:root {
  --ink: #10131a;
  --ink-soft: #4a5265;
  --ink-faint: #6f7787;
  --bg: #ffffff;
  --bg-alt: #f6f7f9;
  --bg-dark: #10131a;
  --line: #e3e6ea;
  --accent: #2b5bd7;
  --accent-soft: #eaf0fe;
  --accent-ink: #1e46ab;
  --ok: #0f8a5f;
  --warn: #b06d00;
  --radius: 10px;
  --wrap: 1120px;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 80px; }

body {
  margin: 0;
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.65;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 { line-height: 1.2; letter-spacing: -0.02em; margin: 0 0 .5em; }
h1 { font-size: clamp(2rem, 4.4vw, 3.1rem); }
h2 { font-size: clamp(1.6rem, 3vw, 2.15rem); }
h3 { font-size: 1.12rem; letter-spacing: -0.01em; }
p { margin: 0 0 1em; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 24px; }
.wrap-narrow { max-width: 780px; }

.skip {
  position: absolute; left: -9999px;
  background: var(--ink); color: #fff; padding: 10px 16px; z-index: 100;
}
.skip:focus { left: 12px; top: 12px; }

/* ---------- draft notice ---------- */
.draft-bar {
  background: #1b2030; color: #b6bfd0;
  font-size: .86rem; padding: 9px 0;
}
.draft-bar .wrap { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.draft-bar a { color: #7fb3ff; font-weight: 600; white-space: nowrap; }
.draft-pill {
  flex: none; font: 700 .68rem/1 var(--mono); letter-spacing: .06em; text-transform: uppercase;
  background: var(--warn); color: #fff; padding: 4px 8px; border-radius: 999px;
}

.caveat {
  margin: 20px 0 0; padding: 14px 16px;
  border-left: 3px solid var(--warn); border-radius: 0 8px 8px 0;
  background: #fdf0dc; color: #7a4b00; font-size: .9rem;
}
.caveat strong { color: #5e3a00; }

/* ---------- header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,.88);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.header-inner { display: flex; align-items: center; gap: 24px; height: 64px; }
.brand { display: flex; align-items: center; gap: 9px; color: var(--ink); font-weight: 650; }
.brand:hover { text-decoration: none; }
.brand-mark {
  font-family: var(--mono); font-size: .78rem; font-weight: 700; letter-spacing: .06em;
  background: var(--ink); color: #fff; padding: 4px 7px; border-radius: 6px;
}
.brand-name { font-size: .98rem; }

.nav { display: flex; gap: 20px; margin-left: auto; font-size: .92rem; }
.nav a { color: var(--ink-soft); font-weight: 500; }
.nav a:hover { color: var(--ink); text-decoration: none; }
.nav-repo { color: var(--ink) !important; font-weight: 600 !important; }

.lang { display: flex; border: 1px solid var(--line); border-radius: 7px; overflow: hidden; }
.lang button {
  border: 0; background: #fff; color: var(--ink-faint);
  font: 600 .74rem/1 var(--sans); letter-spacing: .04em;
  padding: 7px 9px; cursor: pointer;
}
.lang button + button { border-left: 1px solid var(--line); }
.lang button[aria-pressed="true"] { background: var(--ink); color: #fff; }

/* ---------- hero ---------- */
.hero {
  padding: 76px 0 84px;
  background:
    radial-gradient(900px 420px at 15% -10%, var(--accent-soft), transparent 70%),
    linear-gradient(180deg, #fff, var(--bg-alt));
  border-bottom: 1px solid var(--line);
}
.hero-grid { display: grid; grid-template-columns: 1.05fr 1fr; gap: 56px; align-items: center; }
.eyebrow {
  font: 600 .78rem/1 var(--mono); letter-spacing: .08em; text-transform: uppercase;
  color: var(--accent-ink); margin-bottom: 18px;
}
.lead { font-size: 1.13rem; color: var(--ink-soft); max-width: 34em; }
.hero-note { font-size: .92rem; color: var(--ink-faint); margin-top: 18px; }

