/* 比特浏览器 常见问题 —— 配色沿用主站：#fff 底 / #3370ff 品牌蓝 / #04102c 页脚深蓝 */
:root {
  --bg: #fff;
  --bg2: #f5f7fb;
  --bg3: #eef2f9;
  --line: #e5e9f2;
  --line2: #d4dbe8;
  --fg: #2a3142;
  --fg2: #565f74;
  --fg3: #8a93a6;
  --bl: #3370ff;
  --bl2: #1f5cf0;
  --bl-dim: rgba(51, 112, 255, .07);
  --grad: linear-gradient(90.26deg, #6593ff -1.1%, #3370ff 99.77%);
  --navy: #04102c;
  --maxw: 900px;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--fg2);
  font-family: Inter, PingFangSC-Regular, "PingFang SC", SourceHanSansCN, "Microsoft YaHei", Roboto, -apple-system, "Helvetica Neue", Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  line-height: 1.78;
  font-size: 16px;
}
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
img, svg { max-width: 100%; display: block; }
code, kbd, pre { font-family: "Cascadia Code", Consolas, "SF Mono", Menlo, monospace; }

/* ===== 顶栏 ===== */
.hd {
  position: sticky; top: 0; z-index: 20;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: saturate(160%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.hd-in {
  max-width: var(--maxw); margin: 0 auto; padding: 0 20px;
  height: 62px; display: flex; align-items: center; gap: 14px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; letter-spacing: .3px; color: var(--fg); }
.brand svg { width: 27px; height: 27px; flex: none; }
.brand .brand-logo { height: 26px; width: auto; display: block; }
.brand b { font-size: 18px; }
.brand b em { color: var(--bl); font-style: normal; }
.brand span {
  font-size: 12px; color: var(--fg3); font-weight: 400; letter-spacing: 0;
  padding-left: 10px; margin-left: 2px; border-left: 1px solid var(--line2);
}
.hd .sp { flex: 1; }
.hd-back {
  font-size: 13px; color: var(--fg2); padding: 6px 14px; white-space: nowrap;
  border: 1px solid var(--line2); border-radius: 999px;
  transition: border-color .18s, color .18s;
}
.hd-back:hover { color: var(--bl); border-color: var(--bl); }

/* ===== 页面容器 ===== */
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }
.hero { padding: 54px 0 28px; }
.hero h1 { font-size: 32px; line-height: 1.35; letter-spacing: -.2px; color: var(--fg); }
.hero h1 em { color: var(--bl); font-style: normal; }
.hero p { margin-top: 13px; color: var(--fg2); font-size: 15px; max-width: 70ch; }
.hero .meta { margin-top: 18px; font-size: 12.5px; color: var(--fg3); display: flex; gap: 8px 18px; flex-wrap: wrap; }
.hero .meta b { color: var(--fg2); font-weight: 500; }

/* ===== 搜索 + 分类筛选 ===== */
.tools { padding-bottom: 22px; border-bottom: 1px solid var(--line); }
.search {
  width: 100%; background: var(--bg2); border: 1px solid var(--line2);
  color: var(--fg); font-size: 14.5px; padding: 12px 16px; border-radius: 10px;
  font-family: inherit; outline: none; transition: border-color .18s, box-shadow .18s;
}
.search:focus { border-color: var(--bl); box-shadow: 0 0 0 3px var(--bl-dim); }
.search::placeholder { color: var(--fg3); }
.cats { margin-top: 14px; display: flex; gap: 8px; flex-wrap: wrap; }
.cat {
  font-size: 13px; color: var(--fg2); background: var(--bg2);
  border: 1px solid var(--line2); border-radius: 999px;
  padding: 5px 14px; cursor: pointer; user-select: none;
  transition: all .18s; font-family: inherit;
}
.cat:hover { color: var(--fg); border-color: var(--fg3); }
.cat.on { background: var(--bl-dim); border-color: var(--bl); color: var(--bl); }
.cat i { font-style: normal; opacity: .55; margin-left: 5px; font-size: 11.5px; }

