:root {
  color-scheme: light;
  font-family: Inter, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: #171817;
  background: #f7f8f4;
  font-synthesis: none;
  --ink: #171817;
  --muted: #666b65;
  --line: #d8dbd3;
  --surface: #f7f8f4;
  --paper: #ffffff;
  --lime: #a8f238;
  --lime-dark: #4b740b;
  --blue: #2367e8;
  --coral: #ef6a4b;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; min-width: 320px; background: var(--surface); }
a { color: inherit; text-decoration: none; }
button, a { -webkit-tap-highlight-color: transparent; }
img { max-width: 100%; }

.topbar {
  position: fixed;
  inset: 0 0 auto;
  z-index: 30;
  height: 70px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  padding: 0 42px;
  border-bottom: 1px solid transparent;
  transition: background .2s ease, border-color .2s ease;
}
.topbar.is-scrolled { background: rgba(247, 248, 244, .94); border-color: var(--line); backdrop-filter: blur(16px); }
.brand { display: inline-flex; align-items: center; gap: 11px; width: fit-content; font-size: 18px; font-weight: 760; }
.brand-mark { position: relative; width: 34px; height: 34px; display: grid; place-items: center; border: 2px solid var(--ink); border-radius: 8px; background: var(--ink); }
.brand-mark i { position: absolute; width: 6px; height: 6px; border-radius: 50%; background: var(--lime); }
.brand-mark i:nth-child(1) { transform: translate(-8px, 6px); }
.brand-mark i:nth-child(2) { transform: translate(0, -7px); }
.brand-mark i:nth-child(3) { transform: translate(8px, 6px); }
.brand-mark::before, .brand-mark::after { content: ""; position: absolute; width: 12px; height: 1px; top: 19px; background: var(--lime); }
.brand-mark::before { left: 7px; transform: rotate(-48deg); }
.brand-mark::after { right: 7px; transform: rotate(48deg); }
.topbar nav { display: flex; align-items: center; gap: 30px; font-size: 14px; color: #424642; }
.topbar nav a, .github-link { padding: 8px 0; border-bottom: 1px solid transparent; }
.topbar nav a:hover, .topbar nav a:focus-visible, .github-link:hover, .github-link:focus-visible { border-color: var(--ink); }
.github-link { justify-self: end; font-size: 14px; font-weight: 700; }

.hero {
  position: relative;
  min-height: 760px;
  height: 92vh;
  max-height: 900px;
  display: grid;
  place-items: center;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
  isolation: isolate;
}
.hero-image { position: absolute; inset: 0; z-index: -2; background: url('/assets/opc-studio-home.png') center 42% / cover no-repeat; opacity: .13; filter: saturate(.5) contrast(.9); }
.hero-wash { position: absolute; inset: 0; z-index: -1; background: rgba(247, 248, 244, .82); }
.hero::before, .hero::after { content: ""; position: absolute; pointer-events: none; }
.hero::before { inset: 112px 7% 82px; border: 1px solid rgba(69, 78, 67, .16); }
.hero::after { top: 112px; bottom: 82px; left: 50%; border-left: 1px solid rgba(69, 78, 67, .12); }
.hero-content { position: relative; z-index: 2; width: min(940px, calc(100% - 48px)); text-align: center; padding-top: 52px; }
.status { display: inline-flex; align-items: center; gap: 8px; margin: 0 0 30px; padding: 7px 11px; border: 1px solid #bfc5b9; border-radius: 6px; background: rgba(255,255,255,.66); font-size: 12px; font-weight: 750; }
.status span { width: 8px; height: 8px; border-radius: 50%; background: var(--lime); box-shadow: 0 0 0 3px rgba(168,242,56,.22); }
h1 { margin: 0; font-family: Georgia, "Times New Roman", "Noto Serif SC", serif; font-size: 104px; line-height: .92; font-weight: 700; letter-spacing: 0; }
.hero-tagline { margin: 20px 0 0; font-size: 30px; line-height: 1.2; font-weight: 780; }
.hero-tagline::after { content: ""; display: block; width: 114px; height: 7px; margin: 17px auto 0; background: var(--lime); }
.hero-copy { margin: 26px auto 30px; max-width: 760px; color: #4f544e; font-size: 18px; line-height: 1.75; }
.hero-actions { display: flex; justify-content: center; flex-wrap: wrap; gap: 12px; }
.button { min-height: 52px; display: inline-flex; align-items: center; justify-content: center; gap: 11px; padding: 0 22px; border: 1px solid var(--ink); border-radius: 8px; font-weight: 760; transition: transform .16s ease, box-shadow .16s ease, background .16s ease; }
.button:hover { transform: translateY(-2px); box-shadow: 0 8px 0 rgba(23,24,23,.12); }
.button-primary { background: var(--ink); color: #fff; }
.button-primary:hover { background: #2b2d2a; }
.button-secondary { background: rgba(255,255,255,.72); }
.hero-note { margin: 16px 0 0; color: #757b73; font-size: 12px; }
.hero-next { position: absolute; z-index: 2; bottom: 26px; left: 50%; display: flex; flex-direction: column; align-items: center; gap: 8px; color: #666b65; font-size: 11px; transform: translateX(-50%); }
.hero-next i { width: 1px; height: 22px; background: var(--ink); }