.cta-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 26px; }
.cta-center { justify-content: center; }
.btn {
  display: inline-block; padding: 12px 22px; border-radius: 8px;
  font-weight: 600; font-size: .96rem; border: 1px solid transparent; cursor: pointer;
  transition: transform .12s ease, box-shadow .12s ease;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary { background: var(--accent); color: #fff; box-shadow: 0 2px 12px rgba(43,91,215,.28); }
.btn-primary:hover { background: var(--accent-ink); }
.btn-ghost { border-color: var(--line); background: #fff; color: var(--ink); }
.btn-ghost:hover { border-color: var(--ink-faint); }
.section-dark .btn-ghost { background: transparent; border-color: #3a4152; color: #fff; }
.section-dark .btn-ghost:hover { border-color: #6f7787; }

/* ---------- code ---------- */
/* min-width:0 keeps the pre-formatted code from stretching its grid/flex column. */
.hero-grid > *, .spec-detail > *, .steps > li, .flow-step, .card, .tool, .entry { min-width: 0; }

.hero-code, .code-block {
  margin: 0; border-radius: 12px; overflow: hidden;
  background: var(--bg-dark); border: 1px solid #262c3a;
  box-shadow: 0 18px 44px -22px rgba(16,19,26,.55);
}
.hero-code figcaption, .code-block figcaption {
  display: flex; align-items: center; gap: 6px;
  padding: 10px 14px; background: #171b25; border-bottom: 1px solid #262c3a;
  font: 500 .76rem/1 var(--mono); color: #8892a6;
}
.hero-code figcaption code, .code-block figcaption code { color: #b6bfd0; font-size: .76rem; }
.dot { width: 9px; height: 9px; border-radius: 50%; background: #3a4152; display: inline-block; }
.hero-code pre, .code-block pre { margin: 0; padding: 18px 16px; overflow-x: auto; }
.hero-code code, .code-block code {
  font-family: var(--mono); font-size: .8rem; line-height: 1.75; color: #d5dae4;
  white-space: pre; display: block;
}
.code-block-sm code { font-size: .76rem; }
k { color: #7fb3ff; }
s { color: #8ee0a8; text-decoration: none; }
c { color: #6f7787; font-style: italic; }
t { color: #e08a6b; }

/* ---------- sections ---------- */
.section { padding: 84px 0; }
.section-alt { background: var(--bg-alt); border-block: 1px solid var(--line); }
.section-dark { background: var(--bg-dark); color: #d5dae4; }
.section-dark h2, .section-dark h3, .section-dark strong { color: #fff; }
.section-dark .section-lead { color: #9aa3b4; }
.section-dark code { color: #7fb3ff; }
.section-lead { font-size: 1.08rem; color: var(--ink-soft); max-width: 44em; margin-bottom: 44px; }

p code, li code {
  font-family: var(--mono); font-size: .84em;
  background: var(--accent-soft); color: var(--accent-ink);
  padding: 2px 6px; border-radius: 5px;
}
.section-dark p code { background: #1b2030; }

/* ---------- cards ---------- */
.cards { display: grid; gap: 20px; }
.cards-3 { grid-template-columns: repeat(3, 1fr); }
.cards-2 { grid-template-columns: repeat(3, 1fr); }
.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 24px 22px;
}
.card-icon { font-size: 1.5rem; margin-bottom: 12px; }
.card p { color: var(--ink-soft); font-size: .95rem; margin: 0; }
.card h3 { margin-bottom: .45em; }

.pull {
  margin-top: 44px; padding: 22px 26px; border-left: 3px solid var(--accent);
  background: var(--accent-soft); border-radius: 0 var(--radius) var(--radius) 0;
  font-size: 1.08rem; color: var(--accent-ink);
}
.pull strong { font-weight: 700; }

/* ---------- flow ---------- */
.flow {
  display: grid; grid-template-columns: 1fr auto 1fr auto 1fr;
  align-items: start; gap: 18px; margin-bottom: 64px;
}
.flow-step { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; }
.flow-num {
  display: inline-grid; place-items: center; width: 26px; height: 26px; margin-bottom: 12px;
  border-radius: 50%; background: var(--ink); color: #fff;
  font: 700 .8rem/1 var(--mono);
}
.flow-step p { margin: 0; color: var(--ink-soft); font-size: .93rem; }
.flow-arrow { align-self: center; color: var(--ink-faint); font-size: 1.3rem; }

