/* ============================================================
   天下之物，无不用数 —— 秦汉算术活化数据库
   全站共享样式
   ============================================================ */
:root{
  --paper:#f4eddc;
  --paper-2:#ece0c6;
  --card:#fbf6ea;
  --ink:#2a1f14;
  --ink-2:#5a4630;
  --ink-3:#8a7358;
  --dark:#2b1a10;
  --darker:#20130a;
  --red:#a13c28;
  --red-2:#c05a3a;
  --gold:#b8892c;
  --gold-2:#d9b25e;
  --line:#d8c9a8;
  --shadow:0 10px 30px rgba(43,26,16,.12);
  --serif:"Noto Serif SC","Source Han Serif SC","Songti SC","SimSun",serif;
  --kai:"Kaiti SC","KaiTi","STKaiti",var(--serif);
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  font-family:var(--serif);
  background:var(--paper);
  color:var(--ink);
  line-height:1.9;
  letter-spacing:.02em;
  overflow-x:hidden;
  /* 宣纸质感：程序化纸纹（feTurbulence data URI，零外部依赖）+ 点阵 + 顶部柔光 */
  background-image:
    url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="220" height="220"><filter id="n"><feTurbulence type="fractalNoise" baseFrequency="0.85" numOctaves="2"/><feColorMatrix values="0 0 0 0 0.42 0 0 0 0 0.35 0 0 0 0 0.24 0 0 0 0.055 0"/></filter><rect width="220" height="220" filter="url(%23n)"/></svg>'),
    radial-gradient(rgba(138,115,88,.10) 1px, transparent 1.6px),
    linear-gradient(180deg, rgba(255,255,255,.35), rgba(255,255,255,0) 300px);
  background-size:220px 220px, 26px 26px, 100% 100%;
}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
::selection{background:var(--red);color:#fff}

/* ---------- 进入页面的墨色帘幕 ---------- */
#ink-curtain{
  position:fixed;inset:0;z-index:9999;background:var(--darker);
  display:flex;align-items:center;justify-content:center;
  transition:opacity .8s ease,visibility .8s;
}
#ink-curtain.lift{opacity:0;visibility:hidden}
#ink-curtain .seal{
  width:74px;height:74px;border:2px solid var(--gold);color:var(--gold);
  display:flex;align-items:center;justify-content:center;
  font-family:var(--kai);font-size:2rem;
  animation:sealPulse 1.2s ease infinite alternate;
}
@keyframes sealPulse{from{box-shadow:0 0 0 0 rgba(184,137,44,.0);transform:scale(.96)}to{box-shadow:0 0 30px 2px rgba(184,137,44,.35);transform:scale(1)}}

/* ---------- L7 顶部滚动进度筹线（由 site.js 自动注入 #rodProgress） ---------- */
#rodProgress{
  position:fixed;top:0;left:0;height:7px;width:0;
  /* 图纸为 z-index:99；本站导航条 fixed z-index:900，故提到 950 才可见（低于墨幕 9999） */
  z-index:950;pointer-events:none;
  background:repeating-linear-gradient(90deg,#8d3f22 0 26px,#6e2f18 26px 30px,transparent 30px 36px);
  border-radius:0 4px 4px 0;box-shadow:0 1px 4px rgba(42,31,20,.35);
  transition:width .1s linear;
}

/* ---------- 导航 ---------- */
.nav{
  position:fixed;top:0;left:0;right:0;z-index:900;
  display:flex;align-items:center;gap:1.2rem;
  padding:.65rem 4vw;
  background:rgba(32,19,10,.92);
  backdrop-filter:blur(8px);
  color:#e9dfc8;
  border-bottom:1px solid rgba(184,137,44,.35);
  transform:translateY(-100%);
  animation:navDrop .7s .3s ease forwards;
}
@keyframes navDrop{to{transform:translateY(0)}}
.nav .brand{
  font-family:var(--kai);font-size:1.06rem;letter-spacing:.12em;color:var(--gold-2);
  white-space:nowrap;display:flex;align-items:center;gap:.55rem;
}
.nav .brand .mini-seal{
  width:26px;height:26px;border:1px solid var(--gold);display:inline-flex;
  align-items:center;justify-content:center;font-size:.85rem;color:var(--gold-2);
}
.nav .links{display:flex;gap:.2rem;margin-left:auto;flex-wrap:wrap}
.nav .links a{
  padding:.35rem .8rem;font-size:.92rem;letter-spacing:.14em;
  position:relative;opacity:.82;transition:.25s;white-space:nowrap;
}
.nav .links a::after{
  content:"";position:absolute;left:.8rem;right:.8rem;bottom:.15rem;height:2px;
  background:linear-gradient(90deg,var(--red-2),var(--gold));
  transform:scaleX(0);transform-origin:left;transition:transform .3s;
}
.nav .links a:hover{opacity:1}
.nav .links a:hover::after,.nav .links a.on::after{transform:scaleX(1)}
.nav .links a.on{opacity:1;color:var(--gold-2)}

