/* Deerlight Labs brand site.
   参考：refs/amie（窄栏长页面、三层浅投影、灰色正文、松行高）、refs/cartesia（衬线标题 + 无衬线正文、页脚）。
   One accent: the effect sites' pink, deepened to #E0115F so white text on it passes AA. */

:root {
  --bg: #ffffff;
  --bg-subtle: #f7f8fa;
  --text: #171717;
  --text-2: #5c5c5c;
  --text-3: #8a8a8a;
  --line: rgba(0, 0, 0, 0.08);
  --brand: #e0115f;
  --brand-press: #c20d51;
  --brand-soft: #fde7ef;
  --shadow-card: 0 0 0 1px rgba(0, 0, 0, 0.06), 0 1px 1px -0.5px rgba(0, 0, 0, 0.06), 0 3px 3px -1.5px rgba(0, 0, 0, 0.06);
  --serif: 'Instrument Serif', Georgia, 'Times New Roman', serif;
  --sans: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  --mono: 'IBM Plex Mono', ui-monospace, 'SFMono-Regular', Menlo, monospace;
  --ease: cubic-bezier(0.2, 0.7, 0.2, 1);
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; -webkit-tap-highlight-color: transparent; scroll-padding-top: 88px; }
body { margin: 0; background: var(--bg); color: var(--text); font: 400 17px/1.7 var(--sans); }
a { color: var(--brand); text-underline-offset: 3px; text-decoration-thickness: 1px; }
a:hover { color: var(--brand-press); }
:focus-visible { outline: 2px solid var(--brand); outline-offset: 3px; border-radius: 4px; }

/* Header */
.top { position: sticky; top: 0; z-index: 10; background: rgba(255, 255, 255, 0.92); backdrop-filter: saturate(1.4) blur(10px); border-bottom: 1px solid var(--line); }
.top-in { max-width: 1120px; margin: 0 auto; height: 64px; padding: 0 20px; display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--text); text-decoration: none; font: 600 17px/1 var(--sans); letter-spacing: -0.01em; white-space: nowrap; }
.brand img { width: 28px; height: 28px; display: block; }
.nav { display: flex; gap: 4px; }
.nav a { color: var(--text-2); text-decoration: none; font-size: 15px; padding: 8px 12px; border-radius: 8px; transition: background-color 120ms var(--ease), color 120ms var(--ease); }
.nav a:hover { background: var(--bg-subtle); color: var(--text); }
.nav a:active { transform: scale(0.97); }
.nav a[aria-current='page'] { color: var(--text); }

/* Page grid: 720px column, rails on wide screens */
.page { max-width: 1680px; margin: 0 auto; padding: 0 20px; display: grid; grid-template-columns: minmax(0, 720px); justify-content: center; column-gap: 64px; }
.rail { display: none; }
@media (min-width: 1600px) {
  .page { grid-template-columns: 280px minmax(0, 720px) 280px; }
  .page.single { grid-template-columns: minmax(0, 960px); }
  .rail { display: block; padding-top: 120px; }
  .rail-in { position: sticky; top: 104px; }
}

/* Hero */
.hero { padding: 96px 0 56px; }
.eyebrow { font: 500 12px/1.4 var(--mono); letter-spacing: 0.06em; text-transform: uppercase; color: var(--text-3); margin: 0 0 20px; }
h1 { font: 400 64px/1.04 var(--serif); letter-spacing: -0.02em; margin: 0; }
h1 .dim { color: var(--text-3); }
.lead { font-size: 20px; line-height: 1.55; color: var(--text-2); margin: 24px 0 0; max-width: 620px; }

/* Sections */
section { padding: 48px 0; border-top: 1px solid var(--line); }
h2 { font: 400 36px/1.15 var(--serif); letter-spacing: -0.01em; margin: 0 0 16px; }
h3 { font: 600 18px/1.35 var(--sans); margin: 28px 0 8px; }
p { margin: 0 0 16px; color: var(--text-2); }
p strong, li strong { color: var(--text); font-weight: 600; }
ul { margin: 0 0 16px; padding-left: 20px; color: var(--text-2); }
li { margin: 6px 0; }
li::marker { color: var(--text-3); }

