/* 書院風格：羊皮紙底、牛津藍、勃艮第紅、古金；襯線字體；所有尺寸以 rem 計，可整體放大縮小 */
:root{
  --bg:#f4eee1; --paper:#fbf8f1; --sf:#fffdf8; --mu:#efe7d6; --bd:#d6c7a8; --rule:#b9a27a;
  --fg:#1d2638; --sub:#5a5546; --br:#0f2c4f; --brf:#fbf6ea; --acc:#7b1e2b; --gold:#a8833f; --crest:#0f2c4f;
  --ok:#2e6a3a; --warn:#8a5a00; --bad:#9b1c22; --hl:#f3e2b0;
  --serif:"EB Garamond","Noto Serif TC","Songti TC","PMingLiU","Times New Roman",serif;
  --display:"Cormorant Garamond","EB Garamond","Noto Serif TC","Songti TC",serif;
  color-scheme:light
}
@media (prefers-color-scheme:dark){:root:not(.light){--bg:#0e1524;--paper:#121b2e;--sf:#17223a;--mu:#22304d;--bd:#3a4867;--rule:#8c7448;--fg:#efe7d4;--sub:#c2b79f;--br:#d4b26b;--brf:#0e1524;--acc:#e3a0a6;--gold:#d4b26b;--crest:#0f2c4f;--ok:#7fc58a;--warn:#e7b85c;--bad:#f0898d;--hl:#3c3220;color-scheme:dark}}
:root.dark{--bg:#0e1524;--paper:#121b2e;--sf:#17223a;--mu:#22304d;--bd:#3a4867;--rule:#8c7448;--fg:#efe7d4;--sub:#c2b79f;--br:#d4b26b;--brf:#0e1524;--acc:#e3a0a6;--gold:#d4b26b;--crest:#0f2c4f;--ok:#7fc58a;--warn:#e7b85c;--bad:#f0898d;--hl:#3c3220;color-scheme:dark}

*{box-sizing:border-box}
html{font-size:18px}
html,body{margin:0;background:var(--bg);color:var(--fg);font-family:var(--serif);line-height:1.7;overflow-x:hidden;-webkit-font-smoothing:antialiased}
body{background-image:radial-gradient(circle at 20% 0%,color-mix(in srgb,var(--paper) 70%,transparent),transparent 60%)}
a{color:var(--acc);text-underline-offset:.2em}
:focus-visible{outline:.15rem solid var(--gold);outline-offset:.15rem}
.skip{position:absolute;left:-999px}.skip:focus{left:.5rem;top:.5rem;z-index:9;background:var(--br);color:var(--brf);padding:.4rem .7rem;border-radius:.3rem}

/* 頂部：牛津藍橫帶＋金色細線 */
.top{position:sticky;top:0;z-index:5;display:flex;align-items:center;gap:.8rem;padding:.45rem 1rem;background:#0f2c4f;color:#f4ecd8;border-bottom:.2rem solid var(--gold);box-shadow:0 .1rem 0 #0a1f38}
.logo{display:flex;align-items:center;gap:.55rem;text-decoration:none;color:#f4ecd8;min-height:2.6rem;white-space:nowrap}
.crest{width:2rem;height:2.4rem;--crest:#0f2c4f;--gold:#d4b26b}
.brand{display:flex;flex-direction:column;line-height:1.1}.brand b{font-family:var(--display);font-size:1.15rem;letter-spacing:.06em}
.brand small{font-family:var(--display);font-variant:small-caps;letter-spacing:.14em;font-size:.68rem;color:#d4b26b}
#nav{display:flex;gap:.1rem;overflow-x:auto;flex:1;scrollbar-width:none}
#nav a{padding:.55rem .7rem;text-decoration:none;color:#e6dcc4;white-space:nowrap;border-bottom:.12rem solid transparent;font-size:.95rem}
#nav a:hover{color:#fff}#nav a.on{color:#fff;border-bottom-color:#d4b26b}
.tools{display:flex;gap:.25rem;align-items:center}
.tool{min-width:2.45rem;min-height:2.45rem;border:1px solid #6d7f9c;background:transparent;color:#f4ecd8;border-radius:.3rem;font:600 .95rem var(--serif);cursor:pointer}
.tool:hover{border-color:#d4b26b;color:#fff}.tool:disabled{opacity:.4;cursor:not-allowed}.tool.val{font-size:.75rem;min-width:3.2rem}
@media(max-width:760px){.brand{display:none}.tool.val{display:none}}