/* ---------- 通用版式 ---------- */
.wrap{max-width:1120px;margin:0 auto;padding:0 4vw}
section.block{padding:5.2rem 0 2.5rem}
.sec-head{display:flex;align-items:flex-start;gap:1.1rem;margin-bottom:2.2rem}
.sec-head .num{
  font-family:var(--kai);font-size:2.6rem;color:var(--gold);line-height:1;
  border-top:2px solid var(--gold);padding-top:.4rem;min-width:2.8rem;text-align:center;
}
.sec-head .kicker{font-size:.85rem;letter-spacing:.5em;color:var(--red);margin-bottom:.35rem}
.sec-head h2{font-size:2rem;letter-spacing:.08em;line-height:1.35}
.sec-head .sub{color:var(--ink-2);margin-top:.5rem;max-width:46em}
.center{text-align:center}

/* ---------- 卡片 ---------- */
.card{
  background:var(--card);border:1px solid var(--line);
  box-shadow:var(--shadow);padding:1.6rem 1.7rem;position:relative;
  transition:transform .35s ease, box-shadow .35s ease;
}
.card:hover{transform:translateY(-5px);box-shadow:0 18px 40px rgba(43,26,16,.18)}
.card h3{font-size:1.15rem;margin-bottom:.5rem;letter-spacing:.05em}
.card .tag{
  display:inline-block;font-size:.74rem;letter-spacing:.18em;color:#fff;
  background:var(--red);padding:.1rem .55rem;margin-bottom:.6rem;
}
.card p{font-size:.95rem;color:var(--ink-2)}
.grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:1.4rem}
.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:1.4rem}
@media(max-width:860px){.grid-2,.grid-3{grid-template-columns:1fr}}

/* 深色引文卡（仿参考站） */
.quote-card{
  background:linear-gradient(120deg,var(--darker),#33200f 70%,#2b1a10);
  color:#efe6d2;padding:3rem 3.2rem;position:relative;overflow:hidden;
  box-shadow:0 20px 50px rgba(32,19,10,.35);
}
.quote-card .src{color:var(--gold-2);letter-spacing:.4em;font-size:.9rem;margin-bottom:1.2rem}
.quote-card blockquote{
  font-family:var(--kai);font-size:clamp(1.5rem,3.2vw,2.3rem);line-height:1.8;letter-spacing:.1em;
}
.quote-card .bg-char{
  position:absolute;right:2%;top:50%;transform:translateY(-50%);
  font-family:var(--kai);font-size:16rem;color:rgba(233,223,200,.05);pointer-events:none;
  user-select:none;line-height:1;
}
.quote-card .chips{display:flex;gap:.7rem;margin-top:1.6rem;flex-wrap:wrap}
.quote-card .chips span{
  border:1px solid rgba(233,223,200,.35);padding:.25rem .8rem;font-size:.82rem;letter-spacing:.12em;
}

/* ---------- ③ 漆器斜光：深色卡缓慢扫过的斜向高光 ----------
   宿主需 position:relative + overflow:hidden（下方已为四个内置深色卡补齐）；
   新写的深色卡加 .sheen-host 即可获得同款效果。
   实现用 ::before（.quote-card 的 .bg-char 是真实元素而非伪元素，二者不冲突）。 */
.quote-card,.converter,.scan-band,.jj-detail,.sheen-host{position:relative;overflow:hidden}
.quote-card::before,
.converter::before,
.scan-band::before,
.jj-detail::before,
.sheen-host::before{
  content:"";position:absolute;top:-60%;bottom:-60%;width:34%;left:-45%;
  z-index:1;pointer-events:none;
  background:linear-gradient(100deg,transparent,rgba(233,214,164,.09) 45%,rgba(233,214,164,.16) 50%,rgba(233,214,164,.09) 55%,transparent);
  transform:skewX(-18deg);
  animation:sheen 6.5s ease-in-out infinite;
}
@keyframes sheen{0%,55%,100%{left:-45%}20%,35%{left:115%}}

