/* Stello Trace — marketing site
   Zero-dependency static CSS. Light/dark via prefers-color-scheme.
   Tokens use --st-* prefix (Stello Trace), independent from app's --wt-*. */

:root {
  /* palette — paper & ink with the brand coral accent (from brand/logo mark) */
  --st-bg: #faf9f7;
  --st-bg-raised: #ffffff;
  --st-ink: #1c1b1a;
  --st-ink-soft: #57534e;
  --st-ink-faint: #a8a29e;
  --st-line: #e7e5e4;
  --st-accent: #EF6A4B;        /* brand coral — from brand/logo mark */
  --st-accent-strong: #C24425; /* darker coral for text links/kickers (AA on paper bg) */
  --st-accent-ink: #241410;    /* text on coral surfaces */
  --st-accent-soft: #FBE9E3;
  --st-warn-soft: #fdf6e3;

  --st-serif: "Georgia", "Songti SC", "STSong", "Noto Serif SC", serif;
  --st-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --st-mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, monospace;

  --st-radius: 14px;
  --st-radius-sm: 9px;
  --st-maxw: 1080px;
  --st-shadow: 0 1px 2px rgb(28 27 26 / 0.04), 0 8px 24px rgb(28 27 26 / 0.06);
}

@media (prefers-color-scheme: dark) {
  :root {
    --st-bg: #131211;
    --st-bg-raised: #1c1b19;
    --st-ink: #eeece9;
    --st-ink-soft: #b8b3ac;
    --st-ink-faint: #6f6a63;
    --st-line: #2b2926;
    --st-accent: #F07B61;        /* brand coral, dark variant (brand/logo mark-dark) */
    --st-accent-strong: #F59078;
    --st-accent-ink: #241410;
    --st-accent-soft: #33201A;
    --st-warn-soft: #2a2413;
    --st-shadow: 0 1px 2px rgb(0 0 0 / 0.4), 0 10px 30px rgb(0 0 0 / 0.35);
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--st-bg);
  color: var(--st-ink);
  font-family: var(--st-sans);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: var(--st-accent-strong); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
a:focus-visible, button:focus-visible, summary:focus-visible {
  outline: 2px solid var(--st-accent);
  outline-offset: 3px;
  border-radius: 4px;
}

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

/* ---------- header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--st-bg) 86%, transparent);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--st-line);
}
.site-header .wrap {
  display: flex; align-items: center; gap: 20px;
  height: 60px;
}
.brand {
  display: flex; align-items: center; gap: 9px;
  color: var(--st-ink); font-weight: 650; letter-spacing: 0.01em;
}
.brand:hover { text-decoration: none; }
.brand .logo { flex: none; }
.brand .mark { color: var(--st-accent-strong); }
.brand .by {
  font-size: 12px; font-weight: 500; color: var(--st-ink-faint);
  letter-spacing: 0.04em;
}
.nav { margin-left: auto; display: flex; align-items: center; gap: 22px; font-size: 15px; }
.nav a { color: var(--st-ink-soft); }
.nav a:hover { color: var(--st-ink); text-decoration: none; }
.nav .lang { color: var(--st-ink-faint); font-size: 13px; border: 1px solid var(--st-line); padding: 3px 10px; border-radius: 99px; }
.nav .cta {
  color: var(--st-accent-ink); background: var(--st-accent);
  padding: 7px 16px; border-radius: 99px; font-weight: 600;
  white-space: nowrap;
}
.nav .cta:hover { text-decoration: none; filter: brightness(1.06); }
.brand { white-space: nowrap; }
@media (max-width: 720px) {
  .nav .hide-m { display: none; }
  .brand .by { display: none; }
  .nav { gap: 12px; }
}

/* ---------- hero ---------- */
.hero { position: relative; overflow: hidden; }
.hero .wrap { padding-top: 88px; padding-bottom: 72px; position: relative; }
.hero .eyebrow {
  font-size: 13px; letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--st-accent-strong); font-weight: 650; margin: 0 0 18px;
}
.hero h1 {
  font-family: var(--st-serif);
  font-size: clamp(34px, 5.4vw, 56px);
  line-height: 1.18; letter-spacing: -0.01em;
  margin: 0 0 20px; max-width: 21ch;
  text-wrap: balance;
}
.hero .lede {
  font-size: clamp(17px, 2vw, 20px);
  color: var(--st-ink-soft); max-width: 56ch; margin: 0 0 34px;
}
.hero .trace-svg {
  position: absolute; right: -40px; top: 30px; width: 520px; max-width: 55vw;
  opacity: 0.5; pointer-events: none;
}
@media (max-width: 880px) { .hero .trace-svg { display: none; } }

