:root {
  --bg: oklch(1 0 0);
  --surface: oklch(.975 .008 330);
  --surface-strong: oklch(.94 .018 330);
  --ink: oklch(.22 .025 330);
  --muted: oklch(.5 .026 330);
  --line: oklch(.89 .018 330);
  --primary: oklch(.48 .18 332);
  --primary-dark: oklch(.35 .145 332);
  --accent: oklch(.86 .17 80);
  --dark: oklch(.16 .03 330);
  --dark-muted: oklch(.76 .035 330);
  --display: "Arial Rounded MT Bold", "Avenir Next", "PingFang SC", sans-serif;
  --body: "Avenir Next", "PingFang SC", "Microsoft YaHei", sans-serif;
  --radius: 14px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--bg); font-family: var(--body); line-height: 1.65; -webkit-font-smoothing: antialiased; }
a { color: inherit; }
button { font: inherit; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }
.container { width: min(1120px, calc(100% - 40px)); margin: 0 auto; }
.skip-link { position: fixed; z-index: 10; top: 10px; left: 12px; transform: translateY(-160%); padding: 8px 12px; border-radius: 8px; color: var(--dark); background: var(--accent); }
.skip-link:focus { transform: translateY(0); }
.site-header { position: sticky; top: 0; z-index: 5; border-bottom: 1px solid oklch(.22 .025 330 / .1); background: oklch(1 0 0 / .9); backdrop-filter: blur(14px); }
.header-inner { min-height: 70px; display: flex; align-items: center; justify-content: space-between; gap: 20px; }
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; font-weight: 800; letter-spacing: -.025em; }
.brand-mark { width: 30px; height: 30px; display: grid; place-items: center; border-radius: 9px; color: white; background: var(--primary); }
.brand-mark svg { width: 18px; height: 18px; }
.header-nav { display: flex; align-items: center; gap: 22px; color: var(--muted); font-size: .88rem; }
.header-nav a { text-decoration: none; }
.header-nav a:hover { color: var(--primary); }

.hero { overflow: hidden; color: white; background: var(--dark); }
.hero-inner { position: relative; display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(300px, .9fr); gap: clamp(34px, 7vw, 96px); align-items: center; padding: clamp(64px, 9vw, 116px) 0 clamp(68px, 8vw, 108px); }
.hero-copy { max-width: 690px; }
.eyebrow { margin: 0 0 18px; color: var(--accent); font-size: .76rem; font-weight: 900; letter-spacing: .12em; }
h1, h2, h3 { font-family: var(--display); text-wrap: balance; line-height: 1.12; letter-spacing: -.045em; }
h1 { margin: 0; font-size: clamp(2.8rem, 6.2vw, 5.6rem); }
.hero-copy > p:not(.eyebrow) { max-width: 570px; margin: 24px 0 0; color: var(--dark-muted); font-size: clamp(1rem, 1.6vw, 1.2rem); }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 34px; }
.button { display: inline-flex; justify-content: center; align-items: center; min-height: 46px; padding: 10px 17px; border: 1px solid transparent; border-radius: 999px; font-weight: 800; text-decoration: none; cursor: pointer; transition: transform .18s ease, background-color .18s ease, border-color .18s ease; }
.button:hover { transform: translateY(-2px); }
.button-primary { color: white; background: var(--primary); }
.button-primary:hover { background: var(--primary-dark); }
.button-quiet { color: white; border-color: oklch(1 0 0 / .3); }
.button-quiet:hover { border-color: white; background: oklch(1 0 0 / .08); }
.hero-note { display: flex; gap: 9px; align-items: flex-start; margin-top: 30px; color: var(--dark-muted); font-size: .83rem; }
.hero-note svg { flex: 0 0 auto; margin-top: 4px; color: var(--accent); }
.hero-panel { position: relative; padding: 25px; border: 1px solid oklch(1 0 0 / .18); border-radius: var(--radius); background: oklch(.22 .034 330 / .9); transform: rotate(3deg); }
.hero-panel::after { content: ""; position: absolute; inset: 18px -18px -18px 18px; z-index: -1; border: 1px solid oklch(1 0 0 / .15); border-radius: var(--radius); transform: rotate(-7deg); }
.panel-top { display: flex; justify-content: space-between; padding-bottom: 18px; border-bottom: 1px solid oklch(1 0 0 / .13); color: var(--dark-muted); font-size: .74rem; }
.status-dot { width: 9px; height: 9px; display: inline-block; border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 5px oklch(.86 .17 80 / .15); }
.hero-panel h2 { margin: 24px 0 10px; font-size: 2.05rem; }
.hero-panel p { margin: 0; color: var(--dark-muted); font-size: .9rem; }
.panel-list { display: grid; gap: 11px; margin: 23px 0 0; padding: 0; list-style: none; }
.panel-list li { display: flex; gap: 10px; align-items: center; color: white; font-size: .86rem; }
.panel-list li::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: var(--accent); }