/* ===== FAQ 列表 ===== */
.list { padding: 8px 0 40px; }
.qa { border-bottom: 1px solid var(--line); }
.qa[hidden] { display: none; }
.qa-q {
  width: 100%; background: none; border: 0; color: var(--fg);
  font-family: inherit; font-size: 16.5px; font-weight: 600; line-height: 1.6;
  text-align: left; cursor: pointer; padding: 19px 40px 19px 0;
  position: relative; display: block;
}
.qa-q:hover { color: var(--bl); }
.qa-q::after {
  content: ""; position: absolute; right: 6px; top: 50%;
  width: 8px; height: 8px; margin-top: -6px;
  border-right: 1.8px solid var(--fg3); border-bottom: 1.8px solid var(--fg3);
  transform: rotate(45deg); transition: transform .22s, border-color .22s;
}
.qa.open .qa-q::after { transform: rotate(-135deg); margin-top: -2px; border-color: var(--bl); }
.qa-tag {
  display: inline-block; font-size: 11.5px; font-weight: 400;
  color: var(--fg3); border: 1px solid var(--line2);
  border-radius: 4px; padding: 1px 7px; margin-right: 9px;
  vertical-align: 2px;
}
.qa-body { display: none; padding: 0 0 22px; }
.qa.open .qa-body { display: block; }
.qa-sum { color: var(--fg2); font-size: 15px; max-width: 74ch; }
/* 列表内的发布信息行：发布时间：2026-06-30 访问量：47 */
.qa-info {
  margin-top: 12px; font-size: 12.5px; color: var(--fg3);
  display: flex; gap: 18px; flex-wrap: wrap; font-feature-settings: "tnum";
}
.qa-foot { margin-top: 15px; display: flex; align-items: center; gap: 14px; flex-wrap: wrap; }
.qa-more {
  display: inline-flex; align-items: center; gap: 7px;
  font-size: 13.5px; color: #fff; background: var(--grad);
  border-radius: 999px; padding: 7px 18px;
  box-shadow: 0 4px 14px rgba(51, 112, 255, .16);
  transition: filter .18s, transform .18s;
}
.qa-more:hover { filter: brightness(1.06); transform: translateY(-1px); }
.qa-more span { font-size: 15px; line-height: 1; }
.qa-len { font-size: 12px; color: var(--fg3); }
.empty { padding: 44px 0; text-align: center; color: var(--fg3); font-size: 14.5px; }
.empty[hidden] { display: none; }

/* ===== 列表卡片（链接式，manifest 驱动） ===== */
.qa { padding: 4px 0; }
a.qa-q {
  display: block; padding: 19px 40px 12px 0; position: relative;
  font-size: 16.5px; font-weight: 600; line-height: 1.6; color: var(--fg);
}
a.qa-q::after {
  content: ""; position: absolute; right: 8px; top: 26px;
  width: 8px; height: 8px; border-right: 1.8px solid var(--fg3); border-bottom: 1.8px solid var(--fg3);
  transform: rotate(-45deg); transition: transform .2s, border-color .2s;
}
a.qa-q:hover { color: var(--bl); }
a.qa-q:hover::after { border-color: var(--bl); transform: rotate(-45deg) translate(2px, -2px); }
.qa-var { border-bottom: 1px solid var(--line); }
.qa-var a.qa-q { padding-bottom: 6px; }
.qa-hub .qa-sum { margin-top: 2px; }

/* ===== 分页 ===== */
.pager { display: flex; align-items: center; gap: 6px; flex-wrap: wrap; padding: 8px 0 60px; justify-content: center; }
.pg {
  min-width: 36px; height: 36px; padding: 0 11px; border: 1px solid var(--line2);
  background: #fff; color: var(--fg2); border-radius: 8px; cursor: pointer;
  font-family: inherit; font-size: 13.5px; transition: all .15s;
}
.pg:hover:not(:disabled):not(.on) { border-color: var(--bl); color: var(--bl); }
.pg.on { background: var(--bl); border-color: var(--bl); color: #fff; }
.pg:disabled { opacity: .4; cursor: not-allowed; }
.pg-dot { color: var(--fg3); padding: 0 2px; }
.pg-info { margin-left: 10px; font-size: 12.5px; color: var(--fg3); }
@media (max-width: 640px) { .pg-info { width: 100%; text-align: center; margin: 6px 0 0; } }