.spec-detail { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.ticks { list-style: none; padding: 0; margin: 22px 0; }
.ticks li {
  position: relative; padding-left: 28px; margin-bottom: 11px;
  color: var(--ink-soft); font-size: .95rem;
}
.ticks li::before {
  content: "✓"; position: absolute; left: 0; top: -1px;
  color: var(--ok); font-weight: 700;
}
.link-arrow { font-weight: 600; font-size: .95rem; }
.link-arrow::after { content: " →"; }

/* ---------- full spec + contribute ---------- */
.docs-block { margin-top: 72px; padding-top: 56px; border-top: 1px solid var(--line); }
.docs-block > p { color: var(--ink-soft); max-width: 44em; margin-bottom: 28px; }

.docs-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 16px; }
.doc-card {
  display: flex; flex-direction: column; gap: 6px; min-width: 0;
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 20px; color: inherit;
}
.doc-card:hover { text-decoration: none; border-color: var(--accent); box-shadow: 0 8px 24px -18px rgba(16,19,26,.5); }
.doc-icon { font-size: 1.4rem; }
.doc-name { font-weight: 650; font-size: 1rem; color: var(--accent); }
.doc-card:hover .doc-name { color: var(--accent-ink); }
.doc-desc { font-size: .88rem; color: var(--ink-soft); }

.contribute {
  display: flex; align-items: center; justify-content: space-between; gap: 32px; flex-wrap: wrap;
  margin-top: 32px; padding: 26px 28px;
  background: #fff; border: 1px solid var(--line); border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius) var(--radius) 0;
}
.contribute h3 { margin-bottom: .35em; }
.contribute p { margin: 0; color: var(--ink-soft); font-size: .95rem; max-width: 46em; }
.contribute .cta-row { margin-top: 0; flex: none; }

/* ---------- .ics shortcut ---------- */
.shortcut {
  margin-top: 40px; padding: 30px 32px; border-radius: var(--radius);
  background: linear-gradient(180deg, #1b2030, #171b25);
  border: 1px solid var(--accent-ink);
}
.shortcut-tag {
  font: 600 .78rem/1 var(--mono); letter-spacing: .04em; text-transform: uppercase;
  color: #7fb3ff; margin-bottom: 12px;
}
.shortcut h3 { margin-bottom: .5em; }
.shortcut p { color: #9aa3b4; font-size: .96rem; max-width: 62em; }
.shortcut-caveat {
  margin: 18px 0 0; padding: 14px 16px; border-radius: 8px;
  background: #10131a; border: 1px dashed #3a4152; font-size: .9rem !important;
}

/* ---------- steps ---------- */
.steps { list-style: none; counter-reset: s; padding: 0; margin: 0; display: grid; gap: 34px; }
.steps > li {
  border: 1px solid #262c3a; background: #171b25;
  border-radius: var(--radius); padding: 26px 28px;
}
.steps h3 { display: flex; align-items: center; gap: 12px; margin-bottom: .6em; }
.step-num {
  display: grid; place-items: center; width: 28px; height: 28px; flex: none;
  border-radius: 50%; background: var(--accent); color: #fff; font: 700 .82rem/1 var(--mono);
}
.steps > li > p { color: #9aa3b4; font-size: .96rem; max-width: 60em; }
.steps .code-block { margin-top: 16px; border-color: #2e3547; }

.note {
  margin-top: 34px; padding: 18px 22px; border-radius: var(--radius);
  background: #1b2030; border: 1px solid #2e3547; font-size: .95rem; color: #9aa3b4;
}

/* ---------- logo grid (adopters / consumers) ---------- */
.logo-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 16px; }
.entry {
  display: flex; gap: 14px; align-items: flex-start;
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 18px; color: inherit;
}
.entry:hover { text-decoration: none; border-color: var(--ink-faint); }
.entry-logo {
  width: 40px; height: 40px; flex: none; border-radius: 8px; object-fit: contain;
  background: var(--bg-alt); display: grid; place-items: center;
  font: 700 .95rem/1 var(--sans); color: var(--ink-soft);
}
.entry-name { font-weight: 650; font-size: .97rem; }
.entry-desc { font-size: .86rem; color: var(--ink-faint); margin: 2px 0 0; }
.entry-meta { font: 500 .72rem/1 var(--mono); color: var(--accent); margin-top: 6px; display: block; }

