:root {
  --bg: #f7f9fc;
  --surface: #ffffff;
  --surface-2: #eef2f8;
  --text: #11233d;
  --text-soft: #5b6b85;
  --primary: #1e63d8;
  --primary-dark: #1340a8;
  --accent: #ff7a18;
  --teal: #13b5a6;
  --line: #e2e8f2;
  --shadow: 0 10px 30px rgba(20,40,80,0.08);
  --radius: 16px;
  --maxw: 1160px;
  font-family: -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }

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

/* ---------- Header ---------- */
header.site {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,0.9);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 20px; color: var(--primary); }
.logo .mark { width: 34px; height: 34px; border-radius: 9px; background: linear-gradient(135deg, var(--primary), var(--teal)); display: grid; place-items: center; color: #fff; font-size: 18px; }
.nav-links { display: flex; gap: 26px; align-items: center; }
.nav-links a { color: var(--text-soft); font-weight: 600; font-size: 15px; transition: color .2s; }
.nav-links a:hover, .nav-links a.active { color: var(--primary); }
/* 导航内 CTA 按钮：保持白字，覆盖上方链接配色规则 */
.nav-links a.btn { color: #fff; }
.nav-links a.btn:hover, .nav-links a.btn.active { color: #fff; }
.btn {
  display: inline-block; padding: 10px 20px; border-radius: 999px;
  background: var(--primary); color: #fff; font-weight: 700; cursor: pointer; border: none;
  transition: transform .15s, box-shadow .2s; font-size: 15px;
}
.btn:hover { transform: translateY(-2px); box-shadow: 0 8px 20px rgba(30,99,216,.28); }
.btn.ghost { background: var(--surface); color: var(--primary); border: 2px solid var(--primary); box-shadow: 0 4px 12px rgba(30,99,216,.14); }
.btn.accent { background: var(--accent); color: #fff; box-shadow: 0 6px 16px rgba(255,122,24,.32); }

.lang-switch { display: flex; align-items: center; gap: 2px; margin-left: 10px; background: var(--surface); border: 1px solid #e3e9f2; border-radius: 999px; padding: 3px 4px; }
.lang-switch a { font-size: 13px; font-weight: 700; color: var(--text-soft); text-decoration: none; padding: 4px 10px; border-radius: 999px; line-height: 1; transition: .2s; }
.lang-switch a:hover { color: var(--primary); }
.lang-switch a.active { background: var(--primary); color: #fff; }
.lang-switch a.active:hover { color: #fff; }

/* ---------- Hero ---------- */
.hero { position: relative; overflow: hidden; padding: 80px 0 70px;
  background: linear-gradient(135deg, #eaf2ff 0%, #f7f9fc 55%, #eafaf7 100%); }
.hero h1 { font-size: 44px; line-height: 1.2; font-weight: 800; letter-spacing: -1px; }
.hero h1 .c { color: var(--primary); }
.hero p { margin: 18px 0 28px; font-size: 18px; color: var(--text-soft); max-width: 640px; }
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 40px; align-items: center; }
.hero-stats { display: grid; grid-template-columns: repeat(3,1fr); gap: 16px; margin-top: 38px; }
.stat { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; padding: 18px; box-shadow: var(--shadow); }
.stat .num { font-size: 28px; font-weight: 800; color: var(--primary); }
.stat .label { font-size: 13px; color: var(--text-soft); margin-top: 4px; }
.hero-card { background: linear-gradient(160deg, var(--primary), #2f7be0); color: #fff; border-radius: 20px; padding: 28px; box-shadow: var(--shadow); }
.hero-card h3 { font-size: 18px; margin-bottom: 14px; }
.hero-card ul { list-style: none; display: grid; gap: 12px; }
.hero-card li { display: flex; gap: 10px; align-items: flex-start; font-size: 14px; }
.hero-card .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--accent); margin-top: 7px; flex: none; }

/* ---------- Sections ---------- */
section { padding: 64px 0; }
.section-head { text-align: center; margin-bottom: 40px; }
.section-head .eyebrow { color: var(--accent); font-weight: 700; letter-spacing: 2px; font-size: 14px; }
.section-head h2 { font-size: 32px; font-weight: 800; margin: 8px 0 10px; }
.section-head p { color: var(--text-soft); max-width: 640px; margin: 0 auto; }

.cards { display: grid; grid-template-columns: repeat(3,1fr); gap: 22px; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 26px; box-shadow: var(--shadow); transition: transform .2s; }
.card:hover { transform: translateY(-4px); }
.card .ic { width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center; font-size: 22px; margin-bottom: 14px; }
.card h3 { font-size: 19px; margin-bottom: 8px; }
.card p { color: var(--text-soft); font-size: 15px; }

