/* lirnu — 比特币入门问答 · 目录式版式 v3 */
@font-face{font-family:"Grotesk";font-style:normal;font-weight:400 800;font-display:swap;src:url(/assets/fonts/hostgrotesk-latin.woff2) format("woff2");unicode-range:U+0000-00FF,U+2000-206F,U+2190-2193,U+2212}

:root{
  --ink:#11141b;
  --ink-2:#39404d;
  --muted:#646c7a;
  --faint:#949cab;
  --line:#e3e6ec;
  --line-2:#c9cfd9;
  --bg:#ffffff;
  --tint:#f5f7fb;
  --panel:#eef1f7;
  --accent:#1f3bd6;
  --accent-ink:#152aa3;
  --accent-soft:#eef1ff;
  --c1:#1f3bd6; --c2:#c8283a; --c3:#a06a00; --c4:#0b7048; --c5:#5f3bb0;
  --c1-soft:#eef1ff; --c2-soft:#fdeff0; --c3-soft:#fdf4e3; --c4-soft:#e9f6f0; --c5-soft:#f2eefc;
  --sans:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC","Source Han Sans SC",system-ui,sans-serif;
  --disp:"Grotesk","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --wide:1200px;
  --text:760px;
  --r:8px;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:84px}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--sans);font-size:16.5px;line-height:1.8;overflow-wrap:break-word;-webkit-font-smoothing:antialiased}
img,svg{max-width:100%;height:auto}
a{color:inherit}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px}
h1,h2,h3,h4{line-height:1.3;margin:0;font-weight:700;letter-spacing:-.015em}
p{margin:0}
.skip{position:absolute;left:-9999px;top:8px;background:var(--ink);color:#fff;padding:8px 14px;border-radius:var(--r);z-index:60}
.skip:focus{left:12px}
.wrap{max-width:var(--wide);margin:0 auto;padding:0 28px}
.num{font-family:var(--disp);font-feature-settings:"tnum" 1}

/* ---------- 页头 ---------- */
.site-head{position:sticky;top:0;z-index:30;background:rgba(255,255,255,.97);backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
.site-head .wrap{display:flex;align-items:center;gap:18px;min-height:66px}
.brand{display:inline-flex;align-items:center;gap:11px;text-decoration:none;color:var(--ink);margin-right:auto}
.brand-mark{width:30px;height:20px;flex:none}
.brand-word{font-family:var(--disp);font-weight:700;font-size:20px;letter-spacing:-.035em;line-height:1}
.site-nav{display:flex;align-items:center;gap:6px}
.site-nav a{display:inline-flex;align-items:center;min-height:44px;padding:0 14px;border-radius:999px;text-decoration:none;font-size:14.5px;color:var(--ink-2)}
.site-nav a:hover{background:var(--tint);color:var(--ink)}
.site-nav a[aria-current="page"]{background:var(--ink);color:#fff;font-weight:600}
.menu-btn{display:none;align-items:center;gap:9px;min-height:44px;padding:0 14px;border:1px solid var(--line-2);border-radius:var(--r);background:#fff;color:var(--ink);font:inherit;font-size:14.5px;cursor:pointer}
.menu-btn span{display:block;width:15px;height:1.5px;background:currentColor;box-shadow:0 5px 0 currentColor,0 -5px 0 currentColor}

/* ---------- 页脚 ---------- */
.site-foot{margin-top:96px;background:var(--ink);color:#b9c0cf;font-size:14px}
.site-foot a{color:#e7eaf1;text-decoration:none}
.site-foot a:hover{color:#fff;text-decoration:underline;text-underline-offset:3px}
.foot-top{display:grid;grid-template-columns:1.6fr 1fr 1fr;gap:48px;padding:56px 0 40px}
.foot-brand{display:inline-flex;align-items:center;gap:10px;font-family:var(--disp);font-weight:700;font-size:20px;letter-spacing:-.035em;color:#fff}
.foot-brand .brand-mark{width:28px;height:19px;color:#fff}
.foot-say{margin-top:16px;max-width:34em;line-height:1.85;color:#98a1b2;font-size:13.5px}
.foot-say a{color:#c9d0de;text-decoration:underline;text-underline-offset:3px}
.foot-h{font-size:12px;font-weight:600;letter-spacing:.16em;color:#7a839a;margin-bottom:16px}
.foot-col ul{list-style:none;margin:0;padding:0;display:grid;gap:10px}
.foot-base{border-top:1px solid rgba(255,255,255,.12);padding:18px 0 32px;display:flex;flex-wrap:wrap;gap:8px 26px;justify-content:space-between;color:#7a839a;font-size:12.5px}

/* ---------- 首页 ---------- */
.hero{padding:56px 0 52px;background:
  radial-gradient(circle at 1px 1px,rgba(17,20,27,.07) 1px,transparent 0) 0 0/26px 26px,
  linear-gradient(180deg,var(--tint),#fff 88%);
  border-bottom:1px solid var(--line)}
.hero .wrap{display:grid;grid-template-columns:minmax(0,1.3fr) minmax(0,1fr);grid-template-areas:"copy ticket" "find ticket";column-gap:60px;row-gap:0;align-items:start}
.hero-copy{grid-area:copy}
.hero .ticket{grid-area:ticket}
.hero-find{grid-area:find;margin-top:32px}
.tagline{display:inline-flex;align-items:center;gap:9px;padding:6px 14px 6px 12px;border-radius:999px;background:#fff;border:1px solid var(--line);font-size:13px;font-weight:600;color:var(--ink-2);margin-bottom:22px}
.tagline::before{content:"";width:9px;height:9px;border-radius:2px;background:var(--accent)}
.hero h1{font-size:clamp(33px,4.2vw,53px);line-height:1.15;letter-spacing:-.03em}
.mk{position:relative;white-space:nowrap}
.mk-1{box-shadow:inset 0 -.28em 0 rgba(31,59,214,.16)}
.mk-2{box-shadow:inset 0 -.28em 0 rgba(17,20,27,.09)}
.hero-lede{margin-top:20px;font-size:17px;line-height:1.85;color:var(--muted);max-width:32em}
.ask{display:flex;align-items:stretch;max-width:540px;background:#fff;border:1.5px solid var(--ink);border-radius:var(--r);overflow:hidden}
.ask label{position:absolute;left:-9999px}
.ask input{flex:1;min-width:0;border:0;background:transparent;padding:0 16px;height:54px;font:inherit;font-size:16.5px;color:var(--ink)}
.ask input::placeholder{color:var(--faint)}
.ask input:focus{outline:none}
.ask:focus-within{box-shadow:0 0 0 4px rgba(31,59,214,.14)}
.ask button{border:0;background:var(--ink);color:#fff;font:inherit;font-size:15px;font-weight:600;padding:0 22px;cursor:pointer}
.ask button:hover{background:var(--accent)}
.common{margin-top:22px}
.common-label{font-size:12px;font-weight:600;letter-spacing:.16em;color:var(--faint);margin-bottom:12px}
.common ul{list-style:none;margin:0;padding:0;display:flex;flex-wrap:wrap;gap:9px}
.common a{display:inline-flex;align-items:center;min-height:42px;padding:6px 15px;border:1px solid var(--line);border-radius:999px;background:#fff;text-decoration:none;font-size:14.5px;line-height:1.4;color:var(--ink-2)}
.common a:hover{border-color:var(--accent);color:var(--accent);background:var(--accent-soft)}