/* ---------- 滚动进场 ---------- */
.reveal{opacity:0;transform:translateY(34px);transition:opacity .8s ease,transform .8s cubic-bezier(.2,.7,.2,1)}
.reveal.in{opacity:1;transform:none}
.reveal.from-left{transform:translateX(-46px)}
.reveal.from-right{transform:translateX(46px)}
.reveal.from-left.in,.reveal.from-right.in{transform:none}
.reveal.zoom{transform:scale(.92)}
.reveal.zoom.in{transform:scale(1)}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;gap:.5rem;cursor:pointer;
  font-family:var(--serif);font-size:.95rem;letter-spacing:.15em;
  padding:.65rem 1.6rem;border:1px solid var(--ink);background:transparent;color:var(--ink);
  position:relative;overflow:hidden;transition:color .3s;user-select:none;
}
.btn::before{
  content:"";position:absolute;inset:0;background:var(--ink);z-index:-1;
  transform:scaleX(0);transform-origin:left;transition:transform .35s ease;
}
.btn:hover{color:var(--paper)}
.btn:hover::before{transform:scaleX(1)}
.btn.red{border-color:var(--red);color:var(--red)}
.btn.red::before{background:var(--red)}
.btn.red:hover{color:#fff}
.btn.gold-dark{border-color:var(--gold-2);color:var(--gold-2)}
.btn.gold-dark::before{background:var(--gold-2)}
.btn.gold-dark:hover{color:var(--darker)}
.btn:disabled{opacity:.35;pointer-events:none}

/* ---------- 页脚 ---------- */
footer{
  margin-top:5rem;background:var(--darker);color:#cbbfa5;
  padding:3rem 4vw 2.2rem;text-align:center;font-size:.9rem;letter-spacing:.1em;
}
footer .foot-title{font-family:var(--kai);color:var(--gold-2);font-size:1.2rem;margin-bottom:1rem;letter-spacing:.3em}
footer .foot-links{display:flex;justify-content:center;gap:1.6rem;flex-wrap:wrap;margin-bottom:1.4rem}
footer .foot-links a{opacity:.75;transition:.25s}
footer .foot-links a:hover{opacity:1;color:var(--gold-2)}
footer .dim{opacity:.5;font-size:.8rem}

/* ---------- 页面 Hero（子页） ---------- */
.page-hero{
  padding:9.5rem 4vw 4rem;position:relative;overflow:hidden;
  background:
    radial-gradient(1200px 500px at 80% -10%, rgba(184,137,44,.14), transparent 60%),
    linear-gradient(180deg,#efe5cd, var(--paper));
}
.page-hero .kicker{letter-spacing:.6em;color:var(--red);font-size:.9rem;margin-bottom:1rem}
.page-hero h1{
  font-family:var(--kai);font-size:clamp(2.2rem,5.5vw,3.6rem);letter-spacing:.14em;
  margin-bottom:1.1rem;
}
.page-hero .lead{max-width:44em;color:var(--ink-2);font-size:1.02rem}
.page-hero .big-char{
  position:absolute;right:3vw;top:45%;transform:translateY(-50%);
  font-family:var(--kai);font-size:clamp(9rem,22vw,20rem);line-height:1;
  color:rgba(161,60,40,.07);pointer-events:none;user-select:none;
  /* ③ 毛笔显形：遮罩自上而下"写"出主题字，页面加载后播放一次 */
  -webkit-mask-image:linear-gradient(160deg,#000 0 46%,transparent 54% 100%);
          mask-image:linear-gradient(160deg,#000 0 46%,transparent 54% 100%);
  -webkit-mask-size:100% 340%;        mask-size:100% 340%;
  -webkit-mask-position:0 100%;       mask-position:0 100%;
  -webkit-mask-repeat:no-repeat;      mask-repeat:no-repeat;
  animation:brushIn 1.8s .4s cubic-bezier(.5,.1,.3,1) forwards;
}
@keyframes brushIn{to{-webkit-mask-position:0 0;mask-position:0 0}}
.crumbs{position:absolute;top:5.2rem;font-size:.82rem;letter-spacing:.2em;color:var(--ink-3)}
.crumbs a:hover{color:var(--red)}

/* ---------- 算筹 SVG ---------- */
.rod-svg .rod-bar{
  stroke:#5f2a16;stroke-width:.6;
  filter:drop-shadow(0 1.5px 1.5px rgba(43,26,16,.35));
}
.rod-svg .rod-empty{fill:none;stroke:#c9b892;stroke-dasharray:4 4;stroke-width:1}
/* ⑧ 筹的物理：落筹 → 过冲 3px → 回弹归位（0.45s） */
.rod-fall .rod-bar{animation:rodDrop .45s cubic-bezier(.2,.8,.3,1.2) backwards}
@keyframes rodDrop{
  0%{transform:translateY(-26px);opacity:0}
  60%{transform:translateY(3px);opacity:1}
  80%{transform:translateY(-2px)}
  100%{transform:translateY(0);opacity:1}
}
/* 旧名保留为同义别名，避免任何遗留 animation:rodFall 失效 */
@keyframes rodFall{
  0%{transform:translateY(-26px);opacity:0}
  60%{transform:translateY(3px);opacity:1}
  80%{transform:translateY(-2px)}
  100%{transform:translateY(0);opacity:1}
}