.section { padding: clamp(58px, 8vw, 104px) 0; }
.section-heading { display: flex; justify-content: space-between; align-items: end; gap: 30px; margin-bottom: 28px; }
.section-heading h2 { margin: 0; font-size: clamp(2rem, 4vw, 3.5rem); }
.section-heading p { max-width: 470px; margin: 0; color: var(--muted); }
.notice { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-bottom: 62px; }
.notice-item { padding: 18px 20px; border: 1px solid var(--line); border-radius: 10px; background: var(--surface); }
.notice-item strong { display: block; margin-bottom: 5px; color: var(--primary-dark); font-size: .8rem; }
.notice-item p { margin: 0; color: var(--muted); font-size: .88rem; }
.group { margin-top: 62px; }
.group:first-of-type { margin-top: 0; }
.group-title { display: flex; align-items: baseline; gap: 12px; margin: 0 0 18px; font-size: 1.45rem; }
.group-title span { color: var(--muted); font-family: var(--body); font-size: .78rem; font-weight: 600; letter-spacing: .02em; }
.project-list { display: grid; gap: 10px; }
.project-card { display: grid; grid-template-columns: minmax(175px, .45fr) minmax(0, 1fr) 28px; gap: 20px; align-items: start; padding: 19px 20px; border: 1px solid var(--line); border-radius: 10px; background: var(--bg); text-decoration: none; transition: border-color .18s ease, background-color .18s ease, transform .18s ease; }
.project-card:hover { border-color: var(--primary); background: var(--surface); transform: translateX(3px); }
.project-card-title { font-size: 1.02rem; font-weight: 800; }
.project-card-meta { margin-top: 4px; color: var(--primary-dark); font-size: .73rem; font-weight: 900; }
.project-card-copy { color: var(--muted); font-size: .86rem; }
.project-card-copy strong { margin-right: 6px; color: var(--ink); font-size: .72rem; letter-spacing: .04em; }
.project-arrow { color: var(--primary); font-size: 1.35rem; line-height: 1; text-align: right; }
.team-section { margin-top: 76px; padding-top: 52px; border-top: 1px solid var(--line); }
.team-section h2 { margin: 0 0 24px; font-size: 2rem; }
.team-members { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.team-member { display: flex; align-items: center; gap: 14px; padding: 17px; border: 1px solid var(--line); border-radius: 10px; text-decoration: none; transition: border-color .18s ease, background-color .18s ease; }
.team-member:hover { border-color: var(--primary); background: var(--surface); }
.team-member img { width: 52px; height: 52px; border-radius: 50%; object-fit: cover; flex-shrink: 0; }
.team-member .name { display: block; font-weight: 800; }
.team-member .role { display: block; margin-top: 2px; color: var(--muted); font-size: .78rem; }
.join-us { display: grid; grid-template-columns: 1fr auto; gap: 40px; align-items: center; margin-top: 34px; padding: 30px; border-radius: var(--radius); color: white; background: var(--primary); }
.join-us-tag { display: inline-block; margin-bottom: 12px; color: var(--accent); font-size: .72rem; font-weight: 900; letter-spacing: .12em; }
.join-us-title { margin: 0 0 12px; font-size: 2rem; }
.join-us-desc, .join-us-list { max-width: 640px; color: oklch(1 0 0 / .8); font-size: .88rem; }
.join-us-desc { margin: 0 0 15px; }
.join-us-list { display: grid; grid-template-columns: 1fr 1fr; gap: 6px 20px; margin: 0; padding-left: 18px; }
.join-us-qr { text-align: center; }
.join-us-qr img { width: 148px; height: 148px; display: block; border-radius: 10px; background: white; object-fit: cover; }
.join-us-qr span { display: block; margin-top: 8px; color: oklch(1 0 0 / .78); font-size: .72rem; }
.footer { padding: 38px 0 50px; border-top: 1px solid var(--line); color: var(--muted); font-size: .8rem; }
.footer-inner { display: flex; justify-content: space-between; gap: 20px; }
.footer a { color: var(--primary-dark); font-weight: 800; text-decoration: none; }

