/* ==========================================================================
   [T04] 瑞士网格 · Swiss Grid — 官网模板库
   国际主义排版：黑白高对比 + 单一蓝强调 + 全直角 + 边框代阴影 + 巨型标题
   字体：Space Grotesk / Noto Sans SC · 圆角 0px · 浅色内页头 + 黑色 CTA/页脚
   契约：类名与骨架完全一致，复制为本站 css/style.css 即可使用
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;500;600;700&family=Noto+Sans+SC:wght@400;500;700&display=swap');

/* ---------- 1. Design tokens ---------- */
:root {
  --bg: #ffffff;
  --bg-soft: #f5f5f5;
  --ink: #0a0a0a;
  --muted: #525252;
  --line: #d4d4d4;

  --accent: #2563eb;
  --accent-strong: #1d4ed8;
  --accent-soft: #dbeafe;

  --danger: #b91c1c;

  --radius: 0px;
  --radius-sm: 0px;

  --font-sans: "Space Grotesk", "Noto Sans SC", "PingFang SC", "Microsoft YaHei",
    ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;

  --logo-bg: #0a0a0a;
  --logo-accent: #2563eb;

  --header-h: 72px;
  --maxw: 1160px;
}

/* ---------- 2. Reset & base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.65;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5 {
  margin: 0 0 0.5em; line-height: 1.08; font-weight: 700;
  color: var(--ink); letter-spacing: -0.03em; text-wrap: balance;
}
h1 { font-size: clamp(2.4rem, 6.5vw, 4.5rem); }
h2 { font-size: clamp(1.8rem, 4vw, 2.9rem); }
h3 { font-size: clamp(1.1rem, 2vw, 1.35rem); }

p { margin: 0 0 1rem; }

a { color: var(--accent-strong); text-decoration: none; transition: color 0.18s ease; }
a:hover { color: var(--ink); }

img, svg { display: block; max-width: 100%; }
ul, ol { margin: 0 0 1rem; padding-left: 1.25rem; }
li { margin-bottom: 0.35rem; }
button, input, select, textarea { font: inherit; }

:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; }
::selection { background: var(--accent); color: #fff; }

h1 em, h2 em { font-style: normal; color: var(--accent); letter-spacing: -0.03em; }

/* ---------- 3. Layout helpers ---------- */
.container { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: 20px; }

.section { padding: 84px 0; }
.section--soft { background: var(--bg-soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section--navy { background: #0a0a0a; color: #e5e5e5; }
.section--navy h2, .section--navy h3 { color: #fff; }

.section-head { max-width: 720px; margin: 0 auto 44px; text-align: center; }

.eyebrow {
  display: inline-block; font-size: 0.75rem; font-weight: 700;
  letter-spacing: 0.22em; text-transform: uppercase;
  color: var(--accent-strong); margin-bottom: 10px;
}
.eyebrow--light { color: #7fafef; }

.lede { font-size: 1.08rem; color: var(--muted); }
.text-muted { color: var(--muted); }

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

/* ---------- 4. Buttons ---------- */
.button {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 13px 24px; border-radius: 0; border: 2px solid var(--ink);
  font-weight: 600; font-size: 0.98rem; line-height: 1;
  cursor: pointer; text-align: center;
  transition: background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease;
}
.button:active { transform: none; }
.button span { font-size: 1.05em; }

.button--primary { background: var(--accent); color: #fff; border-color: var(--accent); }
.button--primary:hover { background: var(--accent-strong); border-color: var(--accent-strong); color: #fff; }

.button--secondary { background: transparent; color: var(--ink); border-color: var(--ink); }
.button--secondary:hover { background: var(--ink); color: #fff; }

.button--ghost { background: transparent; color: var(--ink); border-color: var(--ink); }
.button--ghost:hover { background: var(--ink); color: #fff; }

.button--lg { padding: 16px 30px; font-size: 1.05rem; }
.button--block { width: 100%; }

/* ---------- 5. Header / navigation ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: var(--bg);
  border-bottom: 2px solid var(--ink);
}
.site-header__inner {
  display: flex; align-items: center; justify-content: space-between;
  gap: 14px; height: var(--header-h);
}

.brand {
  display: inline-flex; align-items: center; gap: 10px;
  font-weight: 700; font-size: 0.95rem; letter-spacing: -0.01em;
  color: var(--ink); min-width: 0;
}
.brand:hover { color: var(--ink); }
.brand__mark { width: 34px; height: 34px; flex: 0 0 auto; }
.brand > span:last-child { line-height: 1.2; }