/* ---------- L1 鼠标筹迹（Site.attachTrail(el) 注册后生效） ---------- */
.trail-host{position:relative;overflow:hidden}
.trail-rod{
  position:absolute;width:26px;height:5px;border-radius:3px;
  background:linear-gradient(90deg,#a04a28,#6e2f18);
  pointer-events:none;animation:tfall .9s ease-out forwards;
}
@keyframes tfall{from{opacity:.9}to{opacity:0;transform:translateY(46px) rotate(var(--tr,60deg))}}

/* 摆法对照表 */
.rod-table{width:100%;border-collapse:collapse;background:var(--card);box-shadow:var(--shadow)}
.rod-table th{
  background:linear-gradient(180deg,#7c3a20,#5f2a16);color:#f3e9d4;
  font-weight:400;letter-spacing:.3em;padding:.7rem .4rem;font-size:1rem;
}
.rod-table td{border:1px solid var(--line);text-align:center;padding:.8rem .3rem}
.rod-table td.lab{font-size:.95rem;letter-spacing:.1em;color:var(--ink-2);width:7.5em}
.rod-table td.lab b{display:block;font-size:1.05rem;color:var(--ink)}
.table-scroll{overflow-x:auto;-webkit-overflow-scrolling:touch}

/* ---------- 步骤播放器（四则运算演示） ---------- */
.player{background:var(--card);border:1px solid var(--line);box-shadow:var(--shadow)}
.player .p-head{
  display:flex;align-items:center;gap:1rem;flex-wrap:wrap;
  padding:1rem 1.4rem;border-bottom:1px dashed var(--line);
}
.player .p-head h3{font-size:1.1rem;letter-spacing:.06em}
.player .p-head .formula{
  font-family:var(--kai);color:var(--red);font-size:1.15rem;letter-spacing:.08em;
}
.player .p-stage{padding:1.6rem 1.4rem;min-height:200px}
.player .rows{display:grid;gap:.6rem}
.player .rrow{
  display:grid;grid-template-columns:5.5em 1fr;align-items:center;gap:1rem;
  background:rgba(255,255,255,.5);border:1px solid var(--line);padding:.5rem .9rem;
  transition:background .3s, border-color .3s;
}
.player .rrow.hot{background:#fdf3df;border-color:var(--gold)}
.player .rrow .rlab{font-size:.85rem;letter-spacing:.25em;color:var(--ink-2);text-align:center}
.player .rrow .rlab b{display:block;font-size:1rem;color:var(--red);letter-spacing:.1em}
.player .rrow .rval{min-height:44px;display:flex;align-items:center;gap:.6rem;flex-wrap:wrap}
.player .rrow .num-echo{font-size:.85rem;color:var(--ink-3);margin-left:auto;font-variant-numeric:tabular-nums}
.player .p-note{
  margin:0 1.4rem;padding:.9rem 1.1rem;background:#f6ecd7;border-left:3px solid var(--gold);
  font-size:.93rem;color:var(--ink-2);min-height:3.4em;
}
.player .p-ctrl{display:flex;align-items:center;gap:.7rem;padding:1.1rem 1.4rem;flex-wrap:wrap}
.player .p-ctrl .step-ind{margin-left:auto;font-size:.85rem;letter-spacing:.15em;color:var(--ink-3)}
.player .bar{height:3px;background:var(--paper-2);position:relative;overflow:hidden}
.player .bar i{position:absolute;left:0;top:0;bottom:0;background:linear-gradient(90deg,var(--red),var(--gold));transition:width .4s ease}