/* ===== 文章页 ===== */
.crumb { padding: 26px 0 0; font-size: 12.5px; color: var(--fg3); display: flex; gap: 7px; flex-wrap: wrap; }
.crumb a:hover { color: var(--bl); }
.crumb i { font-style: normal; opacity: .5; }
.art { padding: 18px 0 24px; }
.art h1 { font-size: 28px; line-height: 1.45; letter-spacing: -.2px; color: var(--fg); }
/* 官方样式的发布信息行 */
.art-meta {
  margin-top: 18px; padding-bottom: 22px; border-bottom: 1px solid var(--line);
  font-size: 13.5px; color: var(--fg3); display: flex; gap: 22px; flex-wrap: wrap;
  font-feature-settings: "tnum";
}
.art-lead {
  margin: 26px 0 6px; padding: 17px 20px;
  background: var(--bg2); border-left: 3px solid var(--bl); border-radius: 0 8px 8px 0;
  color: var(--fg2); font-size: 15px;
}
.art-lead b { color: var(--fg); font-weight: 600; display: block; margin-bottom: 5px; font-size: 13px; letter-spacing: .3px; }

/* 目录 */
.toc { margin: 24px 0 6px; padding: 16px 20px; background: var(--bg2); border: 1px solid var(--line); border-radius: 10px; }
.toc b { display: block; font-size: 12.5px; color: var(--fg3); letter-spacing: .5px; margin-bottom: 8px; }
.toc ol { list-style: none; counter-reset: t; }
.toc li { counter-increment: t; font-size: 14px; padding: 3px 0 3px 24px; position: relative; }
.toc li::before {
  content: counter(t); position: absolute; left: 0; top: 3px;
  font-size: 11.5px; color: var(--bl); font-family: Consolas, monospace;
}
.toc a { color: var(--fg2); }
.toc a:hover { color: var(--bl); }

.doc { padding: 12px 0 30px; }
.doc > * { max-width: 78ch; }
.doc h2 {
  font-size: 20px; margin: 40px 0 14px; letter-spacing: -.1px; color: var(--fg);
  padding-left: 13px; border-left: 3px solid var(--bl); line-height: 1.45;
  scroll-margin-top: 78px;
}
.doc h3 { font-size: 16.5px; margin: 26px 0 10px; color: var(--fg); }
.doc p { margin: 15px 0; color: var(--fg2); }
.doc strong { color: var(--fg); font-weight: 600; }
.doc em { color: var(--bl); font-style: normal; }
.doc a { color: var(--bl); border-bottom: 1px solid rgba(51, 112, 255, .3); }
.doc a:hover { border-bottom-color: var(--bl); }
.doc code {
  background: var(--bg3); color: #0b4ad6; font-size: .875em;
  padding: 2px 6px; border-radius: 4px;
}
.doc kbd {
  background: #fff; border: 1px solid var(--line2); border-bottom-width: 2px;
  color: var(--fg); font-size: .82em; padding: 2px 7px; border-radius: 5px; white-space: nowrap;
}
.doc ul { margin: 15px 0; }
.doc ul li { position: relative; padding-left: 19px; margin: 9px 0; color: var(--fg2); }
.doc ul li::before {
  content: ""; position: absolute; left: 3px; top: 13px;
  width: 5px; height: 5px; border-radius: 50%; background: var(--bl);
}
/* 有序步骤 */
.doc ol.steps { margin: 18px 0; counter-reset: s; }
.doc ol.steps > li {
  counter-increment: s; position: relative; padding-left: 38px;
  margin: 14px 0; color: var(--fg2);
}
.doc ol.steps > li::before {
  content: counter(s); position: absolute; left: 0; top: 2px;
  width: 25px; height: 25px; border-radius: 50%;
  background: var(--bl-dim); border: 1px solid rgba(51, 112, 255, .35);
  color: var(--bl); font-size: 12.5px; font-weight: 600;
  display: flex; align-items: center; justify-content: center;
  font-family: Consolas, monospace;
}
.doc figure { margin: 28px 0; max-width: 100%; }
.doc figure img, .doc figure svg {
  border-radius: 10px; border: 1px solid var(--line); background: var(--bg2);
  margin: 0 auto; width: 100%; height: auto;
}
.doc figcaption { margin-top: 11px; font-size: 12.5px; color: var(--fg3); text-align: center; line-height: 1.65; }
.doc blockquote {
  margin: 22px 0; padding: 15px 19px; background: var(--bg2);
  border-left: 3px solid var(--line2); border-radius: 0 8px 8px 0;
  color: var(--fg2); font-size: 14.5px; white-space: pre-line;
}
.doc pre {
  margin: 20px 0; padding: 16px 18px; background: #0f172b;
  border: 1px solid #1c2740; border-radius: 10px;
  overflow-x: auto; font-size: 13px; line-height: 1.75; color: #d8dee9;
}
.doc pre code { background: none; color: inherit; padding: 0; }
.doc .note {
  margin: 26px 0; padding: 14px 18px; background: var(--bl-dim);
  border: 1px solid rgba(51, 112, 255, .2); border-radius: 10px;
  font-size: 13.5px; color: var(--fg2);
}
.doc .note b { color: var(--bl); font-weight: 600; }
.doc .warn {
  margin: 26px 0; padding: 14px 18px; background: rgba(245, 63, 63, .05);
  border: 1px solid rgba(245, 63, 63, .2); border-radius: 10px;
  font-size: 13.5px; color: var(--fg2);
}
.doc .warn b { color: #e04141; font-weight: 600; }

/* 表格 */
.doc .tw { margin: 22px 0; overflow-x: auto; max-width: 100%; }
.doc table { border-collapse: collapse; width: 100%; font-size: 14px; min-width: 460px; }
.doc th, .doc td {
  border: 1px solid var(--line); padding: 10px 13px;
  text-align: left; vertical-align: top; line-height: 1.65;
}
.doc th { background: var(--bg3); font-weight: 600; color: var(--fg); white-space: nowrap; }
.doc td { color: var(--fg2); }
.doc tbody tr:nth-child(even) td { background: #fafbfe; }

/* 相关问题 */
.rel { border-top: 1px solid var(--line); padding: 26px 0 0; }
.rel b { display: block; font-size: 12.5px; color: var(--fg3); letter-spacing: .5px; margin-bottom: 12px; }
.rel ul { display: flex; flex-direction: column; gap: 2px; }
.rel a { display: block; padding: 8px 0; font-size: 14.5px; color: var(--fg2); }
.rel a:hover { color: var(--bl); }
.rel a::before { content: "· "; color: var(--fg3); }

/* 文章页脚导航 */
.art-nav { border-top: 1px solid var(--line); margin-top: 26px; padding: 26px 0 60px; display: flex; gap: 12px; flex-wrap: wrap; }
.art-nav a {
  flex: 1 1 46%; min-width: 240px; background: var(--bg2);
  border: 1px solid var(--line); border-radius: 10px; padding: 14px 17px;
  transition: border-color .18s, background .18s, box-shadow .18s;
}
.art-nav a:hover { border-color: var(--bl); background: #fff; box-shadow: 0 6px 18px rgba(51, 112, 255, .1); }
.art-nav .k { font-size: 11.5px; color: var(--fg3); letter-spacing: .5px; }
.art-nav .v { margin-top: 5px; font-size: 14.5px; color: var(--fg); line-height: 1.55; }
.art-nav .home { flex-basis: 100%; text-align: center; }

/* ===== 页脚 ===== */
.ft { background: var(--navy); margin-top: 10px; }
.ft-in { max-width: var(--maxw); margin: 0 auto; padding: 32px 20px 44px; }
.ft p { font-size: 12.5px; color: #9ea4b4; line-height: 1.85; max-width: 80ch; }
.ft p + p { margin-top: 9px; }
.ft a { color: #c8cede; border-bottom: 1px solid #2b3550; }
.ft a:hover { color: #fff; }

/* ===== 响应式 ===== */
@media (max-width: 640px) {
  body { font-size: 15.5px; }
  .hero { padding: 34px 0 22px; }
  .hero h1 { font-size: 24px; }
  .art h1 { font-size: 22px; }
  .art-meta { gap: 6px 16px; font-size: 12.5px; }
  .doc h2 { font-size: 18px; margin: 32px 0 12px; }
  .qa-q { font-size: 15.5px; padding: 16px 34px 16px 0; }
  .qa-tag { display: none; }
  .art-nav a { flex-basis: 100%; }
  .brand span { display: none; }
}
@media print {
  .hd, .tools, .art-nav, .qa-more, .toc { display: none; }
  body { color: #000; }
}