.empty-cta {
  text-align: center; padding: 44px 24px; border: 1px dashed var(--line);
  border-radius: var(--radius); background: #fff;
}
.empty-cta p { color: var(--ink-soft); max-width: 42em; margin: 0 auto 6px; }
.section-alt .empty-cta { background: #fff; }

/* ---------- testimonials ---------- */
.testimonials { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 20px; margin-top: 40px; }
.quote {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 24px; margin: 0;
}
.quote blockquote { margin: 0 0 16px; font-size: 1rem; color: var(--ink); }
.quote blockquote::before { content: "“"; color: var(--accent); font-size: 1.6em; line-height: 0; vertical-align: -.25em; margin-right: 2px; }
.quote figcaption { display: flex; align-items: center; gap: 10px; font-size: .86rem; color: var(--ink-faint); }
.quote img { width: 34px; height: 34px; border-radius: 50%; object-fit: cover; }
.quote-name { font-weight: 650; color: var(--ink); display: block; }

/* ---------- tools ---------- */
.tools-filters { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 28px; }
.chip {
  border: 1px solid var(--line); background: #fff; color: var(--ink-soft);
  border-radius: 999px; padding: 7px 15px; font: 600 .85rem/1 var(--sans); cursor: pointer;
}
.chip:hover { border-color: var(--ink-faint); }
.chip.is-active { background: var(--ink); border-color: var(--ink); color: #fff; }

.tools-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 16px; }
.tool {
  border: 1px solid var(--line); border-radius: var(--radius); padding: 20px;
  background: #fff; display: flex; flex-direction: column; gap: 8px;
}
.tool-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; }
.tool h3 { margin: 0; font-size: 1rem; }
.tool p { margin: 0; font-size: .89rem; color: var(--ink-soft); }
.tool-link { font-size: .85rem; font-weight: 600; margin-top: auto; padding-top: 6px; }
.badge {
  flex: none; font: 600 .68rem/1 var(--sans); letter-spacing: .03em; text-transform: uppercase;
  padding: 5px 8px; border-radius: 999px; white-space: nowrap;
}
.badge-working { background: #e2f5ec; color: var(--ok); }
.badge-wip { background: #fdf0dc; color: var(--warn); }
.badge-proposed { background: var(--bg-alt); color: var(--ink-faint); }

/* ---------- faq ---------- */
.faq details {
  border-bottom: 1px solid var(--line); padding: 18px 0;
}
.faq summary {
  cursor: pointer; font-weight: 650; font-size: 1rem; list-style: none;
  display: flex; justify-content: space-between; gap: 16px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--ink-faint); font-weight: 400; font-size: 1.3rem; line-height: 1; }
.faq details[open] summary::after { content: "–"; }
.faq details p { margin: 12px 0 0; color: var(--ink-soft); font-size: .96rem; max-width: 60em; }

/* ---------- final cta + footer ---------- */
.final-cta {
  padding: 90px 0; text-align: center;
  background: linear-gradient(180deg, var(--bg-alt), #fff);
  border-top: 1px solid var(--line);
}
.final-cta h2 { max-width: 20em; margin-inline: auto; }
.final-cta p { color: var(--ink-soft); max-width: 42em; margin-inline: auto; }

.site-footer { background: var(--bg-dark); color: #8892a6; padding: 40px 0; }
.footer-inner { display: flex; justify-content: space-between; gap: 32px; flex-wrap: wrap; align-items: center; }
.footer-brand { color: #fff; font-weight: 650; margin: 0 0 4px; font-size: .95rem; }
.footer-note { margin: 0; font-size: .85rem; max-width: 46em; }
.footer-links { display: flex; gap: 20px; font-size: .9rem; }
.footer-links a { color: #b6bfd0; }

/* ---------- responsive ---------- */
@media (max-width: 980px) {
  .hero-grid, .spec-detail { grid-template-columns: 1fr; gap: 36px; }
  .cards-3, .cards-2 { grid-template-columns: repeat(2, 1fr); }
  .flow { grid-template-columns: 1fr; }
  .flow-arrow { display: none; }
  .nav { display: none; }
}
@media (max-width: 620px) {
  body { font-size: 16px; }
  .section { padding: 60px 0; }
  .hero { padding: 52px 0 60px; }
  .cards-3, .cards-2 { grid-template-columns: 1fr; }
  .footer-inner { flex-direction: column; align-items: flex-start; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn:hover { transform: none; }
}