; letter-spacing: .5px; }
.drawing-top { margin-inline: 20px; }
.drawing-cross { font-size: 20px; color: var(--drawing-accent); }
.drawing-bottom { margin: -15px 20px 0; font-size: 8px; }
.mechanism { display: block; width: 100%; color: var(--drawing); }
.construction, .assembly-lines { opacity: .45; }
.surface { fill: var(--bg); }
.mechanism-ring { color: var(--drawing-accent); }
.mechanism-base { opacity: .8; }
.drawing-callouts { opacity: .6; }
.drawing-labels { font-family: var(--mono); font-size: 8px; }
.hero-baseline { grid-column: 1 / -1; border-top: 1px solid var(--line); margin-top: 65px; padding: 22px 0; display: flex; align-items: center; gap: 24px; }
.baseline-note { font-size: 11px; color: var(--muted); }
.discipline-list { display: flex; gap: 35px; margin-left: auto; font-family: var(--mono); font-size: 10px; letter-spacing: .4px; }
.discipline-list b { font-weight: 400; color: var(--faint); margin-right: 9px; }
.scroll-cue { display: grid; place-items: center; height: 36px; width: 36px; margin-left: 10px; border: 1px solid var(--line); border-radius: 50%; color: var(--muted); }
.scroll-cue .icon { width: 15px; height: 15px; }
.section { border-top: 1px solid var(--line); padding-block: 62px 76px; }
.section-label { display: flex; align-items: center; gap: 12px; font-size: 11px; margin-bottom: 40px; }
.section-number { font-family: var(--mono); color: var(--accent); }
.label-english { color: var(--faint); font-family: var(--mono); font-size: 9px; letter-spacing: 1px; margin-left: 5px; }
.about-grid { display: grid; grid-template-columns: 1.08fr 1fr; gap: 70px; }
h2 { font-size: clamp(33px, 3.4vw, 48px); font-weight: 500; line-height: 1.5; letter-spacing: -.045em; margin: 0; }
.muted-heading { color: var(--muted); }
.about-copy { font-size: 14px; line-height: 2; color: var(--muted); padding-top: 2px; }
.about-copy p { margin: 0 0 16px; }
.about-signature { display: flex; align-items: center; gap: 12px; margin-top: 30px; font-family: var(--mono); font-size: 9px; letter-spacing: .5px; color: var(--faint); }
.signature-line { width: 26px; height: 1px; background: var(--accent); }
.section-intro { display: flex; justify-content: space-between; align-items: end; gap: 40px; margin-bottom: 36px; }
.section-intro > p { max-width: 390px; margin: 0 0 9px; color: var(--muted); font-size: 13px; line-height: 1.85; }
.focus-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.focus-card { min-width: 0; padding: 30px 32px 12px; border: 1px solid var(--line); background: var(--surface); display: flex; flex-direction: column; transition: border-color .18s ease; }
.focus-card:hover { border-color: var(--faint); }
.card-masthead { display: flex; justify-content: space-between; align-items: start; gap: 20px; margin-bottom: 24px; }
.card-index { color: var(--accent); font-family: var(--mono); font-size: 10px; letter-spacing: .8px; }
.focus-icon { width: 43px; height: 43px; fill: none; stroke: var(--drawing-accent); stroke-width: 1.25; stroke-linecap: round; stroke-linejoin: round; }
.focus-card h3 { font-size: 23px; font-weight: 500; line-height: 1.45; letter-spacing: -.035em; margin: 0 0 16px; }
.focus-brief { color: var(--muted); font-size: 13px; line-height: 1.85; margin: 0 0 24px; }
.card-caption { color: var(--faint); font-family: var(--mono); font-size: 9px; letter-spacing: .7px; margin: 0 0 12px; }
.topic-tags { display: flex; flex-wrap: wrap; gap: 7px; padding: 0; margin: 0 0 24px; list-style: none; }
.topic-tags li { padding: 5px 8px; border: 1px solid var(--line); border-radius: 2px; font-size: 10px; line-height: 1.6; color: var(--muted); overflow-wrap: anywhere; max-width: 100%; }