.ticket{border:1px solid var(--line);border-radius:12px;background:#fff;overflow:hidden;box-shadow:0 18px 40px -30px rgba(17,20,27,.5)}
.ticket-label{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:13px 22px;background:var(--ink);color:#aab2c2;font-size:12.5px;letter-spacing:.06em}
.ticket-label b{font-weight:600;color:#fff;letter-spacing:.04em}
.ticket-main{padding:22px 22px 20px}
.ticket-code{display:flex;align-items:center;justify-content:space-between;gap:14px}
.ticket-code .num{font-size:clamp(34px,3.6vw,44px);font-weight:700;letter-spacing:.01em;line-height:1}
.copy-btn{flex:none;min-height:46px;padding:0 18px;border:0;border-radius:var(--r);background:var(--accent);color:#fff;font:inherit;font-size:14.5px;font-weight:600;cursor:pointer}
.copy-btn:hover{background:var(--accent-ink)}
.copy-btn.done{background:var(--c4)}
.copy-state{min-height:1.1em;margin-top:9px;font-size:13px;color:var(--c4)}
.ticket-gain{margin-top:16px;padding:13px 15px;border-radius:var(--r);background:var(--accent-soft);font-size:14.5px;line-height:1.8;color:#1b2a6b}
.ticket-fine{margin-top:12px;font-size:13px;line-height:1.75;color:var(--muted)}
.ticket-fine a{color:var(--ink-2);text-decoration:underline;text-underline-offset:3px}
.ticket-cut{border-top:1px solid var(--line)}
.pick{display:grid;grid-template-columns:104px minmax(0,1fr);gap:16px;align-items:start;padding:18px 22px 20px;text-decoration:none;background:var(--tint)}
.pick:hover{background:var(--panel)}
.pick-thumb{width:104px;height:55px;object-fit:cover;border:1px solid var(--line-2);border-radius:5px;background:#fff}
.pick-label{display:block;font-size:12px;font-weight:600;letter-spacing:.08em;color:var(--accent)}
.pick-title{display:block;margin-top:7px;font-size:16.5px;font-weight:700;line-height:1.5}
.pick-title::after{content:" ↗";color:var(--accent);font-family:var(--disp)}
.pick-why{display:block;margin-top:7px;font-size:13.5px;color:var(--muted);line-height:1.7}
.pick:hover .pick-title{color:var(--accent)}

/* 数据带 */
.stats-sec{background:var(--ink);color:#fff}
.stats{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(4,minmax(0,1fr))}
.stats li{padding:26px 24px 28px;border-left:1px solid rgba(255,255,255,.1)}
.stats li:first-child{border-left:0;padding-left:0}
.stats b{display:block;font-family:var(--disp);font-size:38px;font-weight:700;letter-spacing:-.03em;line-height:1}
.stats span{display:block;margin-top:9px;font-size:14px;color:#98a1b2;line-height:1.6}

[data-stage="1"]{--st:var(--c1);--st-soft:var(--c1-soft)}
[data-stage="2"]{--st:var(--c2);--st-soft:var(--c2-soft)}
[data-stage="3"]{--st:var(--c3);--st-soft:var(--c3-soft)}
[data-stage="4"]{--st:var(--c4);--st-soft:var(--c4-soft)}
[data-stage="5"]{--st:var(--c5);--st-soft:var(--c5-soft)}

.road-sec{padding:44px 0 0}
.road{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:12px;list-style:none;margin:0;padding:0}
.road a{display:grid;align-content:start;gap:8px;height:100%;padding:18px 18px 20px;text-decoration:none;background:var(--st-soft);border-radius:10px;border:1px solid transparent}
.road a:hover{border-color:var(--st)}
.road .num{display:flex;align-items:center;gap:9px;font-size:12px;font-weight:700;letter-spacing:.1em;color:var(--st)}
.road .num::before{content:"";width:10px;height:10px;border-radius:3px;background:var(--st);flex:none}
.road b{font-size:17px}
.road span{font-size:13.5px;color:var(--ink-2);line-height:1.65}

.sec-head{display:flex;flex-wrap:wrap;align-items:baseline;justify-content:space-between;gap:10px 36px;margin:76px 0 10px;padding-bottom:16px;border-bottom:2px solid var(--ink)}
.sec-head h2{font-size:clamp(23px,2.5vw,29px)}
.sec-head p{color:var(--muted);max-width:34em;font-size:15px}

.stage{display:grid;grid-template-columns:250px minmax(0,1fr);gap:40px;padding:40px 0 12px}
.stage + .stage{border-top:1px solid var(--line)}
.stage-side{position:sticky;top:96px;align-self:start}
.stage-no{display:inline-flex;align-items:center;justify-content:center;width:46px;height:46px;border-radius:10px;background:var(--st);color:#fff;font-family:var(--disp);font-size:17px;font-weight:700;letter-spacing:.02em}
.stage-side h3{margin-top:16px;font-size:24px}
.stage-side p{margin-top:10px;color:var(--muted);font-size:14.5px;line-height:1.8}
.stage-more{display:inline-flex;align-items:center;min-height:42px;margin-top:8px;font-size:14.5px;font-weight:600;color:var(--st);text-decoration:none}
.stage-more::after{content:"→";font-family:var(--disp);margin-left:8px}
.stage-more:hover{text-decoration:underline;text-underline-offset:4px}

