/* ==========================================================================
   Q叔PDF工具箱 · 官网样式（纸本浅色 · 深藏青 + 金）
   配色取自 qs2025.top 的 CSS 变量（--black / --gold / --gold-text / --lavender-ink）
     纸 #FAF6EF · 区块 #F3E7D8 · 深藏青 #241610 · 金 #C91F2F · 金墨 #9D1F2F
   对比度实测：正文/纸 16.2 AAA ｜ 藏青/金 7.6 AAA ｜ 金墨/纸 4.8 AA
   规则：金只做填充（按钮/标签/选中），金色当文字只有 2.1:1，不能用
   ========================================================================== */

:root {
  --ink: #241610;
  --ink-2: #4A3A2E;
  --muted: #6B5140;
  --paper: #FAF6EF;
  --paper-2: #F3E7D8;
  --card: #FFFFFF;
  --hair: #E7DCCB;
  --hair-strong: #DCC9B2;
  --accent: #9D1F2F;
  --accent-soft: rgba(201, 31, 47, .12);
  --brand: #C91F2F;
  --brand-hover: #B01A29;
  --on-brand: #FFF6EC;
  --lavender: #9D1F2F;
  --sans: "PingFang SC", "Microsoft YaHei UI", "Microsoft YaHei", "Noto Sans SC", system-ui, sans-serif;
  --serif: "Songti SC", "STSong", "SimSun", "Noto Serif SC", Georgia, "Times New Roman", serif;
  --maxw: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; background: var(--paper); color: var(--ink);
  font: 16px/1.8 var(--sans); -webkit-font-smoothing: antialiased; overflow-x: hidden;
}
img, svg { max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 32px; }

.eyebrow {
  font-size: 11.5px; letter-spacing: .22em; text-transform: uppercase;
  color: var(--muted); margin: 0;
}

/* ---------------------------------------------------------------- 顶栏 */
header.nav {
  position: sticky; top: 0; z-index: 40;
  background: rgba(248, 249, 252, .88);
  backdrop-filter: saturate(150%) blur(12px);
  border-bottom: 1px solid var(--hair);
}
.nav-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 16px 32px;
  display: flex; align-items: center; gap: 30px;
  color: var(--ink); font-size: 13.5px;
}
.nav-inner .brand { font-family: var(--serif); font-size: 17px; letter-spacing: .12em; }
.nav-inner .brand i {
  display: inline-block; width: 5px; height: 5px; border-radius: 50%;
  background: var(--accent); margin-right: 10px; vertical-align: 4px;
}
.nav-links { display: flex; gap: 26px; margin-left: auto; color: var(--muted); }
.nav-links a:hover { color: var(--ink); }
.nav-pill {
  border: 1px solid var(--brand); border-radius: 999px;
  padding: 8px 20px; font-size: 12.5px; letter-spacing: .06em;
  background: var(--brand); color: var(--on-brand);
}
.nav-pill:hover { background: var(--brand-hover); border-color: var(--brand-hover); }

/* ---------------------------------------------------------------- 首屏 */
.hero {
  position: relative; overflow: hidden; isolation: isolate;
  background: var(--paper); color: var(--ink);
  padding: 132px 0 88px; text-align: center;
}
.hero::before {
  content: ""; position: absolute; inset: 0; z-index: -2;
  background:
    radial-gradient(46% 38% at 18% 8%, rgba(201, 169, 110, .28) 0%, transparent 62%),
    radial-gradient(44% 36% at 82% 6%, rgba(91, 75, 138, .12) 0%, transparent 64%),
    radial-gradient(60% 40% at 50% 100%, rgba(201, 169, 110, .16) 0%, transparent 70%);
}
.hero::after {
  content: ""; position: absolute; inset: 0; z-index: -1; pointer-events: none;
  background-image: radial-gradient(rgba(26, 26, 46, .06) 1px, transparent 1px);
  background-size: 22px 22px;
  -webkit-mask-image: radial-gradient(ellipse at 50% 30%, #000 32%, transparent 72%);
  mask-image: radial-gradient(ellipse at 50% 30%, #000 32%, transparent 72%);
}
.grain { display: none; }