details summary { cursor: pointer; display: flex; align-items: center; justify-content: space-between; gap: 16px; list-style: none; min-height: 48px; font-size: 12px; line-height: 1.6; }
details summary::-webkit-details-marker { display: none; }
details summary::marker { content: ""; }
details summary:hover { color: var(--accent); }
.details-plus { width: 14px; height: 14px; position: relative; flex-shrink: 0; }
.details-plus::before, .details-plus::after { content: ""; position: absolute; background: currentColor; }
.details-plus::before { width: 12px; height: 1px; top: 6px; left: 1px; }
.details-plus::after { width: 1px; height: 12px; left: 6px; top: 1px; transition: transform .18s ease; }
details[open] > summary .details-plus::after { transform: rotate(90deg); }
.focus-detail { margin-top: auto; border-top: 1px solid var(--line); }
.focus-detail-body { padding-block: 4px 14px; color: var(--muted); font-size: 13px; line-height: 1.9; }
.focus-detail-body p { margin: 0 0 12px; }
.explorations-list { display: grid; gap: 18px; }
.exploration-card { border: 1px solid var(--line); padding: 34px; display: grid; grid-template-columns: 190px minmax(0, 1fr); gap: 38px; }
.project-identity { min-width: 0; border-right: 1px solid var(--line); padding-right: 24px; }
.project-diagram { display: block; width: 100%; margin-block: 26px 16px; fill: none; stroke: var(--drawing-accent); stroke-width: 1.3; stroke-linecap: round; stroke-linejoin: round; }
.diagram-frame { stroke: var(--line); }
.project-category { color: var(--faint); font-family: var(--mono); font-size: 8px; line-height: 1.8; letter-spacing: .4px; display: block; }
.project-content { min-width: 0; }
.project-title-row { display: flex; align-items: start; flex-wrap: wrap; justify-content: space-between; gap: 14px 20px; margin-bottom: 22px; }
.project-title-row h3 { margin: 0; font-size: 26px; line-height: 1.5; font-weight: 500; letter-spacing: -.035em; }
.project-status { display: inline-flex; align-items: center; gap: 7px; padding: 5px 8px; margin-top: 5px; border: 1px solid var(--line); font-size: 10px; line-height: 1.6; color: var(--muted); }
.project-status > span:first-child { width: 4px; height: 4px; border-radius: 50%; background: var(--accent); flex-shrink: 0; }
.project-description { font-size: 13px; line-height: 1.9; color: var(--muted); }
.project-description p { margin: 0 0 10px; }
.project-stack { margin-block: 22px 20px; }
.project-stack .card-caption { display: block; }
.project-stack .topic-tags { margin-bottom: 0; }
.project-stack .topic-tags li { font-family: var(--mono); font-size: 9px; }
.project-details { border-top: 1px solid var(--line); }
.project-detail-grid { display: grid; grid-template-columns: 1.15fr 1fr; gap: 30px; padding-block: 20px 5px; }
.project-detail-grid h4 { margin: 0 0 14px; font-size: 10px; font-weight: 500; letter-spacing: .5px; color: var(--accent); }
.challenge-list { padding: 0; margin: 0; list-style: none; display: grid; gap: 10px; }
.challenge-list li { position: relative; padding-left: 14px; color: var(--muted); font-size: 12px; line-height: 1.85; }
.challenge-list li::before { content: ""; position: absolute; left: 0; top: .85em; width: 4px; height: 4px; border: 1px solid var(--faint); }
.current-stage { border-left: 1px solid var(--line); padding-left: 26px; }
.current-stage p { color: var(--muted); font-size: 12px; line-height: 1.95; margin: 0; }
.github-section { margin-block: 30px 78px; border: 1px solid var(--line); background: var(--surface); padding: 44px; display: flex; gap: 30px; align-items: center; justify-content: space-between; }
.github-section .eyebrow { font-size: 9px; margin-bottom: 17px; color: var(--accent); }
.github-section h2 { font-size: 34px; line-height: 1.35; }