main{max-width:72rem;margin:0 auto;padding:1.6rem 1rem 3rem;outline:none}
footer{text-align:center;color:var(--sub);font-size:.78rem;padding:1rem;border-top:1px solid var(--bd);font-style:italic}
.orn{color:var(--gold);font-style:normal}

h1{font-family:var(--display);font-weight:700;font-size:2rem;margin:.2rem 0 .9rem;letter-spacing:.02em;color:var(--br)}
:root.dark h1{color:var(--fg)}
h1::after{content:"";display:block;width:4rem;height:2px;margin-top:.35rem;background:linear-gradient(90deg,var(--gold),transparent)}
h2{font-family:var(--display);font-size:1.3rem;font-weight:700;margin:0 0 .5rem;color:var(--fg)}
.sub{color:var(--sub)}

/* 卡片：象牙紙＋雙線框 */
.card{background:var(--sf);border:1px solid var(--bd);border-radius:.4rem;padding:1.1rem 1.2rem;margin-bottom:.9rem;box-shadow:0 1px 0 var(--bd),inset 0 0 0 3px var(--sf),inset 0 0 0 4px color-mix(in srgb,var(--rule) 35%,transparent)}
a.card{transition:transform .15s,box-shadow .15s}a.card:hover{transform:translateY(-2px);box-shadow:0 .4rem 1rem #00000014,inset 0 0 0 3px var(--sf),inset 0 0 0 4px var(--gold)}
a.card h2{color:var(--br)}:root.dark a.card h2{color:var(--gold)}
.grid{display:grid;gap:.9rem;grid-template-columns:repeat(auto-fill,minmax(15rem,1fr))}
.two{display:grid;gap:.9rem;grid-template-columns:1fr}@media(min-width:56rem){.two{grid-template-columns:minmax(0,1fr) minmax(18rem,24rem)}}

/* 按鈕 */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:.35rem;min-height:2.6rem;padding:.4rem 1rem;border-radius:.3rem;border:1px solid var(--br);background:var(--br);color:var(--brf);font:600 1rem var(--serif);letter-spacing:.03em;cursor:pointer;text-decoration:none;transition:filter .15s}
.btn:hover{filter:brightness(1.12)}
.btn.ghost{background:transparent;color:var(--fg);border-color:var(--rule)}
.btn.ghost:hover{background:var(--mu);filter:none}
.btn.on,.btn.ghost.on{background:var(--acc);border-color:var(--acc);color:#fff}
:root.dark .btn.on{color:#1a0f12}
.btn:disabled{opacity:.4;cursor:not-allowed;filter:none}
.row{display:flex;flex-wrap:wrap;gap:.5rem;align-items:center}
.chip{display:inline-block;border:1px solid var(--rule);border-radius:2rem;padding:0 .65rem;font-size:.78rem;color:var(--sub);font-variant:small-caps;letter-spacing:.04em;background:var(--paper)}
kbd{border:1px solid currentColor;border-radius:.2rem;padding:0 .25rem;font:.7rem var(--serif);opacity:.85}

/* 選項：蠟封字母 */
.opt{display:flex;gap:.7rem;align-items:flex-start;min-height:2.9rem;border:1px solid var(--bd);border-radius:.35rem;padding:.55rem .7rem;margin:.4rem 0;cursor:pointer;background:var(--paper);transition:border-color .15s,background .15s}
.opt:hover{border-color:var(--rule)}
.opt input{position:absolute;opacity:0}
.opt .l{flex:none;width:1.9rem;height:1.9rem;border-radius:50%;border:1.5px solid var(--rule);display:grid;place-items:center;font:700 1rem var(--display);color:var(--br);background:var(--sf)}
:root.dark .opt .l{color:var(--gold)}
.opt.sel{border-color:var(--acc);background:color-mix(in srgb,var(--acc) 7%,var(--paper))}
.opt.sel .l{background:var(--acc);border-color:var(--acc);color:#fff}
.opt.ok{border-color:var(--ok);background:color-mix(in srgb,var(--ok) 10%,var(--paper))}.opt.ok .l{background:var(--ok);border-color:var(--ok);color:#fff}
.opt.ng{border-color:var(--bad);background:color-mix(in srgb,var(--bad) 9%,var(--paper))}
.opt:focus-within{outline:.15rem solid var(--gold);outline-offset:.1rem}
fieldset legend{font-variant:small-caps;letter-spacing:.08em}
.opts.p{display:grid;grid-template-columns:1fr 1fr;gap:.5rem}