/* ---------- 转换器 ---------- */
.converter{
  background:linear-gradient(120deg,var(--darker),#33200f);color:#efe6d2;
  padding:2.4rem 2.6rem;box-shadow:0 20px 50px rgba(32,19,10,.35);
}
.converter .c-in{display:flex;gap:1rem;align-items:center;flex-wrap:wrap;margin-bottom:1.4rem}
.converter input[type=number],.converter input[type=text]{
  background:rgba(244,237,220,.08);border:1px solid rgba(217,178,94,.5);color:#f4edd7;
  font-family:var(--serif);font-size:1.4rem;letter-spacing:.2em;padding:.5rem 1rem;width:11em;
  outline:none;transition:.3s;font-variant-numeric:tabular-nums;
}
.converter input:focus{border-color:var(--gold-2);box-shadow:0 0 0 3px rgba(217,178,94,.18)}
.converter .c-stage{
  min-height:120px;background:rgba(244,237,220,.06);border:1px dashed rgba(217,178,94,.35);
  display:flex;align-items:center;justify-content:center;padding:1.4rem;gap:1rem;flex-wrap:wrap;
}
.converter .c-read{margin-top:1rem;font-size:.95rem;color:var(--gold-2);letter-spacing:.1em;min-height:1.8em}
.digit-slot{display:flex;flex-direction:column;align-items:center;gap:.45rem}
.digit-slot .d-cap{font-size:.75rem;letter-spacing:.2em;color:rgba(239,230,210,.55)}
.digit-slot .d-cap.on-paper{color:var(--ink-3)}

/* ---------- 时间线 ---------- */
.timeline{position:relative;padding-left:2.2rem}
.timeline::before{
  content:"";position:absolute;left:.55rem;top:.4rem;bottom:.4rem;width:2px;
  background:linear-gradient(180deg,var(--gold),var(--red) 60%,transparent);
}
.t-item{position:relative;padding:0 0 2.2rem 1.2rem}
.t-item::before{
  content:"";position:absolute;left:-2.05rem;top:.55rem;width:12px;height:12px;
  background:var(--paper);border:3px solid var(--red);border-radius:50%;
  transition:transform .3s, background .3s;
}
.t-item:hover::before{transform:scale(1.35);background:var(--gold-2)}
.t-item .t-era{
  display:inline-block;font-size:.78rem;letter-spacing:.2em;color:#fff;background:var(--ink-2);
  padding:.08rem .6rem;margin-bottom:.4rem;
}
.t-item h3{font-size:1.12rem;margin-bottom:.3rem}
.t-item p{font-size:.94rem;color:var(--ink-2);max-width:52em}

/* ---------- 数字统计 ---------- */
.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:1rem}
.stat{
  text-align:center;padding:1.4rem .6rem;background:var(--card);
  border:1px solid var(--line);box-shadow:var(--shadow);
}
.stat .n{
  font-size:2.4rem;font-family:var(--kai);color:var(--red);line-height:1.1;
  font-variant-numeric:tabular-nums;
}
.stat .n small{font-size:1.1rem;color:var(--gold)}
.stat .l{font-size:.85rem;letter-spacing:.2em;color:var(--ink-2);margin-top:.35rem}

/* ---------- 翻转卡片 ---------- */
.flip{perspective:1100px;height:230px;cursor:pointer}
.flip .inner{
  position:relative;width:100%;height:100%;transition:transform .7s cubic-bezier(.3,.7,.3,1);
  transform-style:preserve-3d;
}
.flip:hover .inner,.flip.flipped .inner{transform:rotateY(180deg)}
.flip .face{
  position:absolute;inset:0;backface-visibility:hidden;display:flex;flex-direction:column;
  align-items:center;justify-content:center;text-align:center;padding:1.2rem;gap:.5rem;
}
.flip .front{background:var(--card);border:1px solid var(--line);box-shadow:var(--shadow)}
.flip .front .f-icon{font-family:var(--kai);font-size:2.2rem;color:var(--red)}
.flip .front h4{font-size:1.05rem}
.flip .front .hint{font-size:.75rem;letter-spacing:.25em;color:var(--ink-3)}
.flip .back{
  background:linear-gradient(135deg,var(--darker),#3a2312);color:#efe6d2;
  transform:rotateY(180deg);box-shadow:0 16px 40px rgba(32,19,10,.35);
}
.flip .back h5{color:var(--gold-2);letter-spacing:.15em;font-size:.95rem;margin-bottom:.2rem}
.flip .back p{font-size:.84rem;line-height:1.75;color:rgba(239,230,210,.9)}