.github-section p:not(.eyebrow) { color: var(--muted); font-size: 12px; margin-bottom: 0; line-height: 1.8; }
.github-link { display: flex; align-items: center; gap: 40px; border-bottom: 1px solid var(--muted); padding-block: 18px; transition: color .18s ease; }
.github-link:hover { color: var(--accent); }
.github-link-text { display: flex; align-items: center; gap: 13px; font-family: var(--mono); font-size: 12px; }
.github-arrow { width: 27px; height: 27px; transition: transform .18s ease; }
.github-link:hover .github-arrow { transform: translate(3px, -3px); }
.site-footer { border-top: 1px solid var(--line); padding-block: 29px; display: flex; align-items: center; gap: 30px; }
.site-footer .wordmark { font-size: 24px; }
.site-footer p { font-family: var(--mono); font-size: 10px; color: var(--muted); }
.footer-note { color: var(--faint); font-family: var(--mono); font-size: 8px; letter-spacing: .3px; margin-left: auto; }
.back-top { display: inline-flex; align-items: center; gap: 10px; color: var(--muted); font-size: 10px; min-height: 44px; margin-left: auto; }
html[lang="en"] .about-grid h2 { font-size: clamp(30px, 3.2vw, 44px); }

@media (min-width: 1600px) {
  .hero { padding-top: 100px; }
}

@media (max-width: 1080px) {
  .container { width: calc(100% - 72px); }
  .header-inner { gap: 25px; }
  .navigation { gap: 19px; font-size: 12px; }
  .header-controls { gap: 12px; }
  .hero { column-gap: 15px; padding-top: 65px; }
  .hero-subtitle { white-space: normal; }
  .hero-description { font-size: 13px; }
  .hero-baseline { margin-top: 50px; }
  .about-grid { gap: 40px; }
  .drawing-labels { font-size: 8px; }
  .github-section { padding: 32px; }
  .github-link { gap: 20px; }
  .footer-note { display: none; }
}

@media (max-width: 800px) {
  .container { width: calc(100% - 48px); }
  .site-header { height: 80px; }
  .header-inner { gap: 16px; }
  .header-controls { margin-left: auto; gap: 14px; }
  .wordmark { font-size: 27px; }
  .menu-toggle { display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 5px; border-radius: 3px; }
  .menu-toggle span { height: 1px; width: 16px; background: currentColor; transition: transform .18s ease; }
  .menu-toggle[aria-expanded="true"] span:first-child { transform: translateY(3px) rotate(45deg); }
  .menu-toggle[aria-expanded="true"] span:last-child { transform: translateY(-3px) rotate(-45deg); }
  .navigation { display: none; position: absolute; z-index: 5; left: 0; right: 0; top: 79px; margin: 0; padding: 18px 24px 22px; background: var(--bg); border-bottom: 1px solid var(--line); }
  .navigation.is-open { display: grid; grid-template-columns: 1fr 1fr; gap: 5px 20px; }
  .navigation a { padding: 7px 0; color: var(--text); font-size: 14px; }
  .hero { padding-top: 56px; column-gap: 12px; grid-template-columns: 1.15fr 1fr; }
  h1 { font-size: clamp(68px, 10vw, 82px); }
  .eyebrow { font-size: 9px; letter-spacing: 1px; }
  .hero-visual { margin-top: 60px; }
  .drawing-top { font-size: 7px; margin-inline: 8px; }
  .drawing-bottom { font-size: 6px; margin-inline: 8px; }
  .hero-subtitle { font-size: 10px; }
  .hero-actions { gap: 9px; }
  .button { padding-inline: 15px; font-size: 12px; gap: 14px; }
  .discipline-list { gap: 20px; font-size: 9px; }
  .discipline-list b { margin-right: 5px; }
  .baseline-note { font-size: 10px; }
  .hero-baseline { gap: 10px; }
  .section { padding-block: 45px 55px; }
  .section-label { margin-bottom: 30px; }
  .about-grid { gap: 30px; }
  h2 { font-size: 32px; }
  .about-copy { font-size: 13px; }
  .section-intro { align-items: start; gap: 24px; }
  .section-intro > p { max-width: 300px; font-size: 12px; }
  .focus-card { padding: 24px 22px 10px; }