.site-nav { display: flex; align-items: center; gap: 4px; }
.site-nav__link {
  display: block; padding: 9px 14px; border-radius: 0;
  color: var(--muted); font-weight: 500; font-size: 0.95rem; white-space: nowrap;
  text-transform: uppercase; letter-spacing: 0.04em;
  transition: color 0.15s ease, background-color 0.15s ease;
}
.site-nav__link:hover { color: var(--ink); background: var(--bg-soft); }
.site-nav__link[aria-current="page"] { color: #fff; background: var(--ink); font-weight: 600; }

.nav-cta { margin-left: 10px; }
.header-actions { display: flex; align-items: center; gap: 8px; }

.lang-toggle {
  display: inline-flex; align-items: center;
  padding: 7px 14px; border: 2px solid var(--ink); border-radius: 0;
  background: var(--bg); color: var(--ink);
  font-size: 0.8rem; font-weight: 700; cursor: pointer; white-space: nowrap;
  transition: background-color 0.18s ease, color 0.18s ease;
}
.lang-toggle:hover { background: var(--ink); color: #fff; }

.nav-toggle {
  display: none; width: 44px; height: 44px;
  align-items: center; justify-content: center;
  border: 2px solid var(--ink); border-radius: 0;
  background: var(--bg); cursor: pointer; color: var(--ink);
}
.nav-toggle span, .nav-toggle span::before, .nav-toggle span::after {
  display: block; width: 20px; height: 2px;
  background: currentColor; border-radius: 0; position: relative;
  transition: transform 0.2s ease, opacity 0.2s ease;
}
.nav-toggle span::before, .nav-toggle span::after { content: ""; position: absolute; left: 0; }
.nav-toggle span::before { top: -6px; }
.nav-toggle span::after { top: 6px; }
.nav-toggle[aria-expanded="true"] span { background: transparent; }
.nav-toggle[aria-expanded="true"] span::before { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span::after { transform: translateY(-6px) rotate(-45deg); }

/* ---------- 6. Hero ---------- */
.hero {
  position: relative;
  background: var(--bg);
  color: var(--ink);
  padding: 88px 0 96px;
  border-bottom: 1px solid var(--line);
}

.hero__grid { display: grid; grid-template-columns: 1fr; gap: 48px; align-items: center; }
.hero h1 { color: var(--ink); margin-bottom: 0.45em; }
.hero .eyebrow { color: var(--accent-strong); }
.hero__lede { font-size: 1.13rem; color: var(--muted); max-width: 34em; }
.hero__cta { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 28px; }
.hero__meta { display: flex; flex-wrap: wrap; gap: 22px; margin-top: 34px; font-size: 0.9rem; color: var(--muted); }
.hero__meta span { display: inline-flex; align-items: center; gap: 7px; }
.hero__meta svg { color: var(--accent-strong); flex: 0 0 auto; }

.hero__visual { position: relative; }

.hero-card {
  background: var(--bg);
  border: 2px solid var(--ink);
  padding: 22px;
}
.hero-card__window {
  border: 1.5px solid var(--ink); overflow: hidden;
  background: var(--bg);
}
.hero-card__titlebar {
  display: flex; align-items: center; gap: 8px;
  padding: 11px 14px; background: var(--bg-soft);
  border-bottom: 1.5px solid var(--ink);
}
.hero-card__dot { width: 10px; height: 10px; border-radius: 0; background: var(--line); }
.hero-card__dot--a { background: var(--ink); }
.hero-card__dot--b { background: var(--muted); }
.hero-card__dot--c { background: var(--accent); }
.hero-card__app { margin-left: 6px; font-size: 0.74rem; font-weight: 600; color: var(--muted); text-transform: uppercase; letter-spacing: 0.08em; }

.hero-card__body { padding: 20px 18px 16px; }

.wf__track { position: relative; display: flex; justify-content: space-between; margin: 4px 6px 10px; }
.wf__line { position: absolute; top: 11px; left: 12px; right: 12px; height: 2px; background: var(--line); }
.wf__node {
  width: 24px; height: 24px; border-radius: 0;
  border: 2px solid var(--ink); background: var(--bg);
  color: var(--muted); display: grid; place-items: center; z-index: 1;
  font-size: 11px; font-weight: 600;
}
.wf__node--done, .wf__node--current { background: var(--accent); border-color: var(--ink); color: #fff; }
.wf__node--current { box-shadow: 0 0 0 4px var(--accent-soft); }