/* ---------- 九九表 ---------- */
.jj-grid{
  display:grid;grid-template-columns:repeat(9,1fr);gap:6px;user-select:none;
}
.jj-cell{
  aspect-ratio:1/1;display:flex;flex-direction:column;align-items:center;justify-content:center;
  background:var(--card);border:1px solid var(--line);cursor:pointer;font-size:.95rem;
  transition:transform .2s, background .3s, color .3s, box-shadow .3s;position:relative;
}
.jj-cell .f{font-size:.72rem;color:var(--ink-3);letter-spacing:.03em}
.jj-cell .v{font-family:var(--kai);font-size:1.25rem;color:var(--red)}
.jj-cell:hover{transform:translateY(-3px) scale(1.04);box-shadow:0 8px 18px rgba(43,26,16,.18);z-index:2}
.jj-cell.sel{background:var(--darker);border-color:var(--gold)}
.jj-cell.sel .f{color:var(--gold-2)}
.jj-cell.sel .v{color:#fff}
.jj-cell.dimmed{opacity:.28}
.jj-detail{
  margin-top:1.4rem;background:linear-gradient(120deg,var(--darker),#33200f);
  color:#efe6d2;padding:1.6rem 2rem;display:flex;align-items:center;gap:2rem;flex-wrap:wrap;
  box-shadow:0 16px 40px rgba(32,19,10,.3);min-height:120px;
}
.jj-detail .koujue{font-family:var(--kai);font-size:1.9rem;letter-spacing:.15em;color:var(--gold-2)}
.jj-detail .jj-rod{display:flex;align-items:center;gap:1rem}
.jj-detail .cap{font-size:.8rem;letter-spacing:.3em;color:rgba(239,230,210,.55)}

/* ---------- 清华算表 ---------- */
.qh-wrap{background:var(--card);border:1px solid var(--line);box-shadow:var(--shadow);padding:1.4rem}
.qh-grid{border-collapse:collapse;margin:0 auto;font-variant-numeric:tabular-nums}
.qh-grid td{
  border:1px solid #e2d5b4;min-width:34px;height:30px;text-align:center;font-size:.72rem;
  color:var(--ink-2);transition:background .25s,color .25s,transform .2s;
}
.qh-grid td.hd{background:#efe3c6;color:var(--ink);font-weight:700;font-size:.78rem}
.qh-grid td.hd.hl{background:var(--gold);color:#fff}
.qh-grid td.cross{background:#f7e3b0}
.qh-grid td.hit{background:var(--red);color:#fff;font-weight:700;transform:scale(1.12)}
.qh-ctrl{display:flex;gap:1rem;align-items:flex-end;flex-wrap:wrap;margin-bottom:1.2rem}
.qh-ctrl label{font-size:.85rem;letter-spacing:.15em;color:var(--ink-2);display:block;margin-bottom:.3rem}
.qh-ctrl input{
  font-family:var(--serif);font-size:1.3rem;padding:.4rem .8rem;width:7em;
  border:1px solid var(--line);background:#fff;outline:none;
}
.qh-ctrl input:focus{border-color:var(--gold);box-shadow:0 0 0 3px rgba(184,137,44,.18)}
.qh-result{
  font-family:var(--kai);font-size:1.3rem;color:var(--red);letter-spacing:.06em;min-height:2em;
  margin-top:1rem;text-align:center;
}
.qh-result .sum-chip{
  display:inline-block;background:#f7e3b0;border:1px solid var(--gold);color:var(--ink);
  font-family:var(--serif);font-size:.9rem;padding:.05rem .55rem;margin:0 .25rem;
}

/* ---------- 例题版式 ---------- */
.prob{background:var(--card);border:1px solid var(--line);box-shadow:var(--shadow);overflow:hidden}
.prob .p-src{
  background:linear-gradient(90deg,var(--darker),#3a2312);color:var(--gold-2);
  padding:.55rem 1.4rem;font-size:.85rem;letter-spacing:.3em;display:flex;justify-content:space-between;align-items:center
}
.prob .p-src .diff{color:rgba(239,230,210,.6);letter-spacing:.1em}
.prob .p-body{padding:1.5rem 1.7rem}
.prob .p-body .orig{
  font-family:var(--kai);font-size:1.12rem;line-height:2;color:var(--ink);
  border-left:3px solid var(--red);padding:.2rem 0 .2rem 1rem;margin-bottom:1rem;background:#f8f1e0;
}
.prob .p-body .trans{font-size:.92rem;color:var(--ink-2);margin-bottom:1.2rem}
.prob .solve{border-top:1px dashed var(--line);padding-top:1.2rem}
.sol-steps{display:grid;gap:.5rem;margin:.8rem 0}
.sol-step{
  display:flex;gap:.9rem;align-items:baseline;background:rgba(255,255,255,.55);
  border:1px solid var(--line);padding:.55rem .9rem;font-size:.93rem;
  opacity:.35;transform:translateX(-8px);transition:.45s;
}
.sol-step.lit{opacity:1;transform:none;border-color:var(--gold);background:#fdf3df}
.sol-step .s-no{
  font-family:var(--kai);color:var(--red);white-space:nowrap;font-size:1rem;
}
.sol-step .s-math{color:var(--ink);font-variant-numeric:tabular-nums}
.answer-seal{
  display:inline-flex;flex-direction:column;align-items:center;justify-content:center;
  min-width:86px;min-height:86px;border:3px solid var(--red);color:var(--red);
  font-family:var(--kai);font-size:1.25rem;letter-spacing:.05em;padding:.5rem .9rem;
  transform:rotate(-4deg);opacity:0;transition:.5s .2s;line-height:1.5;
  /* ③ 印泥质感：#inkRough 由 site.js 全局注入 0×0 SVG defs，各页面无需内联 */
  filter:url(#inkRough);
}
.answer-seal.stamp{opacity:1;animation:stamp .45s .2s cubic-bezier(.2,2,.4,1) backwards}
@keyframes stamp{from{transform:rotate(-4deg) scale(2);opacity:0}to{transform:rotate(-4deg) scale(1);opacity:1}}