/* 題號導覽 */
.qnav{display:grid;grid-template-columns:repeat(8,1fr);gap:.35rem}
.qnav button{min-height:2.45rem;border-radius:.25rem;border:1px solid var(--bd);background:var(--paper);color:var(--fg);font:600 .9rem var(--serif);cursor:pointer}
.qnav button.ans{background:var(--br);color:var(--brf);border-color:var(--br)}.qnav button.cur{outline:.13rem solid var(--acc);outline-offset:1px}.qnav button:disabled{opacity:.35}

.bar{height:.4rem;background:var(--mu);border-radius:1rem;overflow:hidden}.bar>i{display:block;height:100%;background:linear-gradient(90deg,var(--br),var(--acc))}

/* 逐字稿：講義行距、金色高亮 */
.tr{max-height:22rem;overflow:auto;padding:0 .2rem 0 0;margin:0;counter-reset:ln}
.tr li{list-style:none;counter-increment:ln}
.tr button{display:grid;grid-template-columns:1.8rem 1fr;gap:.3rem;width:100%;text-align:left;border:0;border-left:2px solid transparent;background:none;color:var(--fg);font:1rem/1.65 var(--serif);padding:.3rem .5rem;cursor:pointer}
.tr button::before{content:counter(ln);color:var(--gold);font:italic .8rem var(--display);padding-top:.15rem}
.tr button:hover{background:var(--mu)}
.tr button.act{background:var(--hl);border-left-color:var(--acc)}
.res{padding:.45rem .8rem;border-radius:.3rem;font-weight:600;border-left:.25rem solid}
.res.ok{color:var(--ok);background:color-mix(in srgb,var(--ok) 10%,transparent)}.res.ng{color:var(--bad);background:color-mix(in srgb,var(--bad) 10%,transparent)}.res.half{color:var(--warn)}
.lv{display:inline-grid;place-items:center;min-width:2.2rem;height:2.2rem;border-radius:50%;border:2px solid;font:700 1.2rem var(--display)}.lvA{color:var(--ok)}.lvF{color:var(--bad)}.lvB,.lvC{color:var(--warn)}
table{border-collapse:collapse;width:100%}td,th{padding:.35rem .4rem;border-top:1px solid var(--bd);text-align:left}
caption{font-variant:small-caps;letter-spacing:.06em}
.heat td{text-align:center;border:2px solid var(--sf)}
input[type=number],select,textarea{min-height:2.6rem;border:1px solid var(--rule);border-radius:.3rem;background:var(--paper);color:var(--fg);font:1rem var(--serif);padding:.3rem .6rem}textarea{width:100%}
input[type=range]{flex:1;min-height:2.6rem;accent-color:var(--acc)}
.pic{max-width:100%;max-height:46vh;display:block;margin:.5rem auto;background:#fff;border-radius:.3rem;border:1px solid var(--bd);padding:.3rem}
.optpic{max-height:9rem;max-width:100%;background:#fff;border-radius:.2rem}
.warn{border:1px solid var(--warn);color:var(--warn);border-radius:.3rem;padding:.5rem .8rem}

/* 播放列 */
#pb,#now{background:linear-gradient(var(--sf),var(--paper))}
#pb .chip{font-variant:normal}

/* 投影模式：大字（隨使用者字級縮放） */
.big{font-size:1.55rem}.big .opt{font-size:1.45rem}.big .opt .l{width:2.5rem;height:2.5rem;font-size:1.3rem}
.big .tr button{font-size:1.35rem}