.wf__labels { display: flex; justify-content: space-between; color: var(--muted); font-size: 0.66rem; text-transform: uppercase; letter-spacing: 0.06em; }

.wf__task {
  display: flex; align-items: center; gap: 10px;
  border-top: 1.5px solid var(--ink);
  margin-top: 16px; padding-top: 14px;
  font-size: 0.78rem; color: var(--ink);
}
.wf__task + .wf__task { margin-top: 12px; }
.wf__task strong { margin-left: auto; font-size: 0.66rem; font-weight: 600; color: var(--accent-strong); text-transform: uppercase; }
.wf__avatar {
  width: 24px; height: 24px; border-radius: 0;
  display: grid; place-items: center;
  font-size: 0.7rem; font-weight: 700; flex: 0 0 auto;
}
.wf__avatar--a { background: var(--ink); color: #fff; }
.wf__avatar--b { background: var(--accent); color: #fff; }

.hero-card__stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin-top: 18px; }
.stat {
  background: var(--bg); border: 1.5px solid var(--ink);
  padding: 14px 10px; text-align: center;
}
.stat__num { display: block; font-size: 1.4rem; font-weight: 700; color: var(--ink); }
.stat__label { font-size: 0.72rem; color: var(--muted); }

/* ---------- 7. Cards & grids ---------- */
.grid { display: grid; grid-template-columns: 1fr; gap: 20px; }
.grid--2 { grid-template-columns: 1fr; }
.grid--3 { grid-template-columns: 1fr; }

.card {
  background: var(--bg);
  border: 1.5px solid var(--ink);
  border-radius: 0; padding: 26px;
  transition: background-color 0.18s ease;
}
.card:hover { background: var(--bg-soft); }
.card h3 { margin-bottom: 0.4em; }
.card p { color: var(--muted); }
.card p:last-child { margin-bottom: 0; }

.icon-badge {
  display: inline-grid; place-items: center;
  width: 52px; height: 52px; border-radius: 0;
  background: var(--accent-soft); color: var(--accent-strong);
  margin-bottom: 16px;
}

/* ---------- 8. Check list ---------- */
.check-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 14px; }
.check-list li { display: flex; gap: 14px; align-items: flex-start; margin: 0; }
.check-list .check { flex: 0 0 auto; margin-top: 3px; color: var(--accent-strong); }
.check-list strong { display: block; color: var(--ink); margin-bottom: 2px; }
.check-list span:not(.check) { color: var(--muted); }

/* ---------- 9. Panel ---------- */
.why-wrap { display: grid; grid-template-columns: 1fr; gap: 40px; align-items: center; }

.panel {
  background: var(--ink);
  border: 2px solid var(--ink);
  padding: 34px;
  color: #e5e5e5;
}
.panel h3 { color: #fff; }
.panel p { color: #a3a3a3; }

.panel__steps { margin: 18px 0 6px; }
.panel__step {
  display: flex; gap: 14px; align-items: flex-start;
  padding: 11px 0; border-bottom: 1px solid #404040;
}
.panel__step:last-child { border-bottom: 0; }
.panel__num {
  flex: 0 0 auto; width: 30px; height: 30px; border-radius: 0;
  display: grid; place-items: center;
  border: 1.5px solid #fff; color: #fff;
  font-weight: 700; font-size: 0.85rem;
}
.panel__step strong { display: block; color: #fff; font-size: 0.95rem; }
.panel__step small { color: #a3a3a3; font-size: 0.8rem; line-height: 1.5; display: block; }

.chips { display: inline-flex; flex-wrap: wrap; gap: 8px; margin-top: 10px; }
.chip {
  display: inline-block; padding: 6px 13px; border-radius: 0;
  background: transparent; border: 1.5px solid #fff;
  font-size: 0.78rem; font-weight: 600; color: #fff; text-transform: uppercase; letter-spacing: 0.06em;
}