/* ---------- 鸡兔动画 ---------- */
.pen{
  display:flex;flex-wrap:wrap;gap:.45rem;padding:1rem;background:#f2e8cf;
  border:1px solid var(--line);min-height:96px;align-content:flex-start;
}
.pen .animal{
  font-size:1.5rem;line-height:1;transition:transform .4s, filter .4s;
  animation:hop 2.4s ease-in-out infinite;
}
.pen .animal:nth-child(2n){animation-delay:.4s}
.pen .animal:nth-child(3n){animation-delay:.9s}
@keyframes hop{0%,100%{transform:translateY(0)}50%{transform:translateY(-5px)}}
.range-line{display:flex;align-items:center;gap:1rem;margin:.8rem 0;flex-wrap:wrap}
.range-line label{font-size:.9rem;letter-spacing:.1em;color:var(--ink-2);white-space:nowrap}
.range-line input[type=range]{flex:1;min-width:160px;accent-color:var(--red)}
.range-line output{font-family:var(--kai);color:var(--red);font-size:1.15rem;min-width:3em;text-align:center}

/* ---------- 百鸡扫描 ---------- */
.scan-band{
  background:var(--darker);color:#efe6d2;padding:1.6rem 1.8rem;box-shadow:0 16px 40px rgba(32,19,10,.3);
}
.scan-band .scan-row{display:flex;align-items:center;gap:1rem;font-variant-numeric:tabular-nums;flex-wrap:wrap}
.scan-band .scan-now{font-family:var(--kai);font-size:1.25rem;color:var(--gold-2);min-width:11em}
.scan-band .found{display:flex;gap:.8rem;flex-wrap:wrap;margin-top:1.1rem}
.scan-band .sol-chip{
  border:1px solid var(--gold);padding:.5rem .9rem;font-size:.88rem;letter-spacing:.05em;
  background:rgba(217,178,94,.08);animation:chipIn .5s cubic-bezier(.2,1.4,.4,1) backwards;
}
@keyframes chipIn{from{transform:scale(.6);opacity:0}to{transform:scale(1);opacity:1}}

/* ---------- 对比时间线（古今之桥） ---------- */
.vs-row{
  display:grid;grid-template-columns:1fr 120px 1fr;gap:1rem;align-items:stretch;margin-bottom:1.1rem;
}
.vs-cell{padding:1.1rem 1.3rem;border:1px solid var(--line);background:var(--card);box-shadow:var(--shadow)}
.vs-cell h4{font-size:1rem;margin-bottom:.25rem}
.vs-cell .when{font-size:.8rem;letter-spacing:.12em;color:#fff;display:inline-block;padding:.05rem .5rem;margin-bottom:.4rem}
.vs-cell.cn .when{background:var(--red)}
.vs-cell.we .when{background:var(--ink-3)}
.vs-cell p{font-size:.87rem;color:var(--ink-2)}
.vs-mid{
  display:flex;flex-direction:column;align-items:center;justify-content:center;gap:.2rem;
  font-family:var(--kai);color:var(--red);
}
.vs-mid .lead-n{font-size:1.7rem;font-variant-numeric:tabular-nums}
.vs-mid .lead-l{font-size:.78rem;letter-spacing:.25em;color:var(--ink-3)}
@media(max-width:760px){.vs-row{grid-template-columns:1fr}.vs-mid{flex-direction:row}}

/* ---------- 图片卡 ---------- */
.figure{background:var(--card);border:1px solid var(--line);box-shadow:var(--shadow);overflow:hidden}
.figure .ph{overflow:hidden;position:relative}
.figure .ph img{width:100%;height:220px;object-fit:cover;transition:transform .8s ease;filter:sepia(.12)}
.figure:hover .ph img{transform:scale(1.07)}
.figure figcaption{padding:.8rem 1.1rem;font-size:.85rem;color:var(--ink-2);letter-spacing:.05em}
.figure figcaption b{display:block;color:var(--ink);font-size:.95rem;margin-bottom:.15rem}

