:root {
  --bg: #ffffff;
  --bg-soft: #f5f7fb;
  --bg-dark: #0f1b2d;
  --text: #1f2937;
  --text-soft: #5b6475;
  --text-inv: #e8edf5;
  --line: #e4e8ef;
  --brand: #0a5cff;
  --brand-dark: #0645c4;
  --brand-soft: #e7f0ff;
  --accent: #0ea47a;
  --radius: 12px;
  --shadow: 0 6px 24px rgba(15, 27, 45, .06);
  --max: 1160px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--brand); text-decoration: none; }
a:hover { color: var(--brand-dark); }
img { max-width: 100%; }

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

/* ── header ─────────────────────────── */
.hd {
  position: sticky; top: 0; z-index: 10;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.hd .wrap { display: flex; align-items: center; gap: 28px; height: 64px; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 19px; color: var(--text); }
.logo-img { height: 32px; width: auto; display: block; }
.logo-txt { font-weight: 800; letter-spacing: .06em; color: #0b1220; }
.ft .logo-txt { color: #fff; }
.nav { display: flex; gap: 22px; margin-left: auto; }
.nav a { color: var(--text-soft); font-size: 15px; }
.nav a:hover, .nav a.on { color: var(--brand); }
.lang { position: relative; }
.lang-btn {
  display: flex; align-items: center; gap: 6px;
  border: 1px solid var(--line); background: var(--bg); color: var(--text);
  border-radius: 999px; padding: 5px 10px 5px 12px; font-size: 13px; cursor: pointer; font-family: inherit;
  width: 132px;                /* 固定宽度：切换语种时按钮不变宽变窄，页头不跟着跳 */
}
.lang-btn svg { width: 15px; height: 15px; flex: 0 0 auto; }
.lang-btn #langCur { flex: 1 1 auto; min-width: 0; text-align: left; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.lang-btn .caret { width: 13px; height: 13px; transition: transform .15s; }
.lang-btn:hover, .lang.open .lang-btn { border-color: var(--brand); color: var(--brand); }
.lang.open .caret { transform: rotate(180deg); }
.lang-menu {
  display: none; position: absolute; right: 0; top: calc(100% + 6px); z-index: 20;
  width: 100%; min-width: 132px; margin: 0; padding: 6px; list-style: none;
  background: var(--bg); border: 1px solid var(--line); border-radius: 10px; box-shadow: var(--shadow);
}
.lang.open .lang-menu { display: block; }
.lang-menu li {
  padding: 7px 12px; border-radius: 6px; font-size: 14px; cursor: pointer;
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
}
.lang-menu li:hover { background: var(--bg-soft); color: var(--brand); }
.lang-menu li.on { color: var(--brand); font-weight: 600; }
.lang-menu li.on::after { content: "✓"; font-size: 12px; }

/* ── buttons ─────────────────────────── */
.btn {
  display: inline-block; padding: 12px 26px; border-radius: 8px;
  font-weight: 600; font-size: 15px; border: 1px solid transparent;
}
.btn-primary { background: var(--brand); color: #fff; }
.btn-primary:hover { background: var(--brand-dark); color: #fff; }
.btn-ghost { border-color: var(--line); color: var(--text); background: var(--bg); }
.btn-ghost:hover { border-color: var(--brand); color: var(--brand); }

/* ── hero ─────────────────────────── */
.hero { padding: 88px 0 72px; background: linear-gradient(180deg, var(--brand-soft), var(--bg)); }
.hero .wrap { display: grid; grid-template-columns: 1.1fr .9fr; gap: 48px; align-items: center; }
.eyebrow { color: var(--brand); font-weight: 600; font-size: 14px; letter-spacing: .04em; text-transform: uppercase; }
.hero h1 { font-size: 44px; line-height: 1.2; margin: 12px 0 18px; }
.hero p.lead { font-size: 18px; color: var(--text-soft); margin: 0 0 30px; }
.hero .cta { display: flex; gap: 12px; flex-wrap: wrap; }
.hero-card {
  background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow); padding: 24px;
}
.flow { list-style: none; margin: 0; padding: 0; }
.flow li { display: flex; gap: 14px; padding: 12px 0; border-bottom: 1px dashed var(--line); }
.flow li:last-child { border-bottom: 0; }
.flow b { display: block; font-size: 15px; }
.flow span.d { color: var(--text-soft); font-size: 14px; }
.flow .n {
  flex: 0 0 30px; height: 30px; border-radius: 50%;
  background: var(--brand-soft); color: var(--brand); font-weight: 700;
  display: grid; place-items: center; font-size: 14px;
}

/* ── sections ─────────────────────────── */
section { padding: 72px 0; }
section.soft { background: var(--bg-soft); }
.sec-hd { text-align: center; max-width: 720px; margin: 0 auto 44px; }
.sec-hd h2 { font-size: 32px; margin: 8px 0 12px; line-height: 1.3; }
.sec-hd p { color: var(--text-soft); margin: 0; }

.grid3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.card {
  background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px; box-shadow: var(--shadow);
}
.card h3 { margin: 12px 0 8px; font-size: 19px; }
.card p { margin: 0; color: var(--text-soft); font-size: 15px; }
.ico {
  width: 44px; height: 44px; border-radius: 10px; background: var(--brand-soft);
  display: grid; place-items: center; color: var(--brand);
}
.ico svg { width: 24px; height: 24px; }