/* ---------- 10. Process ---------- */
.process { display: grid; grid-template-columns: 1fr; gap: 16px; }
.process__step { display: flex; gap: 16px; align-items: flex-start; }
.process__num {
  flex: 0 0 auto; width: 40px; height: 40px; border-radius: 0;
  display: grid; place-items: center;
  background: var(--ink); color: #fff;
  font-weight: 700; font-size: 1rem;
}
.process__step h3 { margin-bottom: 0.2em; }
.process__step p { color: var(--muted); margin: 0; }

/* ---------- 11. Contact ---------- */
.contact-grid { display: grid; grid-template-columns: 1fr; gap: 28px; }
.contact-card { background: var(--bg); border: 1.5px solid var(--ink); padding: 26px; }
.contact-item { display: flex; gap: 14px; align-items: flex-start; padding: 14px 0; border-bottom: 1px solid var(--line); }
.contact-item:last-child { border-bottom: 0; }
.contact-item .icon-badge { width: 42px; height: 42px; margin: 0; }
.contact-item h3 { font-size: 1rem; margin: 0 0 2px; }
.contact-item p { margin: 0; color: var(--muted); }
.contact-item a { color: var(--accent-strong); font-weight: 500; }

/* ---------- 12. Forms ---------- */
.form-card { background: var(--bg); border: 1.5px solid var(--ink); padding: 28px; }
.form-grid { display: grid; grid-template-columns: 1fr; gap: 16px; }
.field { display: flex; flex-direction: column; gap: 6px; }
.field--full { grid-column: 1 / -1; }
.field label { font-weight: 600; font-size: 0.9rem; color: var(--ink); }
.field label b { color: var(--danger); }
.field input, .field textarea, .field select {
  width: 100%; padding: 12px 14px;
  border: 1.5px solid var(--ink); border-radius: 0;
  font-family: inherit; font-size: 1rem; color: var(--ink);
  background: var(--bg);
  transition: box-shadow 0.15s ease;
}
.field textarea { resize: vertical; min-height: 130px; }
.field input:focus, .field textarea:focus, .field select:focus {
  outline: none; box-shadow: 0 0 0 3px var(--accent-soft);
}
.field input[aria-invalid="true"], .field textarea[aria-invalid="true"] { border-color: var(--danger); }
.field .error-msg { display: none; font-size: 0.82rem; color: var(--danger); }
.field.has-error .error-msg { display: block; }

.form-status { display: none; margin-top: 16px; padding: 13px 16px; font-size: 0.94rem; }
.form-status--success { display: block; background: var(--accent-soft); color: var(--accent-strong); border: 1px solid var(--accent); }
.form-status--error { display: block; background: #fee2e2; color: var(--danger); border: 1px solid var(--danger); }
.form-note { margin-top: 14px; font-size: 0.85rem; color: var(--muted); }

/* ---------- 13. Interior page hero (light, Swiss) ---------- */
.page-hero {
  background: var(--bg);
  color: var(--ink);
  padding: 64px 0;
  border-bottom: 2px solid var(--ink);
}
.page-hero h1 { color: var(--ink); }
.page-hero p { color: var(--muted); max-width: 40em; font-size: 1.08rem; }

.breadcrumb { display: flex; gap: 8px; align-items: center; font-size: 0.85rem; color: var(--muted); margin-bottom: 14px; text-transform: uppercase; letter-spacing: 0.06em; }
.breadcrumb a { color: var(--accent-strong); }
.breadcrumb a:hover { color: var(--ink); }

/* ---------- 14. Notice ---------- */
.notice {
  background: var(--bg); border: 1.5px solid var(--ink);
  padding: 18px 22px; margin-top: 44px;
  font-size: 0.92rem; color: var(--muted);
}
.notice small { display: block; margin-top: 5px; color: #737373; font-size: 0.82rem; }

/* ---------- 15. Legal prose ---------- */
.prose { max-width: 780px; margin-inline: auto; }
.prose h2 { font-size: 1.35rem; margin-top: 2.2em; }
.prose p { color: var(--ink); }
.prose a { text-decoration: underline; }

/* ---------- 16. Footer ---------- */
.site-footer { background: #0a0a0a; color: #a3a3a3; padding: 64px 0 0; font-size: 0.94rem; }
.site-footer a { color: #e5e5e5; }
.site-footer a:hover { color: #7fafef; }

