:root {
  --bg: #f3f7fd;
  --surface: #fff;
  --surface-soft: #f8fbff;
  --line: #d7e3f3;
  --ink: #1a2333;
  --muted: #5f6f87;
  --brand: #0b4f6c;
  --brand-2: #02a8c4;
  --max: 1140px;
  --shadow: 0 10px 28px rgba(13, 37, 72, 0.1);
}

* { box-sizing: border-box; }
body { margin: 0; color: var(--ink); font-family: "PingFang SC", "Microsoft YaHei", sans-serif; line-height: 1.65; background: var(--bg); }
a { color: inherit; text-decoration: none; }
.container { width: min(100% - 2rem, var(--max)); margin: 0 auto; }

.site-header { position: sticky; top: 0; z-index: 20; border-bottom: 1px solid var(--line); background: var(--surface); }
.nav-wrap { min-height: 72px; display: flex; align-items: center; gap: 1rem; }
.brand { color: var(--brand); font-weight: 800; white-space: nowrap; }
.main-nav { margin-left: auto; display: flex; gap: 0.8rem; }
.main-nav a { color: var(--muted); font-weight: 700; padding: 0.35rem 0.55rem; border-radius: 999px; }
.main-nav a:hover { color: var(--brand); background: #def4f9; }
.quick-actions { display: flex; gap: 0.5rem; }
.menu-toggle { display: none; margin-left: auto; border: 1px solid var(--line); background: #fff; border-radius: 8px; padding: 0.35rem 0.7rem; }

.section { padding: 3rem 0; }
.alt { background: var(--surface-soft); }
.hero-grid, .grid-4, .grid-3, .grid-2, .two-col, .contact-grid { display: grid; gap: 1rem; }
.hero-grid { grid-template-columns: 1.2fr .8fr; }
.grid-4 { grid-template-columns: repeat(4,1fr); }
.grid-3 { grid-template-columns: repeat(3,1fr); }
.grid-2 { grid-template-columns: repeat(2,1fr); }
.two-col, .contact-grid { grid-template-columns: 1fr 1fr; }

h1 { margin: .4rem 0 .9rem; font-size: clamp(1.8rem, 4vw, 2.8rem); line-height: 1.2; }
h2 { margin: 0 0 1rem; font-size: clamp(1.4rem, 3vw, 2rem); }
.eyebrow { margin: 0; color: var(--brand); font-weight: 800; }
.lead, .muted { color: var(--muted); }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: 16px; box-shadow: var(--shadow); padding: 1rem; }
.tag-list { margin: 1rem 0 0; padding: 0; list-style: none; display: flex; gap: .5rem; flex-wrap: wrap; }
.tag-list li { border: 1px solid var(--line); border-radius: 999px; padding: .3rem .75rem; background: #fff; font-size: .86rem; }

.btn { display: inline-flex; align-items: center; justify-content: center; border-radius: 999px; border: 1px solid transparent; padding: .56rem 1rem; font-weight: 700; cursor: pointer; }
.btn-primary { color: #fff; background: linear-gradient(120deg, var(--brand), var(--brand-2)); }
.btn-light { border-color: var(--line); background: #fff; }
.btn-outline { border-color: var(--brand); color: var(--brand); background: #fff; }
.hero-cta { display: flex; gap: .6rem; flex-wrap: wrap; }

.contact-form { display: grid; gap: .7rem; }
label { display: grid; gap: .25rem; font-weight: 600; }
input, textarea { width: 100%; border: 1px solid var(--line); border-radius: 10px; padding: .65rem .8rem; font: inherit; }

.site-footer { border-top: 1px solid var(--line); background: #fff; color: var(--muted); }
.footer-wrap { min-height: 64px; display: flex; justify-content: space-between; align-items: center; gap: 1rem; flex-wrap: wrap; }
.to-top { position: fixed; right: 1rem; bottom: 1rem; width: 44px; height: 44px; border: none; border-radius: 50%; background: linear-gradient(140deg, var(--brand), var(--brand-2)); color: #fff; display: none; }

@media (max-width: 980px) {
  .grid-4 { grid-template-columns: repeat(2,1fr); }
  .grid-3 { grid-template-columns: 1fr; }
  .hero-grid, .grid-2, .two-col, .contact-grid { grid-template-columns: 1fr; }
}

@media (max-width: 860px) {
  .quick-actions, .main-nav { display: none; }
  .menu-toggle { display: inline-flex; }
  .main-nav.open { position: absolute; left: 0; top: 72px; width: 100%; display: grid; background: #fff; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); padding: .5rem 1rem 1rem; }
  .main-nav.open a { padding: .65rem 0; }
}