.cta-row { display: flex; flex-wrap: wrap; gap: 14px; align-items: center; }
.btn {
  display: inline-flex; align-items: center; gap: 9px;
  font-weight: 650; font-size: 16px;
  padding: 13px 26px; border-radius: 12px;
  border: 1px solid transparent; cursor: pointer;
}
.btn svg { flex: none; }
.btn-primary { background: var(--st-accent); color: var(--st-accent-ink); box-shadow: var(--st-shadow); }
.btn-primary:hover { text-decoration: none; filter: brightness(1.06); transform: translateY(-1px); }
.btn-ghost { border-color: var(--st-line); color: var(--st-ink); background: var(--st-bg-raised); }
.btn-ghost:hover { text-decoration: none; border-color: var(--st-ink-faint); }
.btn { transition: transform 0.15s ease, filter 0.15s ease, border-color 0.15s ease; }

.proof {
  display: flex; flex-wrap: wrap; gap: 10px 22px;
  margin-top: 26px; padding: 0; list-style: none;
  font-size: 13.5px; color: var(--st-ink-faint);
}
.proof li { display: flex; align-items: center; gap: 7px; }
.proof svg { color: var(--st-accent); flex: none; }

/* ---------- sections ---------- */
section { padding: 72px 0; }
section.alt { background: var(--st-bg-raised); border-block: 1px solid var(--st-line); }
.kicker {
  font-size: 13px; letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--st-accent-strong); font-weight: 650; margin: 0 0 12px;
}
h2 {
  font-family: var(--st-serif);
  font-size: clamp(26px, 3.4vw, 36px);
  line-height: 1.25; margin: 0 0 14px; letter-spacing: -0.01em;
  text-wrap: balance;
}
.sub { color: var(--st-ink-soft); max-width: 62ch; margin: 0 0 40px; }

/* steps */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
@media (max-width: 880px) { .steps { grid-template-columns: 1fr; } }
.step {
  background: var(--st-bg-raised); border: 1px solid var(--st-line);
  border-radius: var(--st-radius); padding: 26px 24px;
}
section.alt .step { background: var(--st-bg); }
.step .num {
  font-family: var(--st-mono); font-size: 13px; color: var(--st-accent-strong);
  display: inline-block; margin-bottom: 14px;
  border: 1px solid var(--st-line); border-radius: 99px; padding: 2px 10px;
}
.step h3 { margin: 0 0 8px; font-size: 18.5px; }
.step p { margin: 0; color: var(--st-ink-soft); font-size: 15.5px; }

/* feature grid */
.grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 22px; }
@media (max-width: 880px) { .grid { grid-template-columns: 1fr; } }
.card {
  background: var(--st-bg-raised); border: 1px solid var(--st-line);
  border-radius: var(--st-radius); padding: 28px 26px;
  box-shadow: var(--st-shadow);
}
.card .icon {
  width: 40px; height: 40px; border-radius: 10px;
  background: var(--st-accent-soft); color: var(--st-accent-strong);
  display: grid; place-items: center; margin-bottom: 16px;
}
.card h3 { margin: 0 0 8px; font-size: 19px; }
.card p { margin: 0; color: var(--st-ink-soft); font-size: 15.5px; }

/* report mock */
.mock {
  border: 1px solid var(--st-line); border-radius: var(--st-radius);
  background: var(--st-bg-raised); box-shadow: var(--st-shadow);
  max-width: 620px; margin: 44px auto 0; overflow: hidden;
}
.mock .bar {
  display: flex; align-items: center; gap: 8px;
  padding: 10px 16px; border-bottom: 1px solid var(--st-line);
  font-family: var(--st-mono); font-size: 12px; color: var(--st-ink-faint);
}
.mock .dot { width: 10px; height: 10px; border-radius: 50%; background: var(--st-line); }
.mock .dot:first-child { background: #f87171; }
.mock .dot:nth-child(2) { background: #fbbf24; }
.mock .dot:nth-child(3) { background: #34d399; }
.mock .body { padding: 24px 28px 28px; }
.mock .date {
  font-family: var(--st-mono); font-size: 12.5px; color: var(--st-ink-faint);
  margin-bottom: 12px;
}
.mock p {
  font-family: var(--st-serif); font-size: 16.5px; line-height: 1.75; margin: 0 0 12px;
}
.mock .tag-row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.mock .tag {
  font-size: 12.5px; font-family: var(--st-mono);
  color: var(--st-ink-soft); background: var(--st-accent-soft);
  border-radius: 6px; padding: 3px 9px;
}
.mock .note { font-size: 12px; color: var(--st-ink-faint); text-align: right; margin: 10px 16px; }