.site-footer__grid { display: grid; grid-template-columns: 1fr; gap: 34px; padding-bottom: 40px; }
.site-footer__brand {
  display: inline-flex; align-items: center; gap: 10px;
  font-size: 1.02rem; font-weight: 700; color: #fff;
}
.site-footer__brand:hover { color: #7fafef; }
.site-footer__brand svg { width: 32px; height: 32px; }
.site-footer__grid > div > p { margin-top: 14px; font-size: 0.88rem; max-width: 30em; }

.site-footer h4 { color: #fff; font-size: 0.8rem; letter-spacing: 0.14em; text-transform: uppercase; margin-bottom: 16px; }
.site-footer ul { list-style: none; margin: 0; padding: 0; }
.site-footer ul li { margin-bottom: 10px; }
.site-footer address { font-style: normal; line-height: 1.8; }

.site-footer__bottom {
  border-top: 1px solid #404040; padding: 20px 0;
  display: flex; flex-direction: column; gap: 10px;
  align-items: flex-start; justify-content: space-between;
  font-size: 0.84rem; color: #737373;
}
.site-footer__legal { display: flex; flex-wrap: wrap; gap: 18px; }

/* ---------- 17. Reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.is-visible { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  * { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
}

/* ---------- 17b. Skeleton utility classes (template contract) ---------- */
.cta-lede { color: #a3a3a3; max-width: 600px; margin-inline: auto; }
.h2-md { font-size: 1.5rem; }
.stack-lg { grid-template-columns: 1fr; gap: 24px; }
.head-more { margin-top: 40px; }
.cta-actions { margin-top: 24px; }
.h1--nf { font-size: clamp(2.5rem, 8vw, 4rem); color: var(--ink); }

/* ---------- 18. Chinese typography overrides ---------- */
html[lang="zh"] body { line-height: 1.8; }
html[lang="zh"] h1, html[lang="zh"] h2 { letter-spacing: 0; line-height: 1.3; }
html[lang="zh"] h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
html[lang="zh"] h2 { font-size: clamp(1.6rem, 3.4vw, 2.4rem); }
html[lang="zh"] h1 em, html[lang="zh"] h2 em { letter-spacing: 0; }
html[lang="zh"] .eyebrow { letter-spacing: 0.12em; }
html[lang="zh"] .site-nav__link { letter-spacing: 0.02em; }
html[lang="zh"] .hero__lede, html[lang="zh"] .lede, html[lang="zh"] .card p, html[lang="zh"] .process__step p { line-height: 1.85; }
html[lang="zh"] .check-list span:not(.check), html[lang="zh"] .panel__step small { line-height: 1.75; }
html[lang="zh"] .page-hero p { max-width: 36em; }

/* ---------- 19. Responsive ---------- */
@media (min-width: 640px) {
  .grid--2 { grid-template-columns: repeat(2, 1fr); }
  .grid--3 { grid-template-columns: repeat(2, 1fr); }
  .form-grid { grid-template-columns: repeat(2, 1fr); }
  .process { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 900px) {
  .grid--3 { grid-template-columns: repeat(3, 1fr); }
  .hero__grid { grid-template-columns: 1.05fr 0.95fr; }
  .contact-grid { grid-template-columns: 1fr 1.25fr; }
  .why-wrap { grid-template-columns: 1.05fr 0.95fr; gap: 40px; }
  .site-footer__grid { grid-template-columns: 1.4fr 1fr 1fr 1fr; }
  .site-footer__bottom { flex-direction: row; align-items: center; }
}

/* ---------- 20. Mobile navigation ---------- */
@media (max-width: 899px) {
  .nav-toggle { display: inline-flex; }
  .site-nav {
    position: absolute; top: var(--header-h); left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 8px;
    background: var(--bg); border-bottom: 2px solid var(--ink);
    padding: 16px 20px 22px; box-shadow: 0 18px 44px rgba(0, 0, 0, 0.18);
    display: none;
  }
  .site-nav.nav-open { display: flex; }
  .site-nav__link { padding: 12px 14px; }
  .nav-cta { margin-left: 0; width: 100%; }
}

@media (max-width: 520px) {
  .section { padding: 60px 0; }
  .hero { padding: 64px 0 72px; }
  .page-hero { padding: 48px 0; }
  .brand { font-size: 0.82rem; }
  .brand__mark { width: 32px; height: 32px; }
  .lang-toggle { padding: 6px 11px; font-size: 0.75rem; }
  .hero-card { padding: 16px; }
  .stat { padding: 12px 6px; }
  .site-footer__bottom { flex-direction: column; }
}