/* UCP loyalty reference — shared by the landing page and the technical brief. */
:root {
  --primary: #6e48aa;
  --primary-ink: #4f2f86;
  --secondary: #9d50bb;
  --accent: #4776e6;
  --dark: #1a1a2e;
  --ink: #23233a;
  --muted: #5d6275;
  --line: #e3e0ec;
  --wash: #f6f4fb;
  --bg: #ffffff;
  --public: #1f7a5a;
  --public-wash: #e8f5ef;
  --private: #8a4b08;
  --private-wash: #fdf1e2;
  --stabile: #4f2f86;
  --stabile-wash: #efe9f8;
  --radius: 10px;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: 'Segoe UI', -apple-system, BlinkMacSystemFont, Roboto, Helvetica, Arial, sans-serif;
  font-size: 17px;
  line-height: 1.6;
}
a { color: var(--primary); }
a:hover { color: var(--primary-ink); }
code, pre { font-family: var(--mono); font-size: 0.86em; }
code { background: var(--wash); padding: 0.1em 0.35em; border-radius: 4px; }
img, svg { max-width: 100%; }

.wrap { max-width: 1080px; margin: 0 auto; padding: 0 16px; }
.narrow { max-width: 760px; }

/* Header */
.site-header { border-bottom: 1px solid var(--line); background: #fff; position: sticky; top: 0; z-index: 10; }
.site-header .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 64px; }
.site-header .brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--dark); font-weight: 700; }
.site-header .brand img { height: 32px; width: auto; }
.site-header nav { display: flex; gap: 18px; align-items: center; font-size: 15px; }
.site-header nav a { text-decoration: none; color: var(--muted); }
.site-header nav a:hover { color: var(--primary); }
.site-header nav .btn { color: #fff; }
@media (max-width: 640px) { .site-header nav .hide-sm { display: none; } }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  background: var(--primary); color: #fff; text-decoration: none; border: 0;
  padding: 12px 22px; border-radius: 999px; font-weight: 600; font-size: 16px; cursor: pointer;
  font-family: inherit;
}
.btn:hover { background: var(--primary-ink); color: #fff; }
.btn.small { padding: 8px 16px; font-size: 14px; }
.btn.ghost { background: transparent; color: var(--primary); border: 1.5px solid var(--primary); }
.btn.ghost:hover { background: var(--wash); color: var(--primary-ink); }
.btn:disabled { opacity: 0.6; cursor: default; }

/* Hero */
.hero { padding: 64px 0 40px; background: linear-gradient(180deg, var(--wash), #fff); }
.eyebrow { display: inline-flex; flex-wrap: wrap; gap: 8px; margin-bottom: 18px; }
.chip {
  display: inline-block; font-size: 13px; font-weight: 600; padding: 4px 10px; border-radius: 999px;
  background: #fff; border: 1px solid var(--line); color: var(--muted);
}
.chip.public { background: var(--public-wash); border-color: transparent; color: var(--public); }
.chip.private { background: var(--private-wash); border-color: transparent; color: var(--private); }
.chip.stabile { background: var(--stabile-wash); border-color: transparent; color: var(--stabile); }
.chip.synthetic { background: #fff4c7; border-color: transparent; color: #6b5300; }
h1 { font-size: clamp(32px, 5vw, 50px); line-height: 1.12; color: var(--dark); margin: 0 0 18px; letter-spacing: -0.01em; }
.lede { font-size: clamp(18px, 2.2vw, 21px); color: var(--muted); max-width: 720px; margin: 0 0 28px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }

/* Sections */
section { padding: 56px 0; scroll-margin-top: 64px; }
.explorer, [id] { scroll-margin-top: 80px; }
section + section { border-top: 1px solid var(--line); }
h2 { font-size: clamp(26px, 3.4vw, 34px); line-height: 1.2; color: var(--dark); margin: 0 0 14px; }
h3 { font-size: 20px; color: var(--dark); margin: 0 0 8px; }
.section-kicker { font-size: 13px; font-weight: 700; letter-spacing: 0.08em; text-transform: uppercase; color: var(--primary); margin-bottom: 8px; }
.section-intro { color: var(--muted); max-width: 720px; margin: 0 0 28px; }

.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
@media (max-width: 860px) { .grid-3, .grid-2 { grid-template-columns: 1fr; } }

.card { border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; background: #fff; }
.card p { margin: 0; color: var(--muted); }
.card .icon { font-size: 22px; color: var(--primary); margin-bottom: 10px; display: block; }

.does-not { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px 24px; }
.does-not li { padding-left: 28px; position: relative; }
.does-not li::before { content: "✕"; position: absolute; left: 0; color: #b0364a; font-weight: 700; }
@media (max-width: 640px) { .does-not { grid-template-columns: 1fr; } }