/* ── module blocks ─────────────────────────── */
.module { display: grid; grid-template-columns: 300px 1fr; gap: 40px; padding: 40px 0; border-top: 1px solid var(--line); }
.module:first-of-type { border-top: 0; }
.module-tag {
  display: inline-block; padding: 3px 12px; border-radius: 999px;
  background: var(--brand); color: #fff; font-weight: 700; font-size: 13px; letter-spacing: .05em;
}
.module h3 { font-size: 24px; margin: 14px 0 10px; }
.module .intro { color: var(--text-soft); margin: 0; }
.feats { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; }
.feat { background: var(--bg); border: 1px solid var(--line); border-radius: 10px; padding: 16px 18px; }
.feat b { display: block; margin-bottom: 4px; font-size: 15px; }
.feat span { color: var(--text-soft); font-size: 14px; }

/* ── stats / warehouse ─────────────────────────── */
.dark { background: var(--bg-dark); color: var(--text-inv); }
.dark .sec-hd p, .dark .card p { color: #a9b4c6; }
.dark .card { background: #16253c; border-color: #22344f; box-shadow: none; }
.dark .ico { background: #1d3150; color: #7fb0ff; }

/* ── steps ─────────────────────────── */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; counter-reset: s; }
.step { position: relative; padding-top: 52px; }
.step::before {
  counter-increment: s; content: counter(s);
  position: absolute; top: 0; left: 0; width: 38px; height: 38px; border-radius: 50%;
  background: var(--brand); color: #fff; font-weight: 700; display: grid; place-items: center;
}
.step b { display: block; margin-bottom: 6px; }
.step span { color: var(--text-soft); font-size: 15px; }

/* ── contact ─────────────────────────── */
.contact { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.contact .card b { display: block; color: var(--text-soft); font-weight: 500; font-size: 14px; }
.contact .card div { font-size: 17px; font-weight: 600; margin-top: 4px; word-break: break-all; }

/* ── faq ─────────────────────────── */
.faq-hero { padding: 64px 0 32px; background: linear-gradient(180deg, var(--brand-soft), var(--bg)); text-align: center; }
.faq-hero h1 { font-size: 38px; margin: 8px 0 12px; }
.faq-hero p { color: var(--text-soft); margin: 0; }
.faq-layout { display: grid; grid-template-columns: 220px 1fr; gap: 40px; padding: 32px 0 80px; }
.faq-toc { position: sticky; top: 88px; align-self: start; display: flex; flex-direction: column; gap: 4px; }
.faq-toc a { color: var(--text-soft); padding: 7px 12px; border-radius: 8px; font-size: 15px; }
.faq-toc a:hover { background: var(--bg-soft); color: var(--brand); }
.faq-group { margin-bottom: 40px; scroll-margin-top: 88px; }
.faq-group h2 { font-size: 22px; margin: 0 0 14px; }
details {
  border: 1px solid var(--line); border-radius: 10px; margin-bottom: 10px; background: var(--bg);
}
details[open] { box-shadow: var(--shadow); }
summary {
  cursor: pointer; list-style: none; padding: 16px 48px 16px 20px; font-weight: 600; position: relative;
}
summary::-webkit-details-marker { display: none; }
summary::after {
  content: "+"; position: absolute; right: 20px; top: 50%; transform: translateY(-50%);
  color: var(--brand); font-size: 22px; font-weight: 400;
}
details[open] summary::after { content: "−"; }
details .a { padding: 0 20px 18px; color: var(--text-soft); }
details .a p { margin: 0 0 8px; }
details .a ol, details .a ul { margin: 0; padding-left: 20px; }

/* ── policy doc ─────────────────────────── */
.doc { max-width: 780px; }
.doc .meta { color: var(--text-soft); font-size: 14px; margin: 0 0 28px; }
.doc section { padding: 0; margin-bottom: 36px; scroll-margin-top: 88px; }
.doc h2 { font-size: 21px; margin: 0 0 12px; }
.doc h3 { font-size: 17px; margin: 18px 0 8px; }
.doc p, .doc li { color: var(--text-soft); }
.doc p { margin: 0 0 12px; }
.doc ul { margin: 0 0 12px; padding-left: 22px; }
.doc li { margin-bottom: 6px; }
.doc li b, .doc p b { color: var(--text); }

/* ── footer ─────────────────────────── */
.ft { background: var(--bg-dark); color: #a9b4c6; padding: 40px 0; font-size: 14px; }
.ft .wrap { display: flex; flex-wrap: wrap; gap: 16px 32px; align-items: center; justify-content: space-between; }
.ft a { color: #cfd8e6; }
.ft-links { display: flex; gap: 22px; flex-wrap: wrap; }

/* ── responsive ─────────────────────────── */
@media (max-width: 960px) {
  .hero .wrap, .module { grid-template-columns: 1fr; gap: 28px; }
  .grid3, .contact { grid-template-columns: 1fr 1fr; }
  .steps { grid-template-columns: 1fr 1fr; }
  .faq-layout { grid-template-columns: 1fr; }
  .faq-toc { position: static; flex-direction: row; flex-wrap: wrap; }
}
@media (max-width: 640px) {
  .wrap { padding: 0 16px; }
  .nav { display: none; }
  .hd .wrap { gap: 12px; }
  .lang { margin-left: auto; }
  .hero { padding: 56px 0 48px; }
  .hero h1 { font-size: 32px; }
  .sec-hd h2 { font-size: 26px; }
  section { padding: 52px 0; }
  .grid3, .contact, .feats, .steps { grid-template-columns: 1fr; }
}
.ft .icp { margin-left: 14px; color: #a9b4c6; white-space: nowrap; }
.ft .icp:hover { color: #fff; }