.proof-band { display: grid; grid-template-columns: repeat(4, 1fr); border-bottom: 1px solid var(--line); background: var(--paper); }
.proof-band div { min-height: 112px; display: flex; flex-direction: column; justify-content: center; padding: 24px 30px; border-right: 1px solid var(--line); }
.proof-band div:last-child { border-right: 0; }
.proof-band strong { font-size: 15px; }
.proof-band span { margin-top: 7px; color: var(--muted); font-size: 12px; }

section:not(.hero):not(.proof-band) { padding: 104px max(42px, calc((100vw - 1180px) / 2)); }
.eyebrow { margin: 0 0 14px; color: var(--lime-dark); font: 800 12px ui-monospace, SFMono-Regular, Consolas, monospace; }
h2 { margin: 0; font-size: 54px; line-height: 1.1; font-weight: 760; letter-spacing: 0; }
.section-intro { display: grid; grid-template-columns: 1.25fr .75fr; gap: 70px; align-items: end; }
.section-intro .eyebrow { grid-column: 1 / -1; margin-bottom: -44px; }
.section-intro > p:last-child { margin: 0 0 4px; color: var(--muted); line-height: 1.8; }
.system { background: var(--surface); }
.system-grid { display: grid; grid-template-columns: repeat(3, 1fr); margin-top: 72px; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.system-grid article { min-height: 380px; padding: 28px; border-right: 1px solid var(--line); }
.system-grid article:last-child { border-right: 0; }
.number { color: var(--coral); font: 800 12px ui-monospace, SFMono-Regular, Consolas, monospace; }
.system-grid h3 { margin: 30px 0 12px; font-size: 22px; }
.system-grid p { margin: 0; color: var(--muted); line-height: 1.75; }
.mini-diagram { position: relative; height: 126px; margin-top: 34px; }
.mini-diagram i { position: absolute; display: block; width: 30px; height: 30px; border: 1px solid var(--ink); border-radius: 50%; background: var(--paper); }
.mini-diagram::before, .mini-diagram::after { content: ""; position: absolute; background: var(--ink); }
.org-diagram i:nth-child(1) { left: calc(50% - 15px); top: 0; background: var(--lime); }
.org-diagram i:nth-child(2) { left: 12%; bottom: 0; }
.org-diagram i:nth-child(3) { left: calc(50% - 15px); bottom: 0; }
.org-diagram i:nth-child(4) { right: 12%; bottom: 0; }
.org-diagram::before { top: 30px; left: 50%; width: 1px; height: 50px; }
.org-diagram::after { left: calc(12% + 15px); right: calc(12% + 15px); bottom: 45px; height: 1px; }
.graph-diagram i:nth-child(1) { left: 5%; top: 42px; background: var(--lime); }
.graph-diagram i:nth-child(2) { left: 38%; top: 4px; }
.graph-diagram i:nth-child(3) { right: 8%; top: 30px; }
.graph-diagram i:nth-child(4) { left: 45%; bottom: 0; }
.graph-diagram::before { left: 19%; top: 62px; width: 68%; height: 1px; transform: rotate(-10deg); }
.graph-diagram::after { left: 47%; top: 31px; width: 1px; height: 80px; transform: rotate(-8deg); }
.evidence-diagram i { width: 92%; height: 24px; left: 4%; border-radius: 4px; }
.evidence-diagram i:nth-child(1) { top: 8px; background: var(--lime); }
.evidence-diagram i:nth-child(2) { top: 50px; }
.evidence-diagram i:nth-child(3) { top: 92px; }
.evidence-diagram::before { width: 8px; height: 8px; border-radius: 50%; right: 8%; top: 16px; background: var(--ink); }
.evidence-diagram::after { display: none; }