/* Demo explorer */
.explorer { border: 1px solid var(--line); border-radius: 14px; overflow: hidden; background: #fff; }
.explorer-bar { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; justify-content: space-between; padding: 14px 18px; background: var(--wash); border-bottom: 1px solid var(--line); }
.seg { display: inline-flex; border: 1px solid var(--line); border-radius: 999px; overflow: hidden; background: #fff; }
.seg button { border: 0; background: transparent; padding: 7px 14px; font: inherit; font-size: 14px; cursor: pointer; color: var(--muted); }
.seg button[aria-pressed="true"] { background: var(--primary); color: #fff; }
.explorer-body { display: grid; grid-template-columns: 1fr 1fr; }
.explorer-body > div { padding: 20px; min-width: 0; }
.explorer-body > div + div { border-left: 1px solid var(--line); }
@media (max-width: 860px) {
  .explorer-body { grid-template-columns: 1fr; }
  .explorer-body > div + div { border-left: 0; border-top: 1px solid var(--line); }
}
.pane-title { display: flex; align-items: center; gap: 8px; font-weight: 700; margin-bottom: 12px; color: var(--dark); }
.kv { display: grid; grid-template-columns: auto 1fr; gap: 6px 16px; margin: 0 0 14px; font-size: 15px; }
.kv dt { color: var(--muted); }
.kv dd { margin: 0; font-weight: 600; text-align: right; }
.big-number { font-size: 40px; font-weight: 800; color: var(--primary); line-height: 1; }
.big-number small { font-size: 16px; font-weight: 600; color: var(--muted); margin-left: 6px; }
.explain { font-size: 15px; color: var(--muted); margin: 10px 0 0; }
pre.json {
  background: var(--dark); color: #e6e3f3; padding: 14px 16px; border-radius: 8px; overflow-x: auto;
  margin: 0; line-height: 1.5; max-height: 380px;
}
pre.json .k { color: #b9a2ff; }
pre.json .s { color: #9fe0bf; }
pre.json .n { color: #ffd38a; }
pre.json .b { color: #ff9fb4; }

.boundary { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
@media (max-width: 860px) { .boundary { grid-template-columns: 1fr; } }
.boundary .card { border-top: 4px solid var(--line); }
.boundary .public { border-top-color: var(--public); }
.boundary .private { border-top-color: var(--private); }
.boundary .stabile { border-top-color: var(--stabile); }
.boundary ul { margin: 10px 0 0; padding-left: 18px; color: var(--muted); font-size: 15px; }

.diagram { border: 1px solid var(--line); border-radius: 14px; padding: 16px; background: #fff; overflow-x: auto; }
.diagram svg { display: block; min-width: 640px; margin: 0 auto; }

.proof-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 12px; }
.proof-list li { display: flex; gap: 14px; align-items: flex-start; padding: 16px 18px; border: 1px solid var(--line); border-radius: var(--radius); }
.proof-list .tag { flex: none; font-size: 12px; font-weight: 700; padding: 3px 8px; border-radius: 6px; background: var(--public-wash); color: var(--public); margin-top: 3px; }
.proof-list .tag.pending { background: #fff4c7; color: #6b5300; }
.proof-list p { margin: 2px 0 0; color: var(--muted); font-size: 15px; }

/* Pilot form */
.pilot { background: var(--dark); color: #fff; }
.pilot h2, .pilot h3 { color: #fff; }
.pilot .section-intro { color: #c9c6da; }
.pilot-grid { display: grid; grid-template-columns: 1fr 1.3fr; gap: 40px; }
@media (max-width: 860px) { .pilot-grid { grid-template-columns: 1fr; } }
.pilot ul { padding-left: 18px; color: #c9c6da; }
form.pilot-form { background: #fff; color: var(--ink); border-radius: 14px; padding: 24px; display: grid; gap: 14px; }
.field { display: grid; gap: 6px; }
.field label { font-size: 14px; font-weight: 600; }
.field input, .field select, .field textarea {
  font: inherit; font-size: 16px; padding: 10px 12px; border: 1px solid #cfcadf; border-radius: 8px; width: 100%; background: #fff; color: var(--ink);
}
.field textarea { min-height: 88px; resize: vertical; }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
@media (max-width: 560px) { .field-row { grid-template-columns: 1fr; } }
.check { display: flex; gap: 10px; align-items: flex-start; font-size: 14px; color: var(--muted); }
.check input { margin-top: 4px; }
.form-note { font-size: 13px; color: var(--muted); margin: 0; }
.form-status { font-size: 15px; padding: 10px 12px; border-radius: 8px; display: none; }
.form-status.ok { display: block; background: var(--public-wash); color: var(--public); }
.form-status.err { display: block; background: #fbe7ea; color: #9b2335; }

/* Brief */
.brief-meta { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 24px; }
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); }
table { border-collapse: collapse; width: 100%; font-size: 15px; }
th, td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { background: var(--wash); font-size: 13px; text-transform: uppercase; letter-spacing: 0.04em; color: var(--muted); }
tr:last-child td { border-bottom: 0; }
td code { white-space: nowrap; }
.status-released { color: var(--public); font-weight: 600; }
.status-stabile { color: var(--stabile); font-weight: 600; }
.obs { border-left: 4px solid var(--accent); padding: 4px 0 4px 16px; margin: 0 0 18px; }
.obs h3 { font-size: 17px; }
.obs p { margin: 4px 0 0; color: var(--muted); }
.toc { font-size: 15px; columns: 2; padding-left: 18px; }
@media (max-width: 560px) { .toc { columns: 1; } }
.downloads { display: flex; flex-wrap: wrap; gap: 10px; }

footer.site-footer { padding: 32px 0; border-top: 1px solid var(--line); font-size: 14px; color: var(--muted); }
footer.site-footer .wrap { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; }

.noscript { padding: 14px; background: var(--wash); border-radius: 8px; }
.visually-hidden { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }