/* 清丝录官网样式：单文件、无框架、系统字体，首屏零额外请求。 */

/* ---------- 1. 变量与重置 ---------- */
:root {
  --brand: #2563eb;
  --brand-ink: #1447c9;
  --brand-soft: #eaf1ff;
  --free: #0f9b6c;
  --free-soft: #e6f7f0;
  --vip: #b45309;
  --vip-soft: #fdf2e2;
  --ink: #101725;
  --text: #354154;
  --muted: #6b7a90;
  --line: #e4e9f1;
  --bg: #ffffff;
  --bg-alt: #f6f8fc;
  --radius: 14px;
  --radius-sm: 9px;
  --shadow: 0 1px 2px rgba(16, 23, 37, .05), 0 12px 28px -18px rgba(16, 23, 37, .18);
  --shadow-lg: 0 2px 4px rgba(16, 23, 37, .04), 0 26px 60px -30px rgba(16, 23, 37, .26);
  --maxw: 1120px;
  --nav-h: 64px;
  --fs: 16px;
}

*,
*::before,
*::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", sans-serif;
  font-size: var(--fs);
  line-height: 1.75;
  color: var(--text);
  background: var(--bg);
  word-break: break-word;
}

h1, h2, h3, h4 {
  color: var(--ink);
  font-weight: 700;
  line-height: 1.32;
  margin: 0 0 .5em;
  letter-spacing: .01em;
}
h1 { font-size: clamp(28px, 5.2vw, 44px); }
h2 { font-size: clamp(22px, 3.4vw, 30px); }
h3 { font-size: 19px; }
h4 { font-size: 16px; }
p { margin: 0 0 1em; }
a { color: var(--brand); text-decoration: none; }
a:hover { color: var(--brand-ink); text-decoration: underline; }
ul, ol { margin: 0 0 1em; padding-left: 1.35em; }
li { margin: .3em 0; }
img, svg { max-width: 100%; height: auto; display: block; }
strong { color: var(--ink); }
table { border-collapse: collapse; width: 100%; }
hr { border: 0; border-top: 1px solid var(--line); margin: 2em 0; }

.skip {
  position: absolute; left: -9999px; top: 0; background: #fff; color: var(--ink);
  padding: 10px 16px; border-radius: 0 0 8px 0; z-index: 99;
}
.skip:focus { left: 0; }

:focus-visible { outline: 2px solid var(--brand); outline-offset: 2px; }

/* ---------- 2. 布局骨架 ---------- */
.wrap { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: 20px; }
.section { padding: 56px 0; }
.section-tight { padding: 36px 0; }
.section-alt { background: var(--bg-alt); border-block: 1px solid var(--line); }
.section-head { max-width: 760px; margin-bottom: 28px; }
.section-head p { color: var(--muted); margin: 0; }
.grid { display: grid; gap: 20px; }
.g2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.g3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.g4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.center { text-align: center; }
.eyebrow {
  display: inline-block; font-size: 13px; letter-spacing: .16em; text-transform: uppercase;
  color: var(--brand); font-weight: 700; margin-bottom: 10px;
}
.lead { font-size: 17px; color: var(--text); }
.muted { color: var(--muted); }
.small { font-size: 14px; }
.mt0 { margin-top: 0; }
.mb0 { margin-bottom: 0; }

/* ---------- 3. 顶部导航 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 20; background: rgba(255, 255, 255, .92);
  backdrop-filter: saturate(180%) blur(10px); border-bottom: 1px solid var(--line);
}
.nav {
  height: var(--nav-h); display: flex; align-items: center; gap: 18px;
}
.brand { display: flex; align-items: center; gap: 9px; color: var(--ink); font-weight: 800; font-size: 18px; }
.brand:hover { text-decoration: none; color: var(--ink); }
.brand .mark { width: 30px; height: 30px; flex: none; }
.brand small { font-weight: 600; font-size: 12px; color: var(--muted); letter-spacing: .04em; }
.nav-links { display: flex; align-items: center; gap: 4px; margin-left: auto; list-style: none; padding: 0; }
.nav-links a {
  display: block; padding: 8px 12px; border-radius: 8px; color: var(--text); font-size: 15px; font-weight: 500;
}
.nav-links a:hover { background: var(--brand-soft); color: var(--brand-ink); text-decoration: none; }
.nav-links a[aria-current=page] { color: var(--brand-ink); background: var(--brand-soft); font-weight: 700; }
.nav-cta { margin-left: 8px; }
.nav-toggle { display: none; }

@media (max-width: 940px) {
  .nav { justify-content: space-between; }
  .nav-links {
    position: absolute; top: var(--nav-h); left: 0; right: 0; flex-direction: column; align-items: stretch;
    gap: 0; background: #fff; border-bottom: 1px solid var(--line); padding: 6px 14px 14px; display: none;
  }
  .nav-open .nav-links { display: flex; }
  .nav-links a { padding: 12px 10px; border-radius: 0; border-bottom: 1px solid var(--bg-alt); }
  .nav-toggle {
    display: inline-flex; align-items: center; gap: 6px; background: none; border: 1px solid var(--line);
    border-radius: 8px; padding: 7px 11px; font: inherit; font-size: 14px; color: var(--text); cursor: pointer;
  }
  .nav-cta { display: none; }
}

/* ---------- 4. 按钮与标签 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 11px 20px; border-radius: 10px; font-size: 15px; font-weight: 700;
  border: 1px solid transparent; cursor: pointer; text-align: center;
}
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--brand); color: #fff; box-shadow: 0 8px 18px -10px rgba(37, 99, 235, .8); }
.btn-primary:hover { background: var(--brand-ink); color: #fff; }
.btn-ghost { background: #fff; color: var(--brand-ink); border-color: #cfdcf7; }
.btn-ghost:hover { background: var(--brand-soft); color: var(--brand-ink); }
.btn-lg { padding: 14px 26px; font-size: 16px; }
.btn-block { width: 100%; }
.btn-row { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; }

.chip {
  display: inline-flex; align-items: center; gap: 6px; padding: 4px 11px; border-radius: 999px;
  font-size: 13px; font-weight: 700; background: var(--free-soft); color: var(--free);
}
.chip-blue { background: var(--brand-soft); color: var(--brand-ink); }
.chip-vip { background: var(--vip-soft); color: var(--vip); }
.chip-line { background: #fff; color: var(--muted); border: 1px solid var(--line); }
.tag { display: inline-block; padding: 2px 9px; border-radius: 6px; background: var(--bg-alt); color: var(--muted); font-size: 13px; }

/* ---------- 5. 首屏 ---------- */
.hero { padding: 64px 0 44px; background:
  radial-gradient(900px 340px at 12% -8%, #eef4ff 0%, rgba(238, 240, 255, 0) 70%),
  linear-gradient(180deg, #fbfcff 0%, #fff 60%); }
.hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 44px; align-items: center; }
.hero h1 { margin-bottom: 14px; }
.hero .sub { font-size: 17.5px; color: var(--text); max-width: 33em; }
.hero ul { list-style: none; padding: 0; margin: 18px 0 24px; }
.hero ul li { position: relative; padding-left: 26px; margin: 7px 0; color: var(--text); }
.hero ul li::before {
  content: ""; position: absolute; left: 2px; top: 11px; width: 14px; height: 7px;
  border-left: 2px solid var(--free); border-bottom: 2px solid var(--free);
  transform: rotate(-45deg);
}
.hero-note { font-size: 13.5px; color: var(--muted); margin-top: 14px; }
@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; gap: 30px; }
  .hero { padding-top: 40px; }
}

/* 首屏右侧的界面示意（纯 CSS，不引图片，避免额外请求） */
.mock { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow-lg); overflow: hidden; }
.mock-bar { display: flex; align-items: center; gap: 6px; padding: 10px 14px; background: var(--bg-alt); border-bottom: 1px solid var(--line); }
.mock-bar i { width: 9px; height: 9px; border-radius: 50%; background: #d7dfeb; display: block; }
.mock-bar span { font-size: 12.5px; color: var(--muted); margin-left: 6px; }
.mock-body { padding: 16px; display: grid; gap: 12px; }
.mock-row { display: flex; justify-content: space-between; gap: 12px; padding: 11px 13px; border: 1px solid var(--line); border-radius: var(--radius-sm); background: #fff; }
.mock-row b { color: var(--ink); font-size: 14.5px; font-weight: 700; }
.mock-row em { font-style: normal; color: var(--free); font-weight: 700; font-size: 14px; }
.mock-row .k { font-size: 14px; color: var(--text); }
.mock-stat { display: flex; align-items: baseline; gap: 8px; padding: 12px 13px; border-radius: var(--radius-sm); background: var(--brand-soft); }
.mock-stat b { font-size: 22px; color: var(--brand-ink); }
.mock-tabs { display: flex; gap: 8px; }
.mock-tabs i { flex: 1; height: 8px; border-radius: 4px; background: var(--bg-alt); display: block; }

/* ---------- 6. 卡片 ---------- */
.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 22px;
  transition: box-shadow .18s ease, transform .18s ease, border-color .18s ease;
}
.card:hover { box-shadow: var(--shadow); border-color: #d8e2f2; }
.card h3 { display: flex; align-items: center; gap: 8px; margin-bottom: 8px; font-size: 17.5px; }
.card p { margin: 0; font-size: 15px; color: var(--muted); }
.card .ic { color: var(--brand); flex: none; }
.card-plain { background: transparent; border-style: dashed; }

.ico-box { width: 34px; height: 34px; border-radius: 9px; background: var(--brand-soft); display: grid; place-items: center; flex: none; }
.ic { width: 20px; height: 20px; }
.ico-box .ic { width: 19px; height: 19px; }

.steps { counter-reset: s; list-style: none; padding: 0; margin: 0; display: grid; gap: 12px; }
.steps li { counter-increment: s; position: relative; padding-left: 42px; color: var(--text); }
.steps li::before {
  content: counter(s); position: absolute; left: 0; top: 1px; width: 28px; height: 28px; border-radius: 8px;
  background: var(--brand); color: #fff; font-weight: 700; font-size: 14px; display: grid; place-items: center;
}

/* ---------- 7. 表格 ---------- */
.table-scroll { overflow-x: auto; -webkit-overflow-scrolling: touch; }
.tbl { font-size: 15px; min-width: 640px; }
.tbl caption { text-align: left; color: var(--muted); font-size: 14px; padding-bottom: 10px; }
.tbl th, .tbl td { padding: 12px 14px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
.tbl thead th { background: var(--bg-alt); color: var(--ink); font-weight: 700; position: sticky; top: var(--nav-h); }
.tbl tbody th { font-weight: 600; color: var(--ink); width: 26%; }
.tbl .group td { background: #fbfcff; color: var(--brand-ink); font-weight: 700; font-size: 14px; }
.tbl .col-free { background: #f7fdfa; }
.tbl .col-vip { background: #fffdf7; }
.tbl tr:last-child td, .tbl tr:last-child th { border-bottom: 0; }
.md-table { font-size: 15px; margin: 0 0 1.4em; }
.md-table th, .md-table td { border: 1px solid var(--line); padding: 9px 12px; }
.md-table thead th { background: var(--bg-alt); }

/* ---------- 8. 价格 ---------- */
.plans { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; }
.plan { border: 1px solid var(--line); border-radius: var(--radius); padding: 26px; background: #fff; display: flex; flex-direction: column; }
.plan-free { border-color: #b8e3d1; box-shadow: var(--shadow); }
.plan-vip { border-color: #f0d9b6; }
.plan .price { display: flex; align-items: baseline; gap: 6px; margin: 6px 0 14px; }
.plan .price b { font-size: 40px; color: var(--ink); line-height: 1; }
.plan .price span { color: var(--muted); font-size: 15px; }
.plan ul { list-style: none; padding: 0; margin: 0 0 18px; display: grid; gap: 8px; }
.plan li { padding-left: 24px; position: relative; font-size: 15px; }
.plan li::before {
  content: ""; position: absolute; left: 2px; top: 11px; width: 12px; height: 6px;
  border-left: 2px solid var(--free); border-bottom: 2px solid var(--free); transform: rotate(-45deg);
}
.plan-vip li::before { border-color: var(--vip); }
.plan .note { font-size: 13.5px; color: var(--muted); margin-top: auto; }
.terms { display: flex; flex-wrap: wrap; gap: 12px; margin: 18px 0 0; }
.term { flex: 1 1 150px; border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 14px 16px; background: var(--bg-alt); }
.term b { display: block; color: var(--ink); font-size: 20px; }
.term span { font-size: 13.5px; color: var(--muted); }
@media (max-width: 820px) { .plans { grid-template-columns: 1fr; } }

/* ---------- 9. 面包屑与页头 ---------- */
.crumbs { font-size: 14px; color: var(--muted); margin-bottom: 14px; }
.crumbs ol { list-style: none; padding: 0; margin: 0; display: flex; flex-wrap: wrap; gap: 6px; }
.crumbs li { display: flex; gap: 6px; align-items: center; margin: 0; }
.crumbs li + li::before { content: "›"; color: #b9c4d4; }
.crumbs a { color: var(--muted); }
.crumbs [aria-current] { color: var(--text); }

.page-head { padding: 34px 0 6px; }
.page-head .lead { max-width: 780px; }

/* ---------- 10. 折叠问答（原生 details，零 JS） ---------- */
.faq { display: grid; gap: 10px; }
details {
  border: 1px solid var(--line); border-radius: var(--radius-sm); background: #fff; padding: 0 18px;
}
details[open] { border-color: #cfdcf7; box-shadow: var(--shadow); }
summary {
  cursor: pointer; list-style: none; padding: 15px 0; font-weight: 700; color: var(--ink);
  display: flex; justify-content: space-between; align-items: center; gap: 14px; font-size: 16px;
}
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; color: var(--brand); font-size: 20px; font-weight: 600; flex: none; }
details[open] summary::after { content: "−"; }
.faq-a { padding: 0 0 16px; margin: 0; color: var(--text); border-top: 1px solid var(--bg-alt); }
.faq-a p { margin: 12px 0 0; }
.faq-group { margin-top: 26px; }
.faq-group h2 { font-size: 20px; margin-bottom: 12px; }

/* ---------- 11. 列表与卡片网格 ---------- */
.cards-a { display: grid; gap: 16px; }
.cards-a.n2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.cards-a.n3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.cards-a.n4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
@media (max-width: 980px) { .cards-a.n3, .cards-a.n4 { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 620px) { .cards-a.n2, .cards-a.n3, .cards-a.n4, .g2, .g3, .g4 { grid-template-columns: 1fr; } }

.item-card { display: block; border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; background: #fff; color: var(--text); }
.item-card:hover { text-decoration: none; border-color: #cfdcf7; box-shadow: var(--shadow); color: var(--text); }
.item-card h3 { margin: 0 0 8px; font-size: 18px; }
.item-card p { margin: 0; font-size: 15px; color: var(--muted); }
.item-card .meta { margin-top: 12px; font-size: 13.5px; color: var(--muted); display: flex; gap: 10px; flex-wrap: wrap; }

/* ---------- 12. 博客 ---------- */
.post-list { display: grid; gap: 0; border-top: 1px solid var(--line); }
.post-row { padding: 20px 0; border-bottom: 1px solid var(--line); display: grid; gap: 6px; }
.post-row h3 { margin: 0; font-size: 19px; }
.post-row h3 a { color: var(--ink); }
.post-row h3 a:hover { color: var(--brand-ink); }
.post-row p { margin: 0; color: var(--muted); font-size: 15px; }
.post-row .meta { font-size: 13.5px; color: var(--muted); display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
.pager { display: flex; gap: 8px; align-items: center; justify-content: center; margin-top: 26px; font-size: 15px; }
.pager a, .pager span { padding: 8px 14px; border: 1px solid var(--line); border-radius: 8px; }
.pager .now { background: var(--brand); color: #fff; border-color: var(--brand); font-weight: 700; }

/* 文章正文 */
.prose { max-width: 760px; }
.prose h2 { margin-top: 1.8em; padding-top: .2em; font-size: 23px; }
.prose h3 { margin-top: 1.5em; font-size: 18.5px; }
.prose h2, .prose h3 { scroll-margin-top: calc(var(--nav-h) + 16px); }
.prose p, .prose li { font-size: 16.5px; line-height: 1.85; }
.prose blockquote { margin: 0 0 1.4em; padding: 4px 18px; border-left: 3px solid var(--brand); background: var(--brand-soft); color: var(--text); border-radius: 0 8px 8px 0; }
.prose code { background: var(--bg-alt); padding: 2px 6px; border-radius: 5px; font-size: 15px; }
.toc { border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 16px 18px; background: #fff; margin-bottom: 26px; }
.toc b { display: block; color: var(--ink); font-size: 14px; margin-bottom: 6px; }
.toc ol { margin: 0; padding-left: 20px; font-size: 15px; }
.toc li.l3 { margin-left: 14px; list-style: none; }
.article-meta { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; color: var(--muted); font-size: 14px; margin: 6px 0 22px; }
.backlinks { display: grid; gap: 10px; margin: 26px 0; }
.article-body { overflow-wrap: anywhere; }

/* ---------- 13. 表单 ---------- */
.field { display: grid; gap: 6px; margin-bottom: 14px; }
.field label { font-size: 14.5px; color: var(--ink); font-weight: 600; }
.field input, .field select, .field textarea {
  font: inherit; font-size: 15.5px; padding: 11px 13px; border: 1px solid var(--line);
  border-radius: 10px; background: #fff; color: var(--ink); width: 100%;
}
.field textarea { min-height: 104px; resize: vertical; }
.field input:focus, .field select:focus, .field textarea:focus { border-color: var(--brand); outline: none; box-shadow: 0 0 0 3px rgba(37, 99, 235, .14); }
.hp { position: absolute; left: -9999px; width: 1px; height: 1px; overflow: hidden; }
.form-note { font-size: 13.5px; color: var(--muted); }
.alert { border: 1px solid #f5c9c9; background: #fff5f5; color: #9b2c2c; padding: 12px 14px; border-radius: var(--radius-sm); font-size: 15px; }

/* ---------- 14. CTA 条与页脚 ---------- */
.cta-band { background: linear-gradient(120deg, #14409f 0%, #2563eb 55%, #3b82f6 100%); color: #fff; border-radius: var(--radius); padding: 34px; display: grid; gap: 16px; }
.cta-band h2 { color: #fff; margin: 0; }
.cta-band p { color: #dbe7ff; margin: 0; max-width: 46em; }
.cta-band .btn-primary { background: #fff; color: var(--brand-ink); }
.cta-band .btn-ghost { background: transparent; color: #fff; border-color: rgba(255, 255, 255, .55); }
.cta-band .btn-ghost:hover { background: rgba(255, 255, 255, .12); color: #fff; }
.cta-qr { display: flex; align-items: center; gap: 12px; align-self: start; background: rgba(255, 255, 255, .92); border-radius: 12px; padding: 10px 14px; }
.cta-qr img { display: block; border-radius: 6px; }
.cta-qr span { font-size: 13px; line-height: 1.5; color: var(--brand-ink); font-weight: 600; }

.site-footer { background: #0e1626; color: #a8b4c8; padding: 48px 0 24px; margin-top: 40px; font-size: 14.5px; }
.site-footer a { color: #cdd8ea; }
.site-footer a:hover { color: #fff; }
.foot-grid { display: grid; grid-template-columns: 1.4fr repeat(3, 1fr); gap: 26px; }
.foot-grid h4 { color: #fff; font-size: 14px; letter-spacing: .06em; margin-bottom: 10px; }
.foot-grid ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 7px; }
.foot-about p { margin: 0 0 10px; max-width: 30em; }
.foot-brand { display: flex; align-items: center; gap: 9px; color: #fff; font-weight: 800; font-size: 17px; margin-bottom: 10px; }
.foot-bottom { border-top: 1px solid #22304a; margin-top: 30px; padding-top: 18px; display: flex; flex-wrap: wrap; gap: 10px 20px; justify-content: space-between; font-size: 13.5px; color: #7d8aa3; }
.foot-bottom a { color: #93a4c0; }
@media (max-width: 900px) { .foot-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 560px) { .foot-grid { grid-template-columns: 1fr; } }

/* ---------- 15. 其它 ---------- */
.split { display: grid; grid-template-columns: 1.2fr .8fr; gap: 34px; align-items: start; }
@media (max-width: 900px) { .split { grid-template-columns: 1fr; } }
.kv { display: grid; gap: 10px; }
.kv-row { display: grid; grid-template-columns: 120px 1fr; gap: 12px; font-size: 15px; }
.kv-row b { color: var(--ink); font-weight: 600; }
@media (max-width: 560px) { .kv-row { grid-template-columns: 1fr; gap: 2px; } }
.note-list { list-style: none; padding: 0; }
.note-list li { padding-left: 22px; position: relative; color: var(--muted); font-size: 14.5px; }
.note-list li::before { content: "•"; position: absolute; left: 6px; color: var(--brand); }
.qr-box { display: flex; gap: 16px; align-items: center; flex-wrap: wrap; }
.qr-frame { width: 128px; height: 128px; border: 1px dashed var(--line); border-radius: 12px; display: grid; place-items: center; text-align: center; font-size: 12.5px; color: var(--muted); padding: 8px; }
.stat-row { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.stat { border-left: 3px solid var(--brand); padding-left: 14px; }
.stat b { display: block; font-size: 22px; color: var(--ink); }
.stat span { font-size: 14px; color: var(--muted); }
@media (max-width: 820px) { .stat-row { grid-template-columns: repeat(2, 1fr); } }

@media print {
  .site-header, .site-footer, .cta-band, .pager, .nav { display: none; }
  body { color: #000; }
}