.library-hero .hero-copy > p:not(.eyebrow) { max-width: 620px; }
.hero-accent { color: var(--accent); }
.library-stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; margin-top: 26px; }
.library-stat { padding: 13px; border: 1px solid oklch(1 0 0 / .16); border-radius: 9px; }
.library-stat strong { display: block; color: white; font-size: 1.35rem; }
.library-stat span { color: var(--dark-muted); font-size: .68rem; }
.filter-bar { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 34px; }
.filter-btn { padding: 8px 14px; border: 1px solid var(--line); border-radius: 999px; color: var(--muted); background: var(--bg); font-size: .8rem; font-weight: 800; cursor: pointer; }
.filter-btn:hover, .filter-btn.active { border-color: var(--primary); color: white; background: var(--primary); }
.case-group.is-hidden { display: none; }
.case-card.is-hidden { display: none; }
.case-summary { margin: 0 0 38px; color: var(--muted); }
.case-summary strong { color: var(--ink); }
.tool-download-section { display: flex; justify-content: space-between; align-items: center; gap: 28px; margin-top: 30px; padding: 24px 30px; border: 1px solid oklch(.78 .1 145); border-radius: var(--radius); background: oklch(.95 .035 145); }
.tool-download-copy { max-width: 650px; }
.tool-download-copy .eyebrow { margin-bottom: 10px; color: var(--primary-dark); }
.tool-download-copy h2 { margin: 0; font-size: clamp(1.55rem, 3vw, 2.25rem); }
.tool-download-copy p:not(.eyebrow) { margin: 8px 0 0; color: var(--muted); font-size: .88rem; }
.contribution-section { display: flex; justify-content: space-between; align-items: center; gap: 28px; margin-top: 64px; padding: 28px 30px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
.contribution-copy { max-width: 650px; }
.contribution-copy .eyebrow { margin-bottom: 10px; color: var(--primary); }
.contribution-copy h2 { margin: 0; font-size: clamp(1.8rem, 3.2vw, 2.7rem); }
.contribution-copy p:not(.eyebrow) { margin: 10px 0 0; color: var(--muted); font-size: .9rem; }

/* Techs 2025 uses a forest-green / lime palette; other pages keep the shared theme. */
.techs-theme {
  --surface: oklch(.975 .012 145);
  --surface-strong: oklch(.94 .028 145);
  --ink: oklch(.22 .035 150);
  --muted: oklch(.48 .04 150);
  --line: oklch(.88 .028 145);
  --primary: oklch(.45 .15 150);
  --primary-dark: oklch(.34 .115 150);
  --accent: oklch(.84 .17 105);
  --dark: oklch(.16 .04 150);
  --dark-muted: oklch(.76 .05 150);
}
.techs-theme .site-header { border-bottom-color: oklch(.22 .04 150 / .12); }
.techs-theme .hero-panel { background: oklch(.22 .045 150 / .9); }
.techs-theme .hero-panel::after { border-color: oklch(1 0 0 / .15); }
.techs-theme .panel-top { border-bottom-color: oklch(1 0 0 / .13); }
.techs-theme .status-dot { box-shadow: 0 0 0 5px oklch(.84 .17 105 / .15); }

@media (max-width: 800px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero-panel { width: min(430px, 100%); margin: 10px auto 0; }
  .notice { grid-template-columns: 1fr; }
  .section-heading { display: block; }
  .section-heading p { margin-top: 13px; }
  .tool-download-section { align-items: flex-start; flex-direction: column; }
  .contribution-section { align-items: flex-start; flex-direction: column; }
  .project-card { grid-template-columns: minmax(130px, .4fr) minmax(0, 1fr) 20px; gap: 14px; }
}
@media (max-width: 560px) {
  .container { width: min(100% - 28px, 1120px); }
  .header-inner { min-height: 62px; }
  .header-nav a:not(:last-child) { display: none; }
  h1 { font-size: clamp(2.5rem, 13vw, 4rem); }
  .hero-actions, .hero-actions .button { width: 100%; }
  .project-card { grid-template-columns: 1fr 24px; gap: 8px; }
  .project-card-copy { grid-column: 1 / -1; padding-top: 3px; }
  .project-arrow { grid-column: 2; grid-row: 1; }
  .team-members { grid-template-columns: 1fr; }
  .join-us { grid-template-columns: 1fr; gap: 24px; padding: 23px 20px; }
  .join-us-list { grid-template-columns: 1fr; }
  .join-us-qr { text-align: left; }
  .footer-inner { display: block; }
  .footer-inner p { margin-top: 12px; }
  .library-stats { grid-template-columns: 1fr; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; animation-duration: .01ms !important; }
}