  .focus-card h3 { font-size: 20px; }
  .exploration-card { grid-template-columns: 1fr; gap: 24px; padding: 26px; }
  .project-identity { display: flex; align-items: center; gap: 24px; padding: 0 0 12px; border-right: 0; border-bottom: 1px solid var(--line); }
  .project-diagram { width: 85px; margin: 0 0 0 auto; order: 3; }
  .project-category { max-width: 160px; font-size: 8px; }
  .project-title-row h3 { font-size: 24px; }
  .project-detail-grid { gap: 24px; }
  .github-section { margin-block: 20px 55px; padding: 30px; flex-direction: column; align-items: stretch; gap: 20px; }
  .github-link { justify-content: space-between; }
}

@media (max-width: 580px) {
  .container { width: calc(100% - 40px); }
  .site-header { height: 74px; }
  .navigation { top: 73px; padding-inline: 20px; }
  .header-controls { gap: 9px; }
  .language-switch { gap: 5px; font-size: 11px; }
  .icon-button { width: 40px; height: 40px; }
  .hero { display: flex; flex-direction: column; padding-top: 45px; }
  .hero-copy { position: relative; z-index: 1; }
  h1 { font-size: clamp(70px, 17.5vw, 96px); margin-bottom: 24px; }
  .eyebrow { margin-bottom: 23px; }
  .hero-subtitle { font-size: 11px; margin-bottom: 22px; line-height: 1.85; }
  .mobile-break { display: block; }
  .mobile-break + span { display: none; }
  .hero-description { font-size: 13px; line-height: 1.9; }
  .hero-actions { margin-top: 26px; gap: 12px; }
  .button { padding-inline: 19px; min-height: 48px; gap: 19px; }
  .hero-visual { margin: 35px auto 0; width: min(100%, 380px); }
  .drawing-top { font-size: 8px; }
  .drawing-bottom { font-size: 7px; margin-top: -12px; }
  .hero-baseline { display: grid; grid-template-columns: 1fr auto; width: 100%; margin-top: 35px; padding-block: 18px; row-gap: 13px; }
  .baseline-note { font-size: 10px; }
  .discipline-list { grid-column: 1 / -1; grid-row: 2; justify-content: space-between; gap: 8px; margin-left: 0; font-size: 9px; }
  .scroll-cue { grid-column: 2; grid-row: 1; width: 29px; height: 29px; }
  .section { padding-block: 38px 44px; }
  .section-label { font-size: 10px; margin-bottom: 26px; }
  .about-grid { grid-template-columns: 1fr; gap: 25px; }
  h2 { font-size: 37px; }
  .about-copy { font-size: 13px; line-height: 1.95; }
  .about-signature { margin-top: 25px; font-size: 8px; }
  .section-intro { display: block; margin-bottom: 26px; }
  .section-intro > p { margin-top: 14px; max-width: none; }
  .exploration-card { padding: 22px; gap: 24px; }
  .project-identity { gap: 12px; }
  .project-identity .card-index { font-size: 9px; }
  .project-category { max-width: 120px; font-size: 7px; }
  .project-diagram { width: 60px; flex-shrink: 0; }
  .project-title-row { gap: 10px; margin-bottom: 18px; }
  .project-title-row h3 { font-size: 23px; }
  .project-detail-grid { grid-template-columns: 1fr; gap: 26px; padding-block: 16px 6px; }
  .current-stage { padding: 20px 0 0; border-left: 0; border-top: 1px solid var(--line); }
  .github-section { padding: 25px; margin-block: 14px 45px; }
  .github-section h2 { font-size: 28px; }
  .github-link-text { font-size: 11px; gap: 10px; }
  .github-link { gap: 10px; }
  .github-link-text .icon { width: 19px; height: 19px; }
  .site-footer { padding-block: 20px; gap: 15px; flex-wrap: wrap; }
  .site-footer .wordmark { font-size: 23px; }
  .site-footer p { font-size: 9px; }
  .back-top { font-size: 9px; }
  html[lang="en"] .about-grid h2 { font-size: 34px; }
}

@media (max-width: 640px) {
  .focus-grid { grid-template-columns: 1fr; }
  .focus-card { padding: 24px 20px 10px; }
  .focus-card h3 { font-size: 22px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
  .button:hover, .github-link:hover .github-arrow { transform: none; }
}