#toast{position:fixed;left:50%;bottom:1rem;transform:translateX(-50%);z-index:9}
#toast div{background:var(--sf);border:1px solid var(--rule);border-left:.25rem solid var(--acc);border-radius:.3rem;padding:.6rem 1rem;margin-top:.4rem;box-shadow:0 .4rem 1.2rem #0003}
@media(prefers-reduced-motion:reduce){*{transition:none!important}}
@media print{.top,footer,#pb,#now,.btn{display:none}body{background:#fff}}

main:focus,main:focus-visible{outline:none}
#theme{font-size:1.05rem}
/* 數字一律用齊線數字，避免古典字體的舊式數字（11 看起來像 ıı） */
html,body,h1,h2,.btn,.chip,.qnav button{font-variant-numeric:lining-nums tabular-nums}
.year{display:inline-block;font:600 .8rem var(--serif);letter-spacing:.06em;color:var(--acc);border-bottom:1px solid var(--gold);margin-bottom:.35rem;padding-bottom:.1rem}
/* 趨勢：放大鏡與題目清單視窗 */
.heat td.hit,.hit td{position:relative}
.lens{position:absolute;right:.25rem;top:50%;transform:translateY(-50%);width:1.9rem;height:1.9rem;display:grid;place-items:center;border-radius:50%;border:1px solid var(--gold);background:var(--sf);color:var(--acc);cursor:zoom-in;opacity:0;transition:opacity .15s;padding:0}
.lens svg{width:1.05rem;height:1.05rem}
.hit:hover .lens,.hit:focus-within .lens,.lens:focus-visible{opacity:1}
@media(hover:none){.lens{opacity:.85}}
.hit td:last-child{padding-right:2.6rem}
dialog#dlg{width:min(46rem,94vw);max-height:84vh;border:1px solid var(--rule);border-radius:.5rem;background:var(--sf);color:var(--fg);padding:0;box-shadow:0 1rem 3rem #0005}
dialog#dlg::backdrop{background:#0f1a2c99}
.dlg-head{display:flex;align-items:center;justify-content:space-between;gap:.5rem;padding:.8rem 1rem;border-bottom:2px solid var(--gold);background:var(--paper);position:sticky;top:0}
.dlg-head h2{margin:0}
.qlist{list-style:none;margin:0;padding:.5rem;overflow:auto;max-height:70vh}
.qitem{display:grid;grid-template-columns:1fr auto;gap:.2rem .6rem;width:100%;text-align:left;background:var(--paper);border:1px solid var(--bd);border-radius:.35rem;padding:.6rem .8rem;margin:.3rem 0;cursor:pointer;color:var(--fg);font:1rem var(--serif)}
.qitem:hover,.qitem:focus-visible{border-color:var(--acc);background:color-mix(in srgb,var(--acc) 6%,var(--paper))}
.qitem .snip{grid-column:1/-1;color:var(--sub);font-style:italic}
/* KC 科基語測 logo：象牙底牌，避免在深藍頂欄上失色 */
.kc{display:inline-flex;align-items:center;background:#fffdf8;border-radius:.35rem;padding:.2rem .45rem;box-shadow:inset 0 0 0 1px #d4b26b}
.kc img{height:1.9rem;width:auto;display:block}
.hero{display:flex;align-items:center;gap:1.2rem;flex-wrap:wrap;margin-bottom:.6rem}
.hero-logo{height:4.2rem;width:auto;background:#fffdf8;border:1px solid var(--rule);border-radius:.4rem;padding:.4rem .7rem}
.hero h1{margin-top:0}
@media(max-width:760px){.kc img{height:1.6rem}.hero-logo{height:3rem}}

