:root {
  color-scheme: light;
  --ink: #171717;
  --muted: #68645d;
  --paper: #fffdf8;
  --surface: #ffffff;
  --accent: #ffb000;
  --accent-dark: #9a5f00;
  --line: #e8e1d5;
  --shadow: 0 20px 60px rgb(34 28 17 / 9%);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-synthesis: none;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 90% 0, rgb(255 176 0 / 18%), transparent 28rem),
    var(--paper);
  line-height: 1.65;
}
a { color: inherit; }
img { display: block; max-width: 100%; }
button, a { -webkit-tap-highlight-color: transparent; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }
[data-lang="zh"] { display: none; }
html[data-language="zh"] [data-lang="zh"] { display: revert; }
html[data-language="zh"] [data-lang="en"] { display: none; }

.skip-link {
  position: fixed;
  top: 1rem;
  left: 1rem;
  z-index: 10;
  padding: .65rem 1rem;
  border-radius: .5rem;
  background: var(--ink);
  color: white;
  transform: translateY(-180%);
}
.skip-link:focus { transform: translateY(0); }
.container { width: min(1120px, calc(100% - 2rem)); margin-inline: auto; }
.site-header { border-bottom: 1px solid rgb(232 225 213 / 80%); backdrop-filter: blur(16px); }
.header-inner { min-height: 76px; display: flex; align-items: center; gap: 2rem; }
.brand { margin-right: auto; text-decoration: none; }
.brand img { width: 168px; height: auto; }
.site-nav { display: flex; align-items: center; gap: 1.25rem; }
.site-nav a { color: var(--muted); font-weight: 650; text-decoration: none; }
.site-nav a[aria-current="page"], .site-nav a:hover { color: var(--ink); }
.language-switcher { display: flex; gap: .25rem; padding: .25rem; border: 1px solid var(--line); border-radius: 999px; background: white; }
.language-switcher button { border: 0; border-radius: 999px; padding: .4rem .65rem; color: var(--muted); background: transparent; cursor: pointer; }
.language-switcher button[aria-pressed="true"] { color: var(--ink); background: var(--accent); }

main { min-height: calc(100vh - 230px); }
.hero { padding: clamp(4rem, 10vw, 8rem) 0 5rem; }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(280px, .8fr); align-items: center; gap: 4rem; }
.eyebrow { margin: 0 0 .8rem; color: var(--accent-dark); font-size: .8rem; font-weight: 800; letter-spacing: .12em; text-transform: uppercase; }
h1, h2, h3 { line-height: 1.15; letter-spacing: -.035em; }
h1 { max-width: 780px; margin: 0 0 1.25rem; font-size: clamp(2.7rem, 7vw, 5.4rem); }
h2 { margin: 0 0 1rem; font-size: clamp(2rem, 4vw, 3.2rem); }
h3 { margin: 0 0 .65rem; font-size: 1.25rem; }
.lead { max-width: 720px; margin: 0 0 2rem; color: var(--muted); font-size: clamp(1.05rem, 2vw, 1.25rem); }
.actions { display: flex; flex-wrap: wrap; gap: .8rem; }
.button { display: inline-flex; min-height: 48px; align-items: center; justify-content: center; padding: .7rem 1.1rem; border: 1px solid var(--ink); border-radius: .7rem; background: var(--ink); color: white; font-weight: 750; text-decoration: none; }
.button.secondary { background: transparent; color: var(--ink); }
.button[aria-disabled="true"] { border-color: var(--line); background: #eeeae2; color: #756f66; cursor: not-allowed; }
.hero-card { position: relative; overflow: hidden; padding: 2rem; border: 1px solid var(--line); border-radius: 1.5rem; background: var(--surface); box-shadow: var(--shadow); }
.hero-card::before { content: "ABC"; position: absolute; right: -1rem; bottom: -2.8rem; color: rgb(255 176 0 / 16%); font-size: 7rem; font-weight: 900; }
.sample-line { position: relative; margin: .8rem 0; padding: .8rem 1rem; border-radius: .7rem; background: #f7f5f0; }
.sample-line strong { box-shadow: inset 0 -.45em var(--accent); }

.section { padding: 5rem 0; }
.section.alt { border-block: 1px solid var(--line); background: rgb(255 255 255 / 68%); }
.section-heading { max-width: 720px; margin-bottom: 2rem; }
.section-heading p { color: var(--muted); }
.card-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1rem; }
.card { padding: 1.5rem; border: 1px solid var(--line); border-radius: 1rem; background: var(--surface); }
.card p { margin-bottom: 0; color: var(--muted); }
.page-hero { padding: 4rem 0 2rem; }
.page-hero h1 { font-size: clamp(2.6rem, 6vw, 4.4rem); }
.content-layout { display: grid; grid-template-columns: minmax(0, 1fr) 280px; gap: 4rem; padding-bottom: 5rem; }
.legal-copy { max-width: 800px; }
.legal-copy section { margin: 0 0 2.5rem; scroll-margin-top: 2rem; }
.legal-copy p, .legal-copy li { color: #48443e; }
.legal-copy a, .contact-link { color: #755000; text-underline-offset: .2em; }
.toc { align-self: start; position: sticky; top: 1rem; padding: 1.25rem; border: 1px solid var(--line); border-radius: 1rem; background: white; }
.toc strong { display: block; margin-bottom: .6rem; }
.toc a { display: block; padding: .25rem 0; color: var(--muted); text-decoration: none; }
.faq { max-width: 820px; }
.faq details { margin-bottom: .8rem; padding: 1rem 1.2rem; border: 1px solid var(--line); border-radius: .8rem; background: white; }
.faq summary { cursor: pointer; font-weight: 750; }
.notice { padding: 1rem 1.2rem; border-left: 4px solid var(--accent); background: #fff7df; }
.meta { color: var(--muted); font-size: .94rem; }

.site-footer { padding: 2.5rem 0; border-top: 1px solid var(--line); color: var(--muted); }
.footer-inner { display: flex; justify-content: space-between; gap: 2rem; }
.footer-links { display: flex; flex-wrap: wrap; gap: 1rem; }

@media (max-width: 800px) {
  .header-inner { flex-wrap: wrap; gap: .8rem; padding: 1rem 0; }
  .site-nav { order: 3; width: 100%; overflow-x: auto; gap: 1rem; }
  .hero-grid, .content-layout { grid-template-columns: 1fr; gap: 2rem; }
  .card-grid { grid-template-columns: 1fr 1fr; }
  .toc { position: static; order: -1; }
}

@media (max-width: 520px) {
  .container { width: min(100% - 1.25rem, 1120px); }
  .brand img { width: 142px; }
  .card-grid { grid-template-columns: 1fr; }
  .footer-inner { flex-direction: column; }
  .hero { padding-top: 3.5rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}