.hero .eyebrow { color: var(--accent); }
.hero h1 {
  font-family: var(--serif); font-weight: 400; letter-spacing: .01em;
  font-size: clamp(36px, 4.8vw, 68px); line-height: 1.2;
  margin: 20px auto 22px; max-width: 15em; color: var(--ink);
}
.hero h1 em { font-style: normal; color: var(--accent); }
.hero .lede {
  max-width: 34em; margin: 0 auto 10px; font-size: 16px;
  color: var(--ink-2); line-height: 1.85;
}
.hero .sub { max-width: 32em; margin: 0 auto 34px; font-size: 14px; color: var(--muted); }
.cta-row { display: flex; gap: 14px; justify-content: center; align-items: center; flex-wrap: wrap; }
.btn-pill {
  display: inline-flex; align-items: center; gap: 10px;
  border: 1px solid var(--hair-strong); border-radius: 999px;
  padding: 13px 32px; font-size: 14px; letter-spacing: .1em;
  color: var(--ink); background: var(--card);
  transition: background .18s ease, border-color .18s ease, color .18s ease;
}
.btn-pill:hover { border-color: var(--ink); background: var(--paper-2); }
.btn-pill.accent { background: var(--brand); border-color: var(--brand); color: var(--on-brand); }
.btn-pill.accent:hover { background: var(--brand-hover); border-color: var(--brand-hover); color: var(--on-brand); }
.btn-text {
  font-size: 13.5px; color: var(--muted);
  border-bottom: 1px solid var(--hair-strong); padding-bottom: 3px;
}
.btn-text:hover { color: var(--ink); border-color: var(--ink); }

.hero-meta {
  display: flex; gap: 46px; justify-content: center; margin-top: 48px;
  font-size: 11.5px; letter-spacing: .18em; color: var(--muted);
}
.hero-meta b {
  display: block; font-family: var(--serif); font-size: 22px; letter-spacing: 0; color: var(--ink);
}

.hero-shot {
  position: relative; margin: 56px auto 0; max-width: 940px;
  border-radius: 16px; padding: 10px;
  background: var(--card); border: 1px solid var(--hair);
  box-shadow: 0 30px 70px -40px rgba(26, 26, 46, .28);
}
.hero-shot img { display: block; width: 100%; border-radius: 10px; background: #fff; }
.hero-shot figcaption { margin-top: 14px; font-size: 11.5px; letter-spacing: .2em; color: var(--muted); }

/* ---------------------------------------------------------------- 通用小节 */
section { padding: 88px 0; }
.section-head { margin-bottom: 44px; max-width: 42em; }
.section-head h2 {
  font-family: var(--serif); font-weight: 400; font-size: clamp(26px, 3vw, 38px);
  line-height: 1.36; margin: 12px 0;
}
.section-head p { margin: 0; color: var(--muted); font-size: 15px; }
.rule { height: 1px; background: var(--hair); border: 0; margin: 0; }

.grid-3 {
  display: grid; grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px; background: var(--hair); border: 1px solid var(--hair);
}
.cell { background: var(--paper); padding: 30px 28px; }
.cell .num { font-family: var(--serif); font-size: 13px; color: var(--accent); letter-spacing: .12em; }
.cell h3 { font-family: var(--serif); font-weight: 400; font-size: 20px; margin: 12px 0 8px; }
.cell p { margin: 0; font-size: 14px; color: var(--muted); line-height: 1.75; }

.spec { border-top: 1px solid var(--hair-strong); }
.spec-row {
  display: grid; grid-template-columns: 1.25fr .5fr 2fr; gap: 24px;
  padding: 18px 4px; border-bottom: 1px solid var(--hair); align-items: baseline;
}
.spec-row.head {
  padding: 12px 4px; font-size: 11.5px; letter-spacing: .18em;
  color: var(--muted); border-bottom-color: var(--hair-strong);
}
.spec-row .name { font-weight: 600; font-size: 15px; }
.spec-row .state { font-size: 12.5px; color: var(--ink-2); letter-spacing: .06em; }
.spec-row .state::before { content: "✓"; color: var(--accent); margin-right: 7px; font-size: 12px; }
.spec-row .desc { font-size: 14px; color: var(--muted); }

.pair {
  display: grid; grid-template-columns: 1fr 1fr; gap: 1px;
  background: var(--hair); border: 1px solid var(--hair);
}
.pair > div { background: var(--paper); padding: 34px 32px; }
.pair h3 { font-family: var(--serif); font-weight: 400; font-size: 22px; margin: 0 0 4px; }
.pair .tag { font-size: 12px; letter-spacing: .14em; color: var(--accent); }
.pair ul { margin: 18px 0 0; padding-left: 18px; font-size: 14px; color: var(--muted); line-height: 1.9; }