/* ---------- 占位（内容筹备中） ---------- */
.placeholder{
  border:2px dashed var(--line);padding:3rem;text-align:center;color:var(--ink-3);
  letter-spacing:.3em;font-size:.95rem;background:rgba(255,255,255,.35);
}

/* ---------- 传承链 ---------- */
.chain{display:flex;align-items:stretch;gap:0;flex-wrap:wrap;justify-content:center}
.chain .link-node{
  flex:1;min-width:190px;max-width:250px;background:var(--card);border:1px solid var(--line);
  box-shadow:var(--shadow);padding:1.4rem 1.2rem;text-align:center;position:relative;margin:0 1.4rem 1.4rem;
  transition:transform .3s;
}
.chain .link-node:hover{transform:translateY(-6px)}
.chain .link-node .era{font-size:.75rem;letter-spacing:.25em;color:#fff;background:var(--ink-2);display:inline-block;padding:.06rem .5rem;margin-bottom:.5rem}
.chain .link-node h4{font-family:var(--kai);font-size:1.3rem;color:var(--red);margin-bottom:.4rem}
.chain .link-node p{font-size:.83rem;color:var(--ink-2)}
.chain .link-node:not(:last-child)::after{
  content:"→";position:absolute;right:-2.2rem;top:50%;transform:translateY(-50%);
  font-size:1.6rem;color:var(--gold);
}
@media(max-width:700px){.chain .link-node:not(:last-child)::after{content:"↓";right:50%;top:auto;bottom:-2.1rem;transform:translateX(50%)}}

/* ---------- 杂项 ---------- */
.note-strip{
  display:flex;gap:.9rem;align-items:flex-start;background:#f6ecd7;border-left:3px solid var(--gold);
  padding:1rem 1.3rem;font-size:.92rem;color:var(--ink-2);
}
.note-strip .ic{font-family:var(--kai);color:var(--red);font-size:1.1rem;white-space:nowrap}
.hr-orn{display:flex;align-items:center;gap:1rem;margin:3rem 0;color:var(--gold)}
.hr-orn::before,.hr-orn::after{content:"";flex:1;height:1px;background:linear-gradient(90deg,transparent,var(--gold),transparent)}
.hr-orn span{font-family:var(--kai);letter-spacing:.5em;font-size:.9rem}
.kbd-hint{font-size:.78rem;color:var(--ink-3);letter-spacing:.1em}

/* ============================================================
   护栏：prefers-reduced-motion 降级
   —— 逐条禁用动效并直接落到"终态"，绝不把元素留在起始的隐藏/位移状态
   ============================================================ */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}

  /* —— 本次新增的动效，直接禁用 —— */
  .quote-card::before,.converter::before,.scan-band::before,
  .jj-detail::before,.sheen-host::before{display:none}          /* sheen 漆器斜光 */
  .page-hero .big-char{                                          /* brushIn 毛笔显形 */
    animation:none;
    -webkit-mask-image:none;mask-image:none;
  }
  .rod-fall .rod-bar{animation:none}                             /* rodDrop 落筹回弹 */
  .trail-rod{display:none;animation:none}                        /* trail 鼠标筹迹 */
  #rodProgress{transition:none}

  /* —— 既有动效：停动画，但保证终态可见 —— */
  #ink-curtain,#ink-curtain .seal{transition:none;animation:none}
  .nav{animation:none;transform:none}
  .reveal{transition:none}
  .reveal:not(.in){opacity:1;transform:none}
  .card:hover,.chain .link-node:hover,.jj-cell:hover,.t-item:hover::before{transform:none}
  .flip .inner{transition:none}
  .figure .ph img{transition:none}
  .figure:hover .ph img{transform:none}
  .sol-step{transition:none}
  .answer-seal,.answer-seal.stamp{transition:none;animation:none}
  .pen .animal{animation:none}
  .scan-band .sol-chip{animation:none}
  .player .bar i,.player .rrow{transition:none}
  .btn,.btn::before{transition:none}

  /* —— 页内专属动效的终态兜底（首页 Hero / 认识算筹 / 筹算之术） —— */
  .hero-title .ch,.hero-sub,.hero-cta,.hero-rodline{
    opacity:1!important;transform:none!important;animation:none!important;
  }
  .scroll-hint{animation:none}
  .rod-bundle i{animation:none;transition:none}
  .rod-bundle i:hover{transform:none}
  .op-panel.show{animation:none}
  .chap .veil,.chap{transition:none}
}