/* privacy ledger */
.ledger { border: 1px solid var(--st-line); border-radius: var(--st-radius); overflow: hidden; margin-top: 8px; }
.ledger table { width: 100%; border-collapse: collapse; font-size: 15px; }
.ledger th, .ledger td { text-align: left; padding: 13px 18px; border-bottom: 1px solid var(--st-line); vertical-align: top; }
.ledger tr:last-child td { border-bottom: none; }
.ledger th { background: var(--st-bg-raised); font-size: 13.5px; color: var(--st-ink-soft); font-weight: 600; }
.ledger td:first-child { font-weight: 600; white-space: nowrap; }
.ledger .ok { color: var(--st-accent-strong); font-weight: 650; }
.ledger td { color: var(--st-ink-soft); }
.ledger td:first-child { color: var(--st-ink); }
@media (max-width: 720px) {
  .ledger { overflow-x: auto; }
  .ledger table { min-width: 560px; }
}

/* org band */
.org {
  border: 1px solid var(--st-line);
  border-radius: calc(var(--st-radius) + 4px);
  padding: 44px 40px;
  background:
    radial-gradient(600px 240px at 90% -20%, var(--st-accent-soft), transparent 70%),
    var(--st-bg-raised);
  display: grid; grid-template-columns: 1.5fr 1fr; gap: 32px; align-items: center;
}
@media (max-width: 880px) { .org { grid-template-columns: 1fr; padding: 32px 26px; } }
.org h2 { margin-bottom: 10px; }
.org p { color: var(--st-ink-soft); margin: 0 0 6px; }
.org .side { justify-self: end; text-align: right; }
@media (max-width: 880px) { .org .side { justify-self: start; text-align: left; } }
.org .side .small { display: block; margin-top: 10px; font-size: 13px; color: var(--st-ink-faint); }

/* faq */
.faq { max-width: 760px; }
.faq details {
  border-bottom: 1px solid var(--st-line);
  padding: 4px 0;
}
.faq summary {
  cursor: pointer; list-style: none;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  font-weight: 600; font-size: 17px; padding: 16px 4px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; font-family: var(--st-mono); color: var(--st-ink-faint);
  font-size: 20px; transition: transform 0.2s ease;
}
.faq details[open] summary::after { transform: rotate(45deg); }
.faq details p { margin: 0 4px 18px; color: var(--st-ink-soft); font-size: 15.5px; max-width: 66ch; }

/* download */
.download { text-align: center; }
.download h2 { margin-bottom: 10px; }
.download .sub { margin-inline: auto; }
.download .fine { font-size: 13px; color: var(--st-ink-faint); margin-top: 18px; }
.download .fine a { color: var(--st-ink-faint); text-decoration: underline; }

/* footer */
footer {
  border-top: 1px solid var(--st-line);
  padding: 36px 0 48px; font-size: 14px; color: var(--st-ink-faint);
}
footer .wrap { display: flex; flex-wrap: wrap; gap: 14px 28px; align-items: center; }
footer a { color: var(--st-ink-soft); }
footer .spacer { flex: 1; }

/* prose (privacy page) */
.prose { max-width: 760px; padding: 56px 0 80px; }
.prose h1 { font-family: var(--st-serif); font-size: clamp(30px, 4vw, 40px); line-height: 1.2; margin: 0 0 8px; }
.prose .updated { font-family: var(--st-mono); font-size: 13px; color: var(--st-ink-faint); margin-bottom: 36px; }
.prose h2 { font-size: 23px; margin: 40px 0 12px; }
.prose p, .prose li { color: var(--st-ink-soft); }
.prose li { margin-bottom: 6px; }
.prose strong { color: var(--st-ink); }
.prose code {
  font-family: var(--st-mono); font-size: 0.88em;
  background: var(--st-bg-raised); border: 1px solid var(--st-line);
  padding: 1px 6px; border-radius: 6px;
}

/* responsive overrides — keep last so they win the cascade */
@media (max-width: 720px) {
  section { padding: 52px 0; }
  .hero .wrap { padding-top: 36px; padding-bottom: 44px; }
  .org { padding: 30px 22px; }
  .mock .body { padding: 20px 18px 22px; }
}