:root {
  --bg: #f3f5f7;
  --surface: #ffffff;
  --ink: #1c2430;
  --muted: #5a6573;
  --line: #d5dce3;
  --accent: #0d5c52;
  --accent-soft: #e6f2ef;
  --navy: #1a2744;
  --warn: #6b5344;
  --radius: 8px;
  --shadow: 0 10px 30px rgb(26 39 68 / 0.06);
  --max: 1080px;
  --nav-h: 64px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--bg);
  font-family: "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.6;
}

img {
  max-width: 100%;
  height: auto;
}

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

a:hover {
  color: var(--navy);
}

.skip {
  position: absolute;
  left: 12px;
  top: -40px;
  background: var(--navy);
  color: #fff;
  padding: 8px 12px;
  z-index: 20;
}

.skip:focus {
  top: 12px;
}

.wrap {
  width: min(var(--max), calc(100% - 40px));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  height: var(--nav-h);
  background: rgb(243 245 247 / 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  height: var(--nav-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--navy);
  text-decoration: none;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.brand:hover {
  color: var(--navy);
}

.mark {
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  background: var(--navy);
  color: #eef3f1;
  font-size: 12px;
  font-weight: 700;
  border-radius: 4px;
}

.nav {
  display: flex;
  align-items: center;
  gap: 18px;
}

.nav a {
  color: var(--ink);
  text-decoration: none;
  font-size: 14px;
}

.nav a:hover {
  color: var(--accent);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.lang {
  display: flex;
  border: 1px solid var(--line);
  border-radius: 999px;
  overflow: hidden;
  background: var(--surface);
}

.lang button {
  border: 0;
  background: transparent;
  color: var(--muted);
  padding: 6px 10px;
  font: inherit;
  font-size: 12px;
  cursor: pointer;
}

.lang button[aria-pressed="true"] {
  background: var(--navy);
  color: #fff;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 0 16px;
  border-radius: var(--radius);
  border: 1px solid transparent;
  font: inherit;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  white-space: nowrap;
}

.btn:active {
  transform: translateY(1px);
}

.btn-primary {
  background: var(--accent);
  color: #f4fbf9;
}

.btn-primary:hover {
  background: #0a4b43;
  color: #fff;
}

.btn-ghost {
  background: transparent;
  border-color: var(--line);
  color: var(--ink);
}

.btn-ghost:hover {
  border-color: var(--navy);
  color: var(--navy);
}

.menu-btn {
  display: none;
  width: 40px;
  height: 40px;
  border: 1px solid var(--line);
  background: var(--surface);
  border-radius: 8px;
  cursor: pointer;
}

.menu-btn span {
  display: block;
  width: 16px;
  height: 1.5px;
  margin: 3px auto;
  background: var(--ink);
}

.hero {
  min-height: calc(100dvh - var(--nav-h));
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 40px;
  align-items: center;
  padding: 48px 0 64px;
}

.kicker {
  margin: 0 0 12px;
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
}

.hero h1 {
  margin: 0 0 16px;
  color: var(--navy);
  font-size: clamp(36px, 5vw, 56px);
  line-height: 1.15;
  letter-spacing: -0.03em;
}

.lede,
.support {
  max-width: 52ch;
  color: var(--muted);
}

.lede {
  margin: 0 0 12px;
  color: var(--ink);
  font-size: 18px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.panel {
  position: relative;
  background: var(--navy);
  color: #dbe4ee;
  border-radius: 12px;
  padding: 22px;
  min-height: 320px;
  overflow: hidden;
  box-shadow: var(--shadow);
}

.panel h2 {
  margin: 0 0 14px;
  color: #fff;
  font-size: 16px;
}

.watermark {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  pointer-events: none;
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: rgb(255 255 255 / 0.08);
  transform: rotate(-18deg);
}

.schema-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}

.schema-table th,
.schema-table td {
  text-align: left;
  padding: 8px 0;
  border-bottom: 1px solid rgb(255 255 255 / 0.12);
  vertical-align: top;
}