.qlist{list-style:none;margin:0;padding:0;counter-reset:q;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));border:1px solid var(--line);border-radius:10px;overflow:hidden;background:#fff}
.qlist li{counter-increment:q;border-top:1px solid var(--line);border-left:1px solid var(--line)}
.qlist li:nth-child(-n+2){border-top:0}
.qlist li:nth-child(odd){border-left:0}
.qlist a{display:grid;grid-template-columns:34px minmax(0,1fr);grid-template-areas:"n t" "n d";column-gap:12px;height:100%;padding:16px 16px 18px;text-decoration:none}
.qlist a::before{content:counter(q,decimal-leading-zero);grid-area:n;font-family:var(--disp);font-size:12.5px;font-weight:700;color:var(--st,var(--faint));padding-top:4px}
.qlist a:hover{background:var(--st-soft,var(--tint))}
.qlist a:hover .q-title{color:var(--st,var(--accent))}
.q-title{grid-area:t;display:block;font-size:16.5px;font-weight:600;line-height:1.55}
.q-desc{grid-area:d;display:block;margin-top:6px;font-size:14px;color:var(--muted);line-height:1.7}
.q-sec{display:inline-block;margin-top:8px;padding:2px 9px;border-radius:999px;background:var(--panel);font-size:12.5px;color:var(--ink-2)}

.tool-row{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px;margin-top:26px}
.tool-card{display:grid;grid-template-rows:auto auto 1fr auto;gap:12px;padding:26px;border:1px solid var(--line);border-radius:10px;text-decoration:none;background:#fff}
.tool-card:hover{border-color:var(--accent);box-shadow:0 14px 30px -24px rgba(31,59,214,.6)}
.tool-card b{font-size:18px;line-height:1.5}
.tool-card span{color:var(--muted);font-size:14.5px;line-height:1.75}
.tool-card code{display:block;padding:13px 15px;border-radius:var(--r);background:var(--ink);color:#c9d0de;font-family:var(--disp);font-size:13px;line-height:1.7}
.tool-card code em{font-style:normal;color:#8fa3ff;font-weight:600}

.ways{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px;margin-top:26px}
.ways > div{padding:24px 26px 26px;background:var(--tint);border-radius:10px}
.ways h3{font-size:17px}
.ways h3::before{content:"";display:block;width:26px;height:4px;border-radius:2px;background:var(--accent);margin-bottom:14px}
.ways p{margin-top:10px;color:var(--muted);font-size:14.5px;line-height:1.8}
.ways-links{margin-top:22px;font-size:14.5px;color:var(--muted)}
.ways-links a{color:var(--ink-2);text-decoration:underline;text-underline-offset:4px}
.ways-links a:hover{color:var(--accent)}

/* ---------- 列表 / 分类 ---------- */
.list-head{padding:44px 0 10px;max-width:56em}
.list-head h1{font-size:clamp(29px,3.5vw,42px);letter-spacing:-.03em}
.list-head p{margin-top:16px;color:var(--muted);font-size:16px;line-height:1.85}
.list-head .breadcrumb{padding:0 0 20px}
.list-body{max-width:1000px}
.list-group{margin-top:44px}
.list-group h2{display:flex;align-items:center;gap:14px;font-size:21px;margin-bottom:14px}
.list-group h2 .num{display:inline-flex;align-items:center;justify-content:center;width:40px;height:40px;border-radius:9px;background:var(--st);color:#fff;font-size:15px;font-weight:700}
.list-group h2 a{text-decoration:none}
.list-group h2 a:hover{color:var(--st);text-decoration:underline;text-underline-offset:5px}
.band{height:6px;width:84px;border-radius:3px;background:var(--st);margin:0 0 24px}
.other-stages{display:flex;flex-wrap:wrap;gap:10px;margin-top:46px;padding-top:28px;border-top:1px solid var(--line)}
.other-stages a{display:inline-flex;align-items:center;gap:10px;min-height:44px;padding:0 16px;border-radius:999px;background:var(--st-soft);text-decoration:none;font-size:14.5px;color:var(--ink-2)}
.other-stages a::before{content:"";width:10px;height:10px;border-radius:3px;background:var(--st);flex:none}
.other-stages a:hover{color:var(--st)}

/* ---------- 文章 ---------- */
.doc{max-width:calc(var(--text) + 56px);margin:0 auto;padding:0 28px}
.breadcrumb{padding-top:26px;font-size:13px;color:var(--faint);line-height:1.7}
.breadcrumb a{color:var(--muted);text-decoration:none}
.breadcrumb a:hover{color:var(--accent);text-decoration:underline}
.breadcrumb span[aria-hidden]{margin:0 7px;color:var(--line-2)}
.art-head{margin-top:22px;padding:26px 28px 24px;background:var(--tint);border-radius:12px;border-left:5px solid var(--line-2)}
.doc:has(.eyebrow a[href$="understand.html"]) .art-head{border-left-color:var(--c1);background:linear-gradient(180deg,var(--c1-soft),var(--tint) 70%)}
.doc:has(.eyebrow a[href$="trust.html"]) .art-head{border-left-color:var(--c2);background:linear-gradient(180deg,var(--c2-soft),var(--tint) 70%)}
.doc:has(.eyebrow a[href$="cost.html"]) .art-head{border-left-color:var(--c3);background:linear-gradient(180deg,var(--c3-soft),var(--tint) 70%)}
.doc:has(.eyebrow a[href$="buy.html"]) .art-head{border-left-color:var(--c4);background:linear-gradient(180deg,var(--c4-soft),var(--tint) 70%)}
.doc:has(.eyebrow a[href$="#after"]) .art-head{border-left-color:var(--c5);background:linear-gradient(180deg,var(--c5-soft),var(--tint) 70%)}
.eyebrow{font-size:13px}
.eyebrow a{display:inline-flex;align-items:center;gap:9px;padding:5px 13px 5px 11px;border-radius:999px;background:#fff;border:1px solid var(--line);text-decoration:none;font-weight:600;color:var(--ink-2)}
.eyebrow a::before{content:"";width:9px;height:9px;border-radius:2px;background:var(--faint);flex:none}
.eyebrow a:hover{color:var(--accent);border-color:var(--accent)}
.eyebrow a[href$="understand.html"]::before{background:var(--c1)}
.eyebrow a[href$="trust.html"]::before{background:var(--c2)}
.eyebrow a[href$="cost.html"]::before{background:var(--c3)}
.eyebrow a[href$="buy.html"]::before{background:var(--c4)}
.eyebrow a[href$="#after"]::before{background:var(--c5)}
.art-head h1{margin-top:16px;font-size:clamp(28px,3.2vw,38px);line-height:1.3;letter-spacing:-.028em}
.dek{margin-top:16px;font-size:17px;line-height:1.85;color:var(--ink-2)}
.meta{margin-top:20px;padding-top:15px;border-top:1px solid var(--line-2);display:flex;flex-wrap:wrap;gap:4px 20px;font-size:12.5px;color:var(--muted)}
.meta a{color:var(--muted)}
.cover{margin:26px 0 0}
.cover img{display:block;width:100%;border:1px solid var(--line);border-radius:10px}

.art-body{margin-top:34px;font-size:17px;line-height:1.9;color:#1b1f28}
.art-body > * + *{margin-top:1.1em}
.art-body h2{margin-top:2.5em;font-size:24px;color:var(--ink);scroll-margin-top:88px;padding-left:16px;border-left:5px solid var(--accent)}
.art-body h3{margin-top:1.9em;font-size:18.5px;color:var(--ink)}
.art-body h2 + *,.art-body h3 + *{margin-top:.8em}
.art-body ul,.art-body ol{padding-left:1.35em}
.art-body li{padding-left:2px}
.art-body li + li{margin-top:.5em}
.art-body li::marker{color:var(--faint)}
.art-body a{color:var(--accent);text-decoration:underline;text-decoration-thickness:1px;text-underline-offset:3px}
.art-body a:hover{color:var(--accent-ink);text-decoration-thickness:2px}
.art-body strong{color:var(--ink);font-weight:600}
.art-body blockquote{margin:1.6em 0;padding:14px 20px;border-left:4px solid var(--line-2);background:var(--tint);border-radius:0 var(--r) var(--r) 0;color:var(--ink-2)}
.art-body hr{border:0;border-top:1px solid var(--line);margin:2.4em 0}
.ui{display:inline-block;padding:1px 8px;border:1px solid var(--line-2);border-radius:5px;background:#fff;box-shadow:0 1px 0 var(--line-2);font-size:.88em;line-height:1.6;white-space:nowrap;color:var(--ink)}
.table-scroll{overflow-x:auto;-webkit-overflow-scrolling:touch;border:1px solid var(--line);border-radius:10px}
.art-body table{width:100%;border-collapse:collapse;font-size:15px;line-height:1.7;background:#fff}
.art-body th,.art-body td{padding:12px 16px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line)}
.art-body thead th{background:var(--tint);font-size:13.5px;font-weight:700;color:var(--ink);white-space:nowrap;border-bottom:1px solid var(--line-2)}
.art-body tbody tr:last-child td{border-bottom:0}
.art-body tbody tr:hover{background:var(--tint)}
.table-scroll table{min-width:560px}

.toc{padding:20px 24px;border-radius:10px;background:var(--tint);border-left:5px solid var(--ink)}
.toc-title{font-size:12px;font-weight:700;letter-spacing:.16em;color:var(--muted)}
.toc ol{margin:12px 0 0;padding-left:1.35em;font-size:15.5px;line-height:1.85;color:var(--muted)}
.toc li + li{margin-top:2px}
.toc a{text-decoration:none;color:var(--ink-2)}
.toc a:hover{color:var(--accent);text-decoration:underline;text-underline-offset:4px}

.answer{padding:22px 24px;border-radius:10px;background:var(--accent-soft);border-left:5px solid var(--accent)}
.answer-label{display:block;font-size:12px;font-weight:700;letter-spacing:.14em;color:var(--accent);margin-bottom:9px}
.answer p{font-size:17.5px;line-height:1.85;color:#161c33}
.answer p + p{margin-top:.6em}
.tldr{padding:22px 24px;border-radius:10px;background:#fff;border:1px solid var(--line-2);box-shadow:0 12px 26px -24px rgba(17,20,27,.6)}
.tldr-label{display:block;font-size:12px;font-weight:700;letter-spacing:.14em;color:var(--muted)}
.tldr ul{margin:12px 0 0;padding-left:1.2em}
.warn{padding:20px 24px;border-radius:10px;background:var(--c2-soft);border-left:5px solid var(--c2)}
.warn strong{color:#8e1a29}
.warn-label{display:block;font-size:12px;font-weight:700;letter-spacing:.14em;color:var(--c2);margin-bottom:8px}
.misread{padding:22px 24px;border-radius:10px;background:var(--panel);border-left:5px solid var(--line-2)}
.misread-label{display:block;font-size:12px;font-weight:700;letter-spacing:.14em;color:var(--ink-2);margin-bottom:8px}
.note{padding:14px 18px;border-radius:var(--r);background:var(--tint);font-size:15.5px;line-height:1.8;color:var(--muted)}
.scene{padding:20px 24px;border-radius:10px;border:1px dashed var(--line-2);background:#fff;font-size:16.5px;color:var(--ink-2)}
.scene p + p{margin-top:.55em}
.src{margin-top:2.6em;padding:16px 20px;border-radius:var(--r);background:var(--tint);font-size:13.5px;line-height:1.85;color:var(--muted)}
.src a{color:var(--ink-2)}

.steps{list-style:none;padding:0!important;counter-reset:st;display:grid;gap:12px}
.steps > li{position:relative;counter-increment:st;padding:20px 22px 20px 62px;border:1px solid var(--line);border-radius:10px;background:#fff}
.steps > li + li{margin-top:0}
.steps > li::before{content:counter(st,decimal-leading-zero);position:absolute;left:20px;top:20px;display:flex;align-items:center;justify-content:center;width:28px;height:28px;border-radius:7px;background:var(--ink);color:#fff;font-family:var(--disp);font-size:12.5px;font-weight:700}
.steps > li > b:first-child{display:block;font-size:17px;color:var(--ink)}
.done{display:block;margin-top:12px;padding:9px 13px;border-radius:var(--r);background:var(--c4-soft);border-left:4px solid var(--c4);font-size:15px;line-height:1.7;color:#0e5236}
.done::before{content:"看到这个算完成：";font-weight:700}

.decide{padding:0}
.decide ol{list-style:none;padding:0;margin:0;display:grid;gap:10px}
.decide > ol > li{padding:16px 20px;border-radius:10px;background:var(--tint);border-left:4px solid var(--accent)}
.decide > ol > li + li{margin-top:0}
.decide .if{display:block;font-weight:700;color:var(--ink)}
.decide .then{display:block;margin-top:7px;color:var(--ink-2)}

.timeline{list-style:none;padding:0!important;margin-left:7px;border-left:2px solid var(--line-2)}
.timeline li{position:relative;padding:0 0 22px 26px}
.timeline li::before{content:"";position:absolute;left:-8px;top:8px;width:14px;height:14px;border-radius:4px;background:#fff;border:3px solid var(--accent)}
.timeline .when{display:block;font-family:var(--disp);font-size:12px;font-weight:700;letter-spacing:.1em;color:var(--accent)}

.calc{padding:24px 26px;border-radius:10px;background:var(--ink);color:#d7dce6}
.calc-label{display:block;font-size:12px;font-weight:700;letter-spacing:.12em;color:#8fa3ff;margin-bottom:12px}
.calc p + p{margin-top:.55em}
.calc strong{color:#fff}
.calc .eq{display:block;margin:12px 0;padding:12px 16px;border-radius:var(--r);background:rgba(255,255,255,.08);font-family:var(--disp);font-size:15px;color:#fff}

.compare{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}
.compare > div{padding:20px 22px 22px;border:1px solid var(--line);border-radius:10px;background:#fff}
.compare > div:first-child{border-top:4px solid var(--accent)}
.compare > div:last-child{border-top:4px solid var(--c3)}
.compare h3{margin-top:0;font-size:17px}
.compare ul{margin-top:10px}

.shot{margin:2em 0}
.shot img{display:block;width:100%;border:1px solid var(--line);border-radius:10px}
.shot figcaption{margin-top:12px;padding-left:14px;border-left:3px solid var(--line-2);font-size:13.5px;line-height:1.75;color:var(--muted)}
.diagram{margin:2em 0;padding:22px;border:1px solid var(--line);border-radius:10px;background:var(--tint)}
.diagram svg{display:block;width:100%;height:auto}
.diagram figcaption{margin-top:14px;font-size:13.5px;color:var(--muted)}

.go-next{padding:22px 24px;border-radius:10px;background:var(--ink);color:#d7dce6}
.go-next-label{display:block;font-size:12px;font-weight:700;letter-spacing:.14em;color:#8fa3ff;margin-bottom:9px}
.go-next p + p{margin-top:.6em}
.go-next a{color:#fff;font-weight:600;text-decoration-color:rgba(255,255,255,.5)}
.go-next a:hover{color:#fff}

.reg-link{padding:22px 24px;border-radius:10px;border:1px solid var(--c4);background:var(--c4-soft)}
.reg-link a{font-weight:700}
.reg-link small{display:block;margin-top:12px;font-size:13px;line-height:1.75;color:#2c5546}

.faq{margin-top:64px}
.faq h2{font-size:22px;margin-bottom:12px;padding-left:16px;border-left:5px solid var(--ink)}
.faq details{border:1px solid var(--line);border-radius:10px;background:#fff;margin-bottom:10px}
.faq summary{display:flex;justify-content:space-between;gap:16px;padding:16px 20px;font-size:16.5px;font-weight:600;cursor:pointer;list-style:none}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";font-family:var(--disp);font-weight:400;color:var(--accent);flex:none}
.faq details[open]{background:var(--tint)}
.faq details[open] summary::after{content:"−"}
.faq details p{padding:0 20px 18px;font-size:16px;line-height:1.85;color:var(--ink-2)}

.related{margin-top:64px;padding:26px;border-radius:12px;background:var(--tint)}
.related h2{font-size:12px;font-weight:700;letter-spacing:.16em;color:var(--muted)}
.related ul{list-style:none;margin:14px 0 0;padding:0;display:grid;gap:10px}
.related a{display:flex;align-items:center;justify-content:space-between;gap:14px;min-height:48px;padding:12px 16px;border-radius:var(--r);background:#fff;border:1px solid var(--line);text-decoration:none;font-size:16px;font-weight:600;line-height:1.5}
.related a::after{content:"→";font-family:var(--disp);color:var(--faint);flex:none}
.related a:hover{border-color:var(--accent);color:var(--accent)}
.related a:hover::after{color:var(--accent)}

.stuck{max-width:calc(var(--text) + 56px);margin:44px auto 0;padding:0 28px}
.stuck-in{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:16px 28px;align-items:center;padding:24px 26px;border-radius:12px;border:1px dashed var(--line-2);background:#fff}
.stuck h2{font-size:17px}
.stuck p{margin-top:8px;font-size:14px;line-height:1.8;color:var(--muted)}
.stuck a.mail{display:inline-flex;align-items:center;min-height:46px;padding:0 20px;border-radius:var(--r);background:var(--ink);color:#fff;text-decoration:none;font-size:14.5px;font-weight:600;white-space:nowrap}
.stuck a.mail:hover{background:var(--accent)}

/* ---------- 工具 ---------- */
.tool-head{padding:42px 0 10px;max-width:56em}
.tool-head .breadcrumb{padding:0 0 20px}
.tool-head h1{font-size:clamp(27px,3.3vw,38px);line-height:1.3;letter-spacing:-.028em}
.tool-head p{margin-top:16px;color:var(--muted);font-size:16px;line-height:1.85}
.tool{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:24px;margin-top:30px;align-items:start}
.panel{padding:26px;border:1px solid var(--line);border-radius:12px;background:#fff}
.panel h2{font-size:12px;font-weight:700;letter-spacing:.16em;color:var(--muted);margin-bottom:20px}
.field + .field{margin-top:18px}
.field label,.field .label-like{display:block;font-size:14.5px;font-weight:600;margin-bottom:8px}
.field .hint{display:block;margin-top:8px;font-size:13px;line-height:1.7;color:var(--muted);font-weight:400}
.field input,.field select{width:100%;height:50px;padding:0 14px;border:1px solid var(--line-2);border-radius:var(--r);background:#fff;font:inherit;font-size:16.5px;color:var(--ink);font-family:var(--disp),var(--sans)}
.field input:focus,.field select:focus{outline:none;border-color:var(--accent);box-shadow:0 0 0 3px rgba(31,59,214,.14)}
.seg{display:flex;flex-wrap:wrap;gap:8px}
.seg label{display:inline-flex;align-items:center;gap:8px;min-height:44px;padding:0 15px;border:1px solid var(--line-2);border-radius:999px;font-weight:400;cursor:pointer;margin:0;font-size:14.5px}
.seg input{width:auto;height:auto;accent-color:var(--accent)}
.seg label:has(input:checked){border-color:var(--accent);background:var(--accent-soft);color:var(--accent);font-weight:600}
.result{padding:28px;border-radius:12px;background:var(--ink);color:#d7dce6;position:sticky;top:96px}
.result h2{font-size:12px;font-weight:700;letter-spacing:.16em;color:#8994a8}
.big{margin-top:14px;font-family:var(--disp);font-size:clamp(28px,3.5vw,40px);font-weight:700;line-height:1.15;color:#fff;word-break:break-all;letter-spacing:-.03em}
.big small{font-size:.42em;font-weight:500;color:#98a1b2;margin-left:8px;letter-spacing:0}
.result dl{margin:24px 0 0;display:grid;gap:0}
.result dl div{display:flex;justify-content:space-between;gap:16px;padding:12px 0;border-top:1px solid rgba(255,255,255,.12);font-size:14.5px}
.result dt{color:#98a1b2}
.result dd{margin:0;font-family:var(--disp);font-size:14px;color:#fff;text-align:right;word-break:break-all}
.result .flag{margin-top:18px;padding:12px 14px;border-radius:var(--r);background:rgba(143,163,255,.16);color:#c3ccff;font-size:13.5px;line-height:1.75}
.result .flag:empty{display:none}
.result .sub{margin-top:10px;font-size:14px;color:#98a1b2;word-break:break-all}
.chips{display:flex;flex-wrap:wrap;gap:8px;margin-top:16px}
.chip{min-height:44px;padding:0 14px;border:1px solid var(--line-2);border-radius:999px;background:#fff;font:inherit;font-size:13.5px;color:var(--ink-2);cursor:pointer;font-family:var(--disp),var(--sans)}
.chip:hover{border-color:var(--accent);color:var(--accent);background:var(--accent-soft)}
.demo-btn{margin-top:20px;min-height:44px;padding:0 16px;border:1px dashed var(--line-2);border-radius:var(--r);background:transparent;font:inherit;font-size:14px;color:var(--muted);cursor:pointer}
.demo-btn:hover{border-color:var(--accent);color:var(--accent)}
.guide{max-width:var(--text);margin-top:56px}
.guide > details{border:1px solid var(--line);border-radius:12px;background:#fff}
.guide > details[open]{background:var(--tint)}
.guide > details > summary{padding:20px 24px;font-size:16.5px;font-weight:700;cursor:pointer}
.guide .art-body{margin-top:0;padding:0 24px 26px}
.guide .art-body h2{margin-top:0}
.tool-hub{display:grid;gap:20px;margin-top:30px;max-width:900px}
.tool-hub .tool-card{grid-template-rows:none}

/* ---------- 搜索 ---------- */
.find{max-width:880px}
.find .ask{max-width:none;margin-top:24px}
.find-state{margin-top:24px;color:var(--muted);font-size:14.5px}
.find-list{list-style:none;margin:18px 0 0;padding:0;display:grid;gap:10px;grid-template-columns:1fr;border:0;background:none;counter-reset:q}
.find-list li{border:1px solid var(--line);border-radius:10px;background:#fff}
.find-list li:nth-child(-n+2){border-top:1px solid var(--line)}
.find-list a{display:block;padding:16px 20px}
.find-list a::before{content:none}
.find-list a:hover{background:var(--tint);border-radius:10px}
.find-list a:hover .q-title{color:var(--accent)}
.find-list .q-title,.find-list .q-desc{grid-area:auto}
.find-empty{margin-top:24px;padding:24px 26px;border-radius:12px;background:var(--tint)}
.find-empty ul{margin:12px 0 0;padding-left:1.2em}
.find-empty a{color:var(--accent)}

/* ---------- 普通说明页 ---------- */
.plain{max-width:calc(var(--text) + 56px);margin:0 auto;padding:48px 28px 0}
.plain h1{font-size:clamp(28px,3.3vw,37px);letter-spacing:-.028em}
.plain .dek{margin-top:16px;color:var(--muted)}
.plain .art-body{margin-top:32px}
.fix-log{list-style:none;padding:0!important;display:grid;gap:12px}
.fix-log li{padding:20px 22px;border:1px solid var(--line);border-radius:10px;background:#fff}
.fix-log li + li{margin-top:0}
.fix-log time{display:inline-block;padding:3px 10px;border-radius:999px;background:var(--panel);font-family:var(--disp);font-size:12.5px;font-weight:600;color:var(--ink-2);margin-bottom:10px}

.lost{max-width:660px;margin:0 auto;padding:84px 28px 0}
.lost .num{font-size:78px;font-weight:700;line-height:1;color:var(--line-2);letter-spacing:-.04em}
.lost h1{margin-top:14px;font-size:30px}
.lost p{margin-top:14px;color:var(--muted)}
.lost .ask{margin:24px 0}

/* ---------- 窄屏 ---------- */
@media (max-width:1040px){
  .hero .wrap{grid-template-columns:1fr;grid-template-areas:"copy" "ticket" "find";row-gap:26px}
  .hero-find{margin-top:0}
  .stats{grid-template-columns:repeat(2,minmax(0,1fr))}
  .stats li{border-left:0;padding:22px 20px}
  .stats li:nth-child(odd){padding-left:0}
  .stats li:nth-child(n+3){border-top:1px solid rgba(255,255,255,.1)}
  .road{grid-template-columns:repeat(2,minmax(0,1fr))}
  .stage{grid-template-columns:1fr;gap:18px;padding-top:32px}
  .stage-side{position:static}
  .qlist{grid-template-columns:1fr}
  .qlist li{border-left:0}
  .qlist li:nth-child(-n+2){border-top:1px solid var(--line)}
  .qlist li:first-child{border-top:0}
  .tool{grid-template-columns:1fr}
  .result{position:static}
  .foot-top{grid-template-columns:1fr 1fr;gap:34px}
  .foot-top > div:first-child{grid-column:1 / -1}
  .ways{grid-template-columns:1fr}
  .compare{grid-template-columns:1fr}
}
@media (max-width:760px){
  .site-head .wrap{min-height:58px;flex-wrap:wrap;gap:0}
  .menu-btn{display:inline-flex}
  .site-nav{display:none;width:100%;flex-direction:column;align-items:stretch;gap:2px;padding-bottom:12px}
  .site-nav.open{display:flex}
  .site-nav a{min-height:48px;font-size:16px;border-radius:var(--r)}
  html{scroll-padding-top:70px}
}
@media (max-width:640px){
  body{font-size:16px}
  .wrap{padding:0 18px}
  .hero{padding:30px 0 34px}
  .hero h1{font-size:31px}
  .hero-lede{margin-top:16px;font-size:16px}
  .tagline{margin-bottom:18px}
  .road{grid-template-columns:1fr;gap:10px}
  .stats b{font-size:32px}
  .ticket-main{padding:20px}
  .ticket-code{flex-wrap:wrap;gap:12px}
  .pick{grid-template-columns:76px minmax(0,1fr);gap:14px;padding:18px 20px}
  .pick-thumb{width:76px;height:40px}
  .sec-head{margin-top:54px}
  .tool-row{grid-template-columns:1fr}
  .doc,.stuck{padding:0 18px}
  .art-head{padding:22px 20px;border-radius:10px}
  .plain{padding:32px 18px 0}
  .art-body{font-size:16.5px}
  .art-body h2{font-size:21px;padding-left:13px}
  .answer p{font-size:16.5px}
  .steps > li{padding:18px 18px 18px 56px}
  .steps > li::before{left:16px}
  .stuck-in{grid-template-columns:1fr;padding:22px}
  .panel,.result{padding:22px}
  .foot-top{grid-template-columns:1fr;gap:28px;padding-top:44px}
  .list-head{padding-top:32px}
  .tool-head{padding-top:30px}
  .meta,.toc-title,.answer-label,.tldr-label,.warn-label,.misread-label,.go-next-label,.calc-label,.related h2,.panel h2,.result h2,.foot-h,.common-label,.list-group h2 .num,.road .num{font-size:13px}
  .src,.shot figcaption,.diagram figcaption,.stuck p,.field .hint,.pick-why,.q-desc,.foot-say,.foot-base{font-size:13.5px}
}
@media (prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}
@media print{.site-head,.site-foot,.stuck,.related{display:none}}
.pick-text{display:block;min-width:0}
.eyebrow a.topic{letter-spacing:.01em}

/* 首页：纸面目录与墨色邀请卡，2026-09-19 */
.home .hero{background:#f7f6f2;padding:52px 0 42px}
.home .hero .wrap{grid-template-columns:minmax(0,1.25fr) minmax(0,1fr);column-gap:64px}
.home .tagline{padding:0 0 10px;border:0;border-bottom:1px solid #cbcbd1;border-radius:0;background:transparent;letter-spacing:.07em;font-weight:500;margin-bottom:24px}
.home .tagline::before{display:none}
.home .hero h1{font-family:"Songti SC","Noto Serif CJK SC","SimSun",serif;font-size:clamp(34px,4.2vw,54px);font-weight:700;line-height:1.32;letter-spacing:-.04em}
.home .mk-1{color:var(--accent);box-shadow:none}
.home .hero-lede{max-width:30em;margin-top:22px;font-size:16px;line-height:1.9;color:#555c68}
.home .hero-find{margin-top:30px}
.home .ask{border:1px solid #b7becb;border-radius:4px}
.home .common{margin-top:17px}
.home .common-label{display:none}
.home .common ul{gap:2px 16px}
.home .common a{padding:3px 0;min-height:40px;background:transparent;border:0;border-radius:0;font-size:13px;text-decoration:underline;text-decoration-color:#c8cbd2;text-underline-offset:5px}
.home .ticket{border:1px solid #17243a;border-radius:8px;background:#17243a;color:#fff;box-shadow:0 15px 28px -22px #17243a55}
.home .ticket-main{padding:24px 26px 20px}
.home .ticket-label{padding:0 0 22px;background:transparent;color:#c2cad9;font-size:13px;letter-spacing:.02em}
.home .ticket-label span{padding:1px 6px;border:1px solid #738099;border-radius:3px;font-size:11px}
.home .ticket-code .num{font-size:44px;letter-spacing:.025em}
.home .copy-btn{border:1px solid #8392b0;background:transparent;min-height:44px;padding:0 13px;font-size:13px;border-radius:4px}
.home .copy-btn:hover{background:#293c5e}
.home .copy-state{font-size:12px;line-height:1.65;min-height:20px;color:#c8e4d9;margin-top:9px}
.invite-link{display:flex;align-items:center;justify-content:space-between;gap:12px;min-height:50px;padding:10px 15px;border:1px solid #fff;border-radius:4px;background:#fff;color:#17243a;text-decoration:none;font-size:15px;font-weight:700;margin-top:12px}
.invite-link span{font-size:12px;font-weight:400}
.invite-link:hover{background:#e6ebff;border-color:#e6ebff}
.home .ticket-gain{margin-top:13px;padding:0;background:transparent;color:#d8dfeb;font-size:13px;line-height:1.8}
.home .ticket-fine{margin-top:11px;color:#afbdd2;font-size:12px;line-height:1.75}
.home .ticket-fine a{color:#dce5f4}
.home .pick{display:block;padding:17px 26px 20px;border-top:1px solid #3b4860;background:transparent}
.home .pick:hover{background:#20314c}
.home .pick-label{color:#b9c8f7;font-size:11px;font-weight:400}
.home .pick-title{font-size:15px;margin-top:4px;font-weight:600;color:#fff}
.home .pick-title::after{color:#b9c8f7}
.home .pick-why{font-size:12px;line-height:1.7;color:#bbc7da;margin-top:6px}
.home .stats-sec{background:#f7f6f2;border-bottom:1px solid #dcdde0;color:var(--ink)}
.home .stats li{display:flex;align-items:center;gap:12px;padding:19px 20px;border-color:#dcdde0}
.home .stats li:first-child{padding-left:0}
.home .stats b{font-size:26px;font-weight:500;color:var(--accent)}
.home .stats span{margin:0;font-size:12px;color:var(--muted)}
.home .road-sec{padding-top:34px}
.home .road{gap:20px}
.home .road a{border:0;border-top:2px solid var(--st);border-radius:0;background:transparent;padding:14px 0 12px}
.home .road a:hover{background:var(--st-soft)}
.home .road .num::before{display:none}
.home .road .num{font-size:13px}
.home .road b{font-size:17px}
.home .road span{font-size:12px}
.home .sec-head{margin-top:54px}
.home .stage{gap:42px;grid-template-columns:220px minmax(0,1fr)}
.home .stage-no{width:auto;height:auto;background:transparent;color:var(--st);font-size:32px;font-weight:400;line-height:1.2}
.home .stage-side h3{margin-top:9px}
.home .qlist{border:0;border-radius:0;column-gap:24px}
.home .qlist li{border-left:0;border-top:1px solid var(--line)}
.home .qlist li:nth-child(-n+2){border-top:1px solid var(--line)}
.home .qlist a{grid-template-columns:22px minmax(0,1fr);column-gap:10px;padding:20px 0 22px}
.home .q-title{font-size:16px;line-height:1.7}
.home .q-desc{font-size:13px;line-height:1.85;margin-top:6px}
/* 复制成功状态不继承文章步骤的 .done 提示框。 */
.copy-btn.done{display:inline-flex;align-items:center;margin-top:0;padding:0 18px;border-left:0;background:var(--c4);color:#fff}
.copy-btn.done::before{content:none}
.home .copy-btn.done{padding:0 13px;border:1px solid #9fbdaa;background:#225540}
.doc:has(.eyebrow a[href$="after.html"]) .art-head{border-left-color:var(--c5);background:linear-gradient(180deg,var(--c5-soft),var(--tint) 70%)}
.eyebrow a[href$="after.html"]::before{background:var(--c5)}
@media(max-width:1040px){
 .home .hero .wrap{grid-template-columns:1fr;row-gap:24px}
 .home .stage{grid-template-columns:1fr;gap:18px}
 .home .stats li:nth-child(odd){padding-left:0}
}
@media(max-width:640px){
 .home .hero{padding:23px 0 28px}
 .home .hero .wrap{row-gap:20px}
 .home .tagline{font-size:12px;margin-bottom:14px;padding-bottom:8px}
 .home .hero h1{font-size:32px;line-height:1.3;letter-spacing:-.05em}
 .home .hero-lede{margin-top:13px;font-size:14px;line-height:1.85}
 .home .ticket-main{padding:17px 18px 16px}
 .home .ticket-label{padding-bottom:14px;font-size:12px}
 .home .ticket-code{flex-wrap:nowrap;gap:10px}
 .home .ticket-code .num{font-size:36px}
 .home .copy-btn{font-size:12px;padding:0 10px;min-height:44px}
 .home .copy-state{min-height:0;margin-top:0}
 .home .copy-state:not(:empty){margin-top:8px}
 .home .ticket-fine{font-size:12px}
 .home .pick{padding:13px 18px 16px}
 .home .pick-why{font-size:12px}
 .home .hero-find{margin-top:0}
 .home .common a{font-size:13px;min-height:44px}
 .home .stats li{padding:14px 10px;gap:8px}
 .home .stats b{font-size:24px}
 .home .stats span{font-size:11px}
 .home .road{grid-template-columns:repeat(2,minmax(0,1fr));gap:12px 20px}
 .home .road a{padding-top:10px}
 .home .road li:last-child{grid-column:1 / -1}
 .home .road li:last-child a{display:grid;grid-template-columns:22px 80px 1fr;align-items:baseline;gap:10px}
 .home .road b{font-size:16px}
 .home .sec-head{margin-top:38px}
 .home .stage{padding-top:25px}
 .home .stage-side{display:grid;grid-template-columns:40px 1fr;column-gap:12px}
 .home .stage-no{grid-row:1 / 3;font-size:28px}
 .home .stage-side h3{margin:0;font-size:23px}
 .home .stage-side p{grid-column:2;font-size:13px}
 .home .stage-more{grid-column:2;margin-top:0}
 .home .qlist a{padding:17px 0}
 .home .q-desc{font-size:13px}
}


/* Long articles: one native contents link stays within the article. */
.article-jump{position:sticky;top:67px;z-index:15;display:flex;align-items:center;justify-content:space-between;gap:16px;width:100%;min-height:44px;margin:18px 0 0;padding:8px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line);background:#fff;color:var(--ink);font-size:14px;font-weight:600;text-decoration:none}
.article-jump span{color:var(--muted);font-size:12px;font-weight:400}
.article-jump:hover{border-color:var(--accent);color:var(--accent)}
#article-toc{scroll-margin-top:42px}
.toc a{display:block;min-height:44px;padding:8px 0;line-height:1.65}
#article-toc:focus-visible{outline:2px solid var(--accent);outline-offset:4px}
@media(max-width:760px){.article-jump{top:59px}body:has(#site-nav.open) .article-jump{visibility:hidden}}
@media print{.article-jump{display:none}}