/* Steps: one column, numbered, not a card grid */
.steps { list-style: none; padding: 0; margin: 24px 0 0; counter-reset: step; }
.steps li { counter-increment: step; display: grid; grid-template-columns: 44px 1fr; gap: 4px 12px; padding: 16px 0; border-bottom: 1px solid var(--line); margin: 0; }
.steps li:last-child { border-bottom: 0; }
.steps li::before { content: '0' counter(step); grid-row: span 2; font: 500 13px/28px var(--mono); color: var(--brand); }
.steps b { color: var(--text); font-weight: 600; }
.steps span { color: var(--text-2); }

/* The Google data panel: the part reviewers and careful users look for */
.panel { background: var(--bg-subtle); border-radius: 16px; padding: 24px; margin: 24px 0 8px; }
.panel dl { margin: 0; display: grid; grid-template-columns: 160px 1fr; gap: 12px 20px; }
.panel dt { font: 500 12px/1.6 var(--mono); letter-spacing: 0.06em; text-transform: uppercase; color: var(--text-3); padding-top: 2px; }
.panel dd { margin: 0; color: var(--text); font-size: 16px; line-height: 1.6; }

/* Contact card (rail and inline) */
.card { background: var(--bg); border-radius: 12px; box-shadow: var(--shadow-card); padding: 20px; }
.card .label { font: 500 12px/1.4 var(--mono); letter-spacing: 0.06em; text-transform: uppercase; color: var(--text-3); margin: 0 0 8px; }
.card p { font-size: 15px; margin: 0 0 12px; }
.card p:last-child { margin: 0; }
.btn { display: inline-flex; align-items: center; justify-content: center; height: 44px; padding: 0 18px; border-radius: 12px; background: var(--brand); color: #fff; font: 600 15px/1 var(--sans); text-decoration: none; transition: background-color 120ms var(--ease), transform 120ms var(--ease); }
.btn:hover { background: var(--brand-press); color: #fff; }
.btn:active { transform: scale(0.97); }

/* Rail table of contents */
.toc { list-style: none; padding: 0; margin: 0; border-left: 1px solid var(--line); }
.toc li { margin: 0; }
.toc a { display: block; padding: 6px 0 6px 16px; margin-left: -1px; border-left: 1px solid transparent; color: var(--text-2); text-decoration: none; font-size: 14px; line-height: 1.5; }
.toc a:hover { color: var(--text); border-left-color: var(--text-3); }

/* Legal pages */
.doc { padding: 80px 0 32px; }
.doc h1 { font-size: 52px; }
.doc .updated { font: 500 12px/1.4 var(--mono); letter-spacing: 0.06em; text-transform: uppercase; color: var(--text-3); margin: 16px 0 0; }
.doc section { padding: 32px 0; }
.doc h2 { font-size: 28px; }

/* Footer */
.foot { border-top: 1px solid var(--line); margin-top: 48px; }
.foot-in { max-width: 1120px; margin: 0 auto; padding: 32px 20px 48px; display: flex; flex-wrap: wrap; gap: 12px 24px; align-items: center; justify-content: space-between; color: var(--text-3); font-size: 14px; }
.foot nav { display: flex; flex-wrap: wrap; gap: 4px 20px; }
.foot a { color: var(--text-2); text-decoration: none; }
.foot a:hover { color: var(--text); }
.only-narrow { display: block; }
@media (min-width: 1600px) { .only-narrow { display: none; } }

@media (max-width: 767px) {
  body { font-size: 16px; }
  .nav a { padding: 8px 8px; font-size: 14px; }
  .nav .hide-sm { display: none; }
  .hero { padding: 56px 0 40px; }
  h1 { font-size: 44px; }
  .doc { padding: 48px 0 24px; }
  .doc h1 { font-size: 40px; }
  h2 { font-size: 30px; }
  .lead { font-size: 18px; }
  .panel dl { grid-template-columns: 1fr; gap: 4px; }
  .panel dd { margin-bottom: 12px; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}