.schema-table th {
  width: 34%;
  color: #9eb0c4;
  font-weight: 500;
}

.tag {
  display: inline-block;
  margin-top: 14px;
  padding: 4px 8px;
  border: 1px solid rgb(255 255 255 / 0.2);
  border-radius: 999px;
  font-size: 12px;
  color: #c5d6c9;
}

section {
  padding: 72px 0;
}

.section-title {
  margin: 0 0 10px;
  color: var(--navy);
  font-size: clamp(28px, 4vw, 36px);
  letter-spacing: -0.03em;
  line-height: 1.2;
}

.section-desc {
  margin: 0 0 28px;
  max-width: 62ch;
  color: var(--muted);
}

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 24px;
}

.card h3 {
  margin: 0 0 12px;
  font-size: 22px;
}

.card ul,
.prose ul {
  margin: 0;
  padding-left: 18px;
}

.card li + li,
.prose li + li {
  margin-top: 8px;
}

.card.accent {
  background: var(--navy);
  color: #d7e0ea;
  border-color: var(--navy);
}

.card.accent h3,
.card.accent .zh,
.card.accent .en {
  color: #fff;
}

.note {
  margin-top: 16px;
  padding: 10px 12px;
  background: var(--accent-soft);
  color: var(--navy);
  border-radius: 8px;
  font-size: 13px;
}

.flow {
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr;
  gap: 10px;
  align-items: stretch;
}

.flow-box,
.scope-item {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 18px;
}

.flow-box strong {
  display: block;
  margin-bottom: 6px;
  color: var(--navy);
}

.arrow {
  display: grid;
  place-items: center;
  color: var(--muted);
  font-size: 22px;
}

.scope {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.scope h3 {
  margin: 0 0 10px;
}

.out {
  border-color: #e2d4c8;
  background: #fbf7f3;
}

.dl {
  display: grid;
  gap: 12px;
}

.dl div {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px 18px;
}

.dl dt {
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 6px;
}

.dl dd {
  margin: 0;
  color: var(--muted);
}

.contact-grid {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 22px;
}

label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 6px;
}

input,
select,
textarea {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 10px 12px;
  font: inherit;
  color: var(--ink);
  background: #fff;
}

input:focus,
select:focus,
textarea:focus {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}

.field {
  margin-bottom: 14px;
}

.help {
  margin: 6px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.placeholder {
  font-family: ui-monospace, "Cascadia Mono", Consolas, monospace;
  background: #fff6d8;
  padding: 0 4px;
  border-radius: 4px;
}

.site-footer {
  border-top: 1px solid var(--line);
  padding: 28px 0 40px;
  color: var(--muted);
  font-size: 14px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr 1fr;
  gap: 18px;
}

.site-footer h2 {
  margin: 0 0 8px;
  color: var(--navy);
  font-size: 14px;
}

.site-footer ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-footer li + li {
  margin-top: 6px;
}

.legal-page {
  padding: 48px 0 80px;
}

.prose {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 28px;
}

.prose h1 {
  margin-top: 0;
  color: var(--navy);
}

.prose h2 {
  margin-top: 28px;
  color: var(--navy);
  font-size: 20px;
}

.banner {
  margin: 0 0 20px;
  padding: 12px 14px;
  background: var(--accent-soft);
  border-radius: 8px;
}

html[data-lang="zh"] .en {
  display: none !important;
}

html[data-lang="en"] .zh {
  display: none !important;
}

html[data-lang="en"] .en.inline,
html[data-lang="zh"] .zh.inline {
  display: inline !important;
}

@media (max-width: 1120px) {
  .hero,
  .split,
  .scope,
  .contact-grid,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .flow {
    grid-template-columns: 1fr;
  }

  .arrow {
    transform: rotate(90deg);
  }

  .nav {
    display: none;
    position: absolute;
    top: var(--nav-h);
    left: 0;
    right: 0;
    background: #fff;
    border-bottom: 1px solid var(--line);
    padding: 12px 20px 18px;
    flex-direction: column;
    align-items: flex-start;
  }

  .nav a {
    padding: 8px 0;
  }

  .nav.open {
    display: flex;
  }

  .menu-btn {
    display: inline-block;
  }

  .nav-actions .btn {
    display: none;
  }

  .hero {
    min-height: 0;
    padding: 32px 0 48px;
  }

  section {
    padding: 56px 0;
  }
}

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

  .btn:active {
    transform: none;
  }
}