.product { background: #191b19; color: #fff; }
.product-heading { display: grid; grid-template-columns: 1.25fr .75fr; gap: 70px; align-items: end; }
.product-heading .eyebrow { color: var(--lime); }
.product-heading > p { margin: 0 0 4px; color: #b7bdb5; line-height: 1.8; }
.product-window { margin: 60px 0 0; }
.window-bar { height: 42px; display: flex; align-items: center; gap: 7px; padding: 0 14px; color: #858b84; background: #292c29; border: 1px solid #414541; border-bottom: 0; font-size: 11px; }
.window-bar span { width: 8px; height: 8px; border-radius: 50%; background: #636963; }
.window-bar span:first-child { background: var(--coral); }
.window-bar b { margin-left: 8px; font-weight: 600; }
.product-window img { width: 100%; display: block; border: 1px solid #414541; background: #fff; }
.product-window figcaption { margin-top: 10px; color: #858b84; font-size: 11px; }
.workflow { margin: 44px 0 0; padding: 0; display: grid; grid-template-columns: repeat(5, 1fr); list-style: none; border-top: 1px solid #414541; }
.workflow li { position: relative; padding: 20px 12px 0 0; color: #c8cdc7; font-size: 13px; }
.workflow li::before { content: ""; position: absolute; top: -4px; left: 0; width: 8px; height: 8px; border-radius: 50%; background: var(--lime); }
.workflow span { display: block; margin-bottom: 7px; color: #757b74; font: 700 10px ui-monospace, SFMono-Regular, Consolas, monospace; }

.providers { text-align: center; background: var(--paper); }
.providers h2 { max-width: 820px; margin: 0 auto; }
.provider-row { display: flex; flex-wrap: wrap; justify-content: center; margin: 54px auto 0; max-width: 1080px; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.provider-row span { flex: 1 1 160px; padding: 25px 18px; border-right: 1px solid var(--line); font-size: 14px; font-weight: 760; }
.provider-row span:last-child { border-right: 0; }
.providers-note { margin: 22px 0 0; color: var(--muted); font-size: 13px; }

.release { display: grid; grid-template-columns: 1.1fr .9fr; gap: 100px; background: var(--lime); }
.release-main > p:not(.eyebrow) { max-width: 600px; margin: 24px 0 30px; line-height: 1.75; }
.release .eyebrow { color: #344d0e; }
.release-actions { display: flex; align-items: center; flex-wrap: wrap; gap: 22px; }
.text-link { font-size: 14px; font-weight: 760; border-bottom: 1px solid var(--ink); }
.release-facts { margin: 0; border-top: 1px solid rgba(23,24,23,.35); }
.release-facts div { display: grid; grid-template-columns: 100px 1fr; gap: 18px; padding: 17px 0; border-bottom: 1px solid rgba(23,24,23,.35); }
.release-facts dt { color: #3e521f; font-size: 12px; }
.release-facts dd { margin: 0; font-size: 14px; font-weight: 700; }
.release-facts a { border-bottom: 1px solid var(--ink); }