.flow { display: grid; grid-template-columns: repeat(4,1fr); gap: 18px; counter-reset: step; }
.step { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; position: relative; }
.step::before { counter-increment: step; content: counter(step); position: absolute; top: -16px; left: 24px; width: 34px; height: 34px; border-radius: 50%; background: var(--primary); color: #fff; display: grid; place-items: center; font-weight: 800; }
.step h4 { margin-top: 12px; font-size: 17px; }
.step p { color: var(--text-soft); font-size: 14px; margin-top: 6px; }

.pricing { background: var(--surface-2); }
.price-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 22px; }
.price-card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 28px; box-shadow: var(--shadow); }
.price-card.feature { border: 2px solid var(--primary); position: relative; }
.price-card .tag { position: absolute; top: -12px; right: 20px; background: var(--accent); color: #fff; font-size: 12px; padding: 4px 12px; border-radius: 999px; }
.price-card h3 { font-size: 20px; }
.price-card .price { font-size: 34px; font-weight: 800; color: var(--primary); margin: 10px  ﹔ }
.price-card ul { list-style: none; margin-top: 16px; display: grid; gap: 10px; }
.price-card li { color: var(--text-soft); font-size: 14px; padding-left: 22px; position: relative; }
.price-card li::before { content: "✓"; position: absolute; left: 0; color: var(--teal); font-weight: 800; }

/* ---------- Cost calculator ---------- */
.calc { display: grid; grid-template-columns: 1fr 1fr; gap: 30px; }
.calc-form { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 28px; box-shadow: var(--shadow); }
.field { margin-bottom: 18px; }
.field label { display: block; font-weight: 700; margin-bottom: 7px; font-size: 14px; }
.field input, .field select { width: 100%; padding: 11px 13px; border: 1px solid var(--line); border-radius: 10px; font-size: 15px; background: #fff; color: var(--text); }
.field .hint { font-size: 12px; color: var(--text-soft); margin-top: 5px; }
.calc-result { background: linear-gradient(160deg, #0f2a5e, #1e63d8); color: #fff; border-radius: var(--radius); padding: 28px; }
.calc-result h3 { font-size: 18px; margin-bottom: 16px; }
.big-num { font-size: 40px; font-weight: 800; color: #fff; }
.big-num small { font-size: 16px; opacity: .8; }
.breakdown { margin-top: 18px; display: grid; gap: 10px; }
.breakdown .row { display: flex; justify-content: space-between; font-size: 14px; padding: 10px 0; border-bottom: 1px solid rgba(255,255,255,.15); }
.breakdown .row.total { border-bottom: none; font-weight: 800; font-size: 16px; }
.calc-note { font-size: 12px; opacity: .8; margin-top: 16px; }

/* ---------- Blog ---------- */
.blog-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 22px; }
.post { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); transition: transform .2s; }
.post:hover { transform: translateY(-4px); }
.post .thumb { height: 150px; background: linear-gradient(135deg, var(--primary), var(--teal)); display: grid; place-items: center; color: #fff; font-size: 28px; }
.post .body { padding: 20px; }
.post .meta { font-size: 12px; color: var(--text-soft); margin-bottom: 8px; }
.post h3 { font-size: 18px; margin-bottom: 8px; }
.post p { color: var(--text-soft); font-size: 14px; }
.post .read { display: inline-block; margin-top: 12px; color: var(--primary); font-weight: 700; font-size: 14px; }

/* ---------- Footer ---------- */
footer { background: #0f2a5e; color: #cfe0ff; padding: 48px 0 30px; }
footer .cols { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 30px; }
footer h4 { color: #fff; margin-bottom: 14px; font-size: 16px; }
footer a { color: #cfe0ff; display: block; margin-bottom: 8px; font-size: 14px; }
footer a:hover { color: #fff; }
footer .copy { margin-top: 30px; padding-top: 20px; border-top: 1px solid rgba(255,255,255,.15); font-size: 13px; color: #9fb6de; }
footer .beian { margin-top: 10px; font-size: 13px; color: #9fb6de; }
footer .beian a { display: inline; margin: 0; color: #cfe0ff; }
footer .beian a:hover { color: #fff; }

/* ---------- Article ---------- */
.article { max-width: 760px; margin: 0 auto; background: var(--surface); border-radius: var(--radius); padding: 40px; box-shadow: var(--shadow); }
.article h1 { font-size: 30px; margin-bottom: 12px; }
.article .meta { color: var(--text-soft); margin-bottom: 24px; font-size: 14px; }
.article p { margin-bottom: 16px; }
.article h2 { font-size: 22px; margin: 28px 0 12px; }
.article pre { background: #0f2a5e; color: #eaf2ff; padding: 16px; border-radius: 10px; overflow-x: auto; font-size: 13px; }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .hero-grid, .calc, .cards, .price-grid, .blog-grid, .flow, footer .cols { grid-template-columns: 1fr; }
  .nav-links { display: none; }
  .hero h1 { font-size: 32px; }
}