/* ---------------------------------------------------------------- 首屏适用边界 / 下载哈希 / 做不到的事 */
.hero-note {
  margin: 2px auto 34px; max-width: 40em; font-size: 12.5px; line-height: 1.85;
  color: var(--muted);
}
.dl-hash {
  margin: 12px 0 0; font-size: 11px; line-height: 1.7; color: var(--muted);
  font-family: ui-monospace, Consolas, monospace; word-break: break-all;
}
.dl-hash span { color: var(--ink-2); }
.limits {
  margin-top: 28px; padding: 22px 24px;
  background: var(--paper-2); border: 1px solid var(--hair); border-radius: 12px;
}
.limits h3 {
  font-family: var(--serif); font-weight: 400; font-size: 19px;
  margin: 0 0 10px; color: var(--ink);
}
.limits ul { margin: 0; padding-left: 20px; }
.limits li { font-size: 14px; color: var(--muted); line-height: 1.95; }
.limits li b { color: var(--ink-2); font-weight: 600; }

/* ---------------------------------------------------------------- 下载 */
.dl {
  background: var(--paper-2); color: var(--ink);
  border: 1px solid var(--hair);
  border-radius: 20px; padding: 48px; position: relative; overflow: hidden;
}
.dl::before {
  content: ""; position: absolute; inset: -40% -10% auto auto; width: 60%; height: 170%;
  background: radial-gradient(circle at 60% 30%, rgba(201, 169, 110, .35), transparent 62%);
  pointer-events: none;
}
.dl > * { position: relative; }
.dl h2 { font-family: var(--serif); font-weight: 400; font-size: 32px; margin: 10px 0 8px; color: var(--ink); }
.dl p.lead { margin: 0 0 32px; font-size: 14.5px; color: var(--muted); }
.dl-grid { display: grid; grid-template-columns: 1.05fr 1fr; gap: 44px; align-items: start; }
.dl-main .ver { font-size: 12px; letter-spacing: .16em; color: var(--muted); margin-bottom: 18px; }
.dl-main .btn-pill { width: 100%; justify-content: center; }
.dl-extra { margin: 14px 0 0; font-size: 13px; color: var(--ink-2); text-align: center; }
.dl-extra b { color: var(--accent); letter-spacing: .08em; }
.dl-alt { display: block; margin-top: 16px; text-align: center; font-size: 12.5px; color: var(--muted); }
.dl-alt:hover { color: var(--ink); }
.facts { font-size: 13.5px; color: var(--ink-2); margin: 0; }
.facts dt { font-size: 11.5px; letter-spacing: .16em; color: var(--muted); margin-top: 18px; }
.facts dt:first-child { margin-top: 0; }
.facts dd { margin: 4px 0 0; }
.facts a { color: var(--accent); border-bottom: 1px solid var(--accent-soft); }
.hash {
  font-family: ui-monospace, Consolas, monospace; font-size: 11.5px;
  line-height: 1.7; word-break: break-all; color: var(--muted);
}

.dl-backup { margin-top: 30px; border-top: 1px solid var(--hair-strong); padding-top: 18px; }
.dl-backup summary { cursor: pointer; font-size: 13px; color: var(--muted); }
.dl-backup p { margin: 14px 0; font-size: 13px; color: var(--muted); line-height: 1.8; }
.dl-backup code {
  background: var(--card); border: 1px solid var(--hair);
  padding: 1px 6px; border-radius: 3px;
}
.dl-backup-row { display: flex; flex-wrap: wrap; gap: 10px; }
.dl-backup-row .btn-pill { padding: 9px 18px; font-size: 12.5px; }

/* ---------------------------------------------------------------- FAQ */
details.faq { border-bottom: 1px solid var(--hair); padding: 22px 0; }
details.faq summary {
  cursor: pointer; font-family: var(--serif); font-size: 18px; color: var(--ink);
  list-style: none; display: flex; justify-content: space-between; gap: 20px;
}
details.faq summary::-webkit-details-marker { display: none; }
details.faq summary::after { content: "+"; color: var(--muted); font-family: var(--sans); }
details.faq[open] summary::after { content: "−"; }
details.faq p { margin: 14px 0 0; font-size: 14.5px; color: var(--muted); max-width: 46em; }
details.faq code {
  background: var(--paper-2); border: 1px solid var(--hair);
  padding: 1px 6px; border-radius: 3px; font-size: 13px;
}

/* ---------------------------------------------------------------- 关于 */
.about { display: grid; grid-template-columns: 1.15fr 1fr; gap: 64px; }
.about p { font-size: 15px; color: var(--ink-2); margin: 0 0 14px; }
.kv { margin: 0; font-size: 13.5px; }
.kv div { display: flex; gap: 16px; padding: 11px 0; border-bottom: 1px solid var(--hair); }
.kv dt { color: var(--muted); min-width: 9em; letter-spacing: .06em; }
.kv dd { margin: 0; }
.kv a { color: var(--accent); border-bottom: 1px solid var(--accent-soft); }

/* ---------------------------------------------------------------- 页脚 */
footer {
  background: var(--paper-2); color: var(--muted);
  border-top: 1px solid var(--hair);
  padding: 56px 0 40px; font-size: 12.5px;
}
footer .brand-f {
  font-family: var(--serif); font-size: 22px; color: var(--ink);
  letter-spacing: .1em; margin-bottom: 14px;
}
.foot-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr; gap: 40px; }
.foot-grid p { margin: 0 0 8px; line-height: 1.8; }
.foot-grid h4 {
  font-size: 11px; letter-spacing: .2em; color: var(--muted);
  font-weight: 400; margin: 0 0 14px; text-transform: uppercase;
}
.foot-grid a { color: var(--muted); }
.foot-grid a:hover { color: var(--ink); }
.foot-bottom {
  margin-top: 44px; padding-top: 20px; border-top: 1px solid var(--hair);
  display: flex; justify-content: space-between; gap: 20px; flex-wrap: wrap;
}

/* ---------------------------------------------------------------- 隐私页 */
.doc { max-width: 880px; margin: 0 auto; padding: 60px 32px 90px; }
.doc h1 { font-family: var(--serif); font-weight: 400; font-size: 40px; margin: 0 0 10px; }
.doc h2 { font-family: var(--serif); font-weight: 400; font-size: 22px; margin: 36px 0 10px; }
.doc p, .doc li { color: var(--ink-2); font-size: 15px; }
.doc .note { color: var(--muted); font-size: 13px; }
.doc code {
  background: var(--paper-2); border: 1px solid var(--hair);
  padding: 1px 6px; border-radius: 3px; font-size: 13px;
}
.doc a { color: var(--accent); border-bottom: 1px solid var(--accent-soft); }

/* ---------------------------------------------------------------- 响应式 */
@media (max-width: 980px) {
  .wrap { padding: 0 22px; }
  .hero { padding: 104px 0 64px; }
  .hero-meta { gap: 26px; flex-wrap: wrap; }
  section { padding: 60px 0; }
  .grid-3, .pair, .dl-grid, .about, .foot-grid { grid-template-columns: minmax(0, 1fr); }
  .dl { padding: 28px 22px; }
  .spec-row { grid-template-columns: minmax(0, 1fr); gap: 6px; }
  .spec-row.head { display: none; }
  .nav-links { display: none; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

/* ---------------------------------------------------------------- 价格 */
.price-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin: 24px 0; }
.price-card {
  border: 1px solid #E1D1BB; border-radius: 14px; padding: 24px;
  background: #FFFBF5;
}
.price-card.featured { border-color: #C91F2F; box-shadow: 0 12px 40px -28px rgba(201,31,47,.5); }
.price-card h3 { margin: 0 0 4px; font-size: 15px; }
.price-num { margin: 0 0 14px; font-size: 34px; font-weight: 600; color: #241610; }
.price-num span { font-size: 14px; font-weight: 400; color: #6B5140; }
.price-card ul { margin: 0 0 18px; padding-left: 18px; font-size: 14px; line-height: 2; color: #4A3A2E; }
.howto { margin-top: 8px; border-top: 1px solid #E1D1BB; padding-top: 20px; }
.howto h3 { margin: 0 0 10px; font-size: 15px; }
.howto ol { margin: 0 0 12px; padding-left: 20px; font-size: 14px; line-height: 2; color: #4A3A2E; }
.price-note { font-size: 13px; color: #6B5140; line-height: 1.9; }
@media (max-width: 760px) {
  .price-grid { grid-template-columns: 1fr; }
}

.trial-banner {
  margin: 12px 0 20px; padding: 12px 16px; border-radius: 10px;
  background: #FFF3E8; border: 1px solid #E8C9A8;
  font-size: 14px; line-height: 1.9; color: #4A3A2E;
}
.trial-banner strong { color: #C91F2F; }

.prose { max-width: 760px; margin: 0 auto; padding: 48px 24px 24px; }
.prose h1 { font-size: 30px; margin: 0 0 8px; color: #241610; }
.prose-meta { color: #6B5140; font-size: 13px; margin: 0 0 28px; }
.prose h2 { font-size: 17px; margin: 28px 0 10px; color: #241610; }
.prose p, .prose li { font-size: 15px; line-height: 2; color: #4A3A2E; }
.prose ul { padding-left: 20px; }
.prose code { background: #F7EFE4; padding: 2px 6px; border-radius: 4px; font-size: 13px; }
.prose-back { margin-top: 32px; }
.prose-back a { color: #C91F2F; }