.boundary { display: grid; grid-template-columns: .8fr 1.2fr; gap: 60px; align-items: start; background: #e8ebe4; }
.boundary h2 { font-size: 36px; }
.boundary p { margin: 0; color: #565c55; line-height: 1.75; }
.boundary a { grid-column: 2; width: fit-content; margin-top: -28px; font-size: 13px; font-weight: 760; border-bottom: 1px solid var(--ink); }

footer { min-height: 160px; padding: 38px 42px; display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; gap: 30px; background: var(--ink); color: #fff; }
.footer-brand .brand-mark { border-color: #fff; background: #fff; }
.footer-brand .brand-mark i, .footer-brand .brand-mark::before, .footer-brand .brand-mark::after { background: var(--ink); }
footer p { color: #9da39c; font-size: 13px; }
footer > div { justify-self: end; display: flex; gap: 20px; color: #c9cdc8; font-size: 12px; }
footer a:hover { color: var(--lime); }
.toast { position: fixed; right: 20px; bottom: 20px; z-index: 40; max-width: calc(100% - 40px); padding: 12px 16px; border: 1px solid #303330; border-radius: 6px; background: var(--ink); color: #fff; font-size: 13px; box-shadow: 0 16px 40px rgba(0,0,0,.2); }

@media (max-width: 900px) {
  .topbar { padding: 0 24px; grid-template-columns: 1fr auto; }
  .topbar nav { display: none; }
  h1 { font-size: 76px; }
  .hero-tagline { font-size: 25px; }
  .proof-band { grid-template-columns: 1fr 1fr; }
  .proof-band div:nth-child(2) { border-right: 0; }
  .proof-band div:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  section:not(.hero):not(.proof-band) { padding: 78px 28px; }
  .section-intro, .product-heading, .release, .boundary { grid-template-columns: 1fr; gap: 28px; }
  .section-intro .eyebrow { grid-column: auto; margin-bottom: -10px; }
  .system-grid { grid-template-columns: 1fr; }
  .system-grid article { min-height: 310px; border-right: 0; border-bottom: 1px solid var(--line); }
  .system-grid article:last-child { border-bottom: 0; }
  .workflow { grid-template-columns: repeat(3, 1fr); row-gap: 25px; }
  .boundary a { grid-column: auto; margin-top: 0; }
  footer { grid-template-columns: 1fr; text-align: center; }
  .footer-brand, footer > div { justify-self: center; }
}

@media (max-width: 600px) {
  .topbar { height: 62px; padding: 0 18px; }
  .brand { font-size: 16px; }
  .brand-mark { width: 30px; height: 30px; }
  .github-link { font-size: 12px; }
  .hero { min-height: 700px; height: 88vh; }
  .hero::before { inset: 92px 18px 70px; }
  .hero::after { display: none; }
  .hero-content { width: calc(100% - 36px); padding-top: 38px; }
  .status { margin-bottom: 24px; }
  h1 { font-size: 52px; }
  .hero-tagline { font-size: 21px; }
  .hero-copy { font-size: 15px; line-height: 1.7; }
  .hero-copy br { display: none; }
  .hero-actions { flex-direction: column; align-items: stretch; padding: 0 8px; }
  .button { width: 100%; }
  .proof-band { grid-template-columns: 1fr; }
  .proof-band div { min-height: 92px; border-right: 0; border-bottom: 1px solid var(--line); }
  .proof-band div:last-child { border-bottom: 0; }
  section:not(.hero):not(.proof-band) { padding: 64px 20px; }
  h2 { font-size: 36px; }
  .system-grid article { padding: 24px 18px; }
  .product-window { margin-top: 38px; }
  .window-bar b { max-width: 190px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
  .workflow { grid-template-columns: 1fr 1fr; }
  .provider-row span { flex-basis: 50%; border-bottom: 1px solid var(--line); }
  .provider-row span:nth-child(even) { border-right: 0; }
  .release-main h2 { font-size: 40px; }
  .release-actions { align-items: flex-start; flex-direction: column; }
  .release-facts div { grid-template-columns: 82px 1fr; }
  .boundary h2 { font-size: 30px; }
  footer { padding: 36px 20px; }
  footer > div { flex-wrap: wrap; justify-content: center; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .topbar, .button { transition: none; }
}