:root {
  --bg: #f6f7f9;
  --surface: #fff;
  --fg: #101114;
  --fg-2: #4b5058;
  --fg-3: #868d98;
  --line: #e4e6ea;
  --btn-bg: #2456d6;
  --btn-bg-hover: #1c46b4;
  --radius: 10px;
}
html[data-theme="dark"] {
  --bg: #0f1115;
  --surface: #16181d;
  --fg: #eceef2;
  --fg-2: #b0b6c0;
  --fg-3: #7c838f;
  --line: #24272e;
  --btn-bg: #3a68e0;
  --btn-bg-hover: #4a76ec;
}

* { box-sizing: border-box; }
body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 15px/1.7 -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}
main { flex: 1 0 auto; }
/* body 是纵向 flex，直接子元素要显式撑满，否则 .wrap 的 auto 外边距会触发收缩适应 */
body > header, body > main, body > footer { width: 100%; }
a { color: inherit; text-decoration: none; }
.wrap { max-width: 1040px; margin: 0 auto; padding: 0 24px; }
.main { padding-bottom: 64px; }

/* ---------- 顶部 ---------- */
header {
  position: sticky; top: 0; z-index: 10;
  background: var(--surface);
  border-bottom: 1px solid var(--line);
}
.bar { display: flex; align-items: center; gap: 20px; height: 62px; }
.brand { display: flex; align-items: center; gap: 9px; margin-right: auto; font-weight: 600; font-size: 15.5px; }
.mark { width: 26px; height: 26px; border-radius: 7px; display: block; flex: none; background: var(--btn-bg); }
.mark path { stroke: #fff; }
.t-btn {
  padding: 5px 11px; border: 1px solid var(--line); border-radius: 7px;
  background: none; color: var(--fg-2); font-size: 13px; cursor: pointer;
  transition: color .15s ease, border-color .15s ease;
}
.t-btn:hover { color: var(--fg); border-color: var(--fg-3); }

/* ---------- 文字 ---------- */
h1 { margin: 0; font-size: 30px; line-height: 1.32; font-weight: 600; letter-spacing: -.01em; }
.lead { margin: 14px 0 0; font-size: 16.5px; color: var(--fg-2); max-width: 58ch; }
.actions { margin: 26px 0 0; }
.btn {
  display: inline-flex; align-items: center; height: 40px; padding: 0 18px;
  border-radius: 8px; background: var(--btn-bg); color: #fff;
  font-size: 14.5px; font-weight: 500;
  transition: background-color .15s ease;
}
.btn:hover { background: var(--btn-bg-hover); }

/* ---------- 首屏 ---------- */
.hero { padding: 68px 0 60px; }
.hero h1 { font-size: 34px; }

/* ---------- 关于 ---------- */
.band {
  background: var(--surface);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding: 44px 0;
}
.band h2 { margin: 0 0 6px; font-size: 15px; font-weight: 600; }
.facts { margin: 0; }
.facts > div {
  display: grid; grid-template-columns: 110px 1fr; gap: 20px;
  padding: 15px 0; border-top: 1px solid var(--line);
}
.facts > div:first-child { border-top: 0; }
.facts dt { font-weight: 500; }
.facts dd { margin: 0; color: var(--fg-2); }

/* ---------- 旗下产品 ---------- */
.page-head { padding: 46px 0 4px; }
.product { margin-top: 30px; }
.p-head { display: flex; gap: 14px; }
.p-head .mark { width: 40px; height: 40px; border-radius: 10px; }
.p-head h2 { margin: 0; font-size: 19px; font-weight: 600; }
.p-head p { margin: 4px 0 0; color: var(--fg-2); max-width: 62ch; }

.lines-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: 14px; margin-top: 22px;
}
.line {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 18px;
}
.line h3 {
  display: flex; align-items: baseline; justify-content: space-between; gap: 12px;
  margin: 0 0 7px; font-size: 15px; font-weight: 600;
}
.line .count { color: var(--fg-3); font-size: 13px; font-weight: 400; }
.line p { margin: 0; color: var(--fg-2); font-size: 13.5px; line-height: 1.7; }
.more { margin: 22px 0 0; color: var(--fg-3); font-size: 13.5px; }

/* ---------- 页脚 ---------- */
footer { margin-top: 56px; background: var(--surface); border-top: 1px solid var(--line); }
.foot { padding: 26px 0; font-size: 13.5px; color: var(--fg-3); }

@media (max-width: 640px) {
  .wrap { padding: 0 18px; }
  .bar { height: 56px; }
  .t-btn { padding: 4px 8px; }
  .hero { padding: 48px 0 42px; }
  .hero h1 { font-size: 26px; }
  h1 { font-size: 25px; }
  .lead { font-size: 15.5px; }
  .facts > div { grid-template-columns: 1fr; gap: 2px; }
  .lines-grid { grid-template-columns: 1fr; }
}