/* 試卷卡：書院對開本 folio */
.shelf{display:flex;align-items:center;gap:.8rem;margin:1.4rem 0 .8rem;font:600 1rem var(--display);letter-spacing:.2em;color:var(--acc)}
.shelf::before,.shelf::after{content:"";flex:1;height:1px;background:linear-gradient(90deg,transparent,var(--rule))}
.shelf::after{background:linear-gradient(90deg,var(--rule),transparent)}
.folios{grid-template-columns:repeat(auto-fill,minmax(16.5rem,1fr));gap:1.2rem}
.folio{display:flex;flex-direction:column;background:var(--sf);border:1px solid var(--bd);border-radius:.25rem;overflow:hidden;box-shadow:0 .1rem .2rem rgba(15,44,79,.06),0 .6rem 1.4rem -.8rem rgba(15,44,79,.35);transition:transform .2s,box-shadow .2s}
.folio:hover{transform:translateY(-.15rem);box-shadow:0 .1rem .2rem rgba(15,44,79,.08),0 1rem 2rem -1rem rgba(15,44,79,.45)}
.fh{position:relative;display:flex;align-items:flex-end;gap:.8rem;padding:1rem 1.2rem .8rem;background:#0f2c4f;color:#f4ecd8;border-bottom:.2rem solid #d4b26b;
  background-image:repeating-linear-gradient(135deg,rgba(255,255,255,.025) 0 .4rem,transparent .4rem .8rem)}
.folio.gen .fh{background-color:#5c1620}
.fh::after{content:"";position:absolute;inset:.35rem;border:1px solid rgba(212,178,107,.35);pointer-events:none}
.fnum{font:600 3.4rem/0.85 var(--display);color:#e9cf8f;font-variant-numeric:lining-nums;letter-spacing:.02em;text-shadow:0 1px 0 rgba(0,0,0,.3)}
.fcap{display:flex;flex-direction:column;line-height:1.25;padding-bottom:.2rem}
.fcap span{font:italic 500 .82rem var(--display);letter-spacing:.08em;color:#d4b26b}
.fcap b{font-size:1rem;letter-spacing:.12em;font-weight:600}
.fb{padding:1rem 1.2rem .4rem;flex:1}
.fb h2{margin:0;font:600 1.18rem/1.35 var(--serif);color:var(--fg)}
.fsrc{margin:.2rem 0 .7rem;font-size:.8rem;color:var(--sub);letter-spacing:.04em}
.fstat{min-height:1.9rem}
.best{font-family:var(--display);color:var(--ok);font-size:.9rem}.best b{font-size:1.6rem;margin:0 .15rem;font-variant-numeric:lining-nums}.best small{color:var(--sub)}
.todo{display:inline-block;font-size:.78rem;letter-spacing:.1em;color:var(--sub);border:1px dashed var(--rule);padding:.05rem .6rem;border-radius:2rem}
.scale{padding:1.3rem 0 1.5rem}
.track{position:relative;height:.3rem;border-radius:1rem;background:linear-gradient(90deg,var(--mu) 0%,color-mix(in srgb,var(--gold) 45%,var(--mu)) 60%,var(--gold) 100%)}
.tk{position:absolute;top:50%;transform:translate(-50%,-50%);width:.55rem;height:.55rem;background:var(--sf);border:.12rem solid var(--acc);border-radius:50%;font-style:normal}
.tk b{position:absolute;bottom:.75rem;left:50%;transform:translateX(-50%);font:700 .72rem var(--display);color:var(--acc)}
.tk span{position:absolute;top:.75rem;left:50%;transform:translateX(-50%);font-size:.66rem;color:var(--sub);font-variant-numeric:lining-nums tabular-nums;white-space:nowrap}
.me{position:absolute;top:50%;transform:translate(-50%,-50%) rotate(45deg);width:.7rem;height:.7rem;background:var(--ok);border:.12rem solid var(--sf)}
.ff{display:flex;align-items:center;gap:.8rem;padding:.8rem 1.2rem 1rem;border-top:1px solid var(--bd);background:color-mix(in srgb,var(--paper) 60%,var(--sf))}
.ff .go{flex:1;justify-content:center;text-align:center;background:var(--acc);border-color:var(--acc);color:#fbf6ea;letter-spacing:.12em}
.ff .alt{display:flex;gap:.9rem}
.ff .alt a{font-size:.88rem;color:var(--br);text-decoration:none;border-bottom:1px solid var(--rule);padding:.5rem 0 .05rem;white-space:nowrap}
.ff .alt a:hover{color:var(--acc);border-color:var(--acc)}
:root.dark .ff .go{color:#0e1524}
@media (prefers-color-scheme:dark){:root:not(.light) .ff .go{color:#0e1524}}
.ff .alt a{font-style:normal}
.scale{padding-top:.4rem}.scale>div{padding-top:1.1rem}
.sl{display:block;font-size:.68rem;letter-spacing:.12em;color:var(--sub)}
.fpdf{display:flex;align-items:baseline;gap:.6rem;justify-content:center;padding:.55rem 1rem;border-top:1px solid var(--bd);font-size:.85rem;color:var(--br);text-decoration:none;letter-spacing:.06em;background:var(--sf)}
.fpdf small{font-size:.7rem;color:var(--sub);letter-spacing:.04em}
.fpdf:hover{background:var(--mu);color:var(--acc)}
.opts.p .opt>span:last-child{flex:1;min-width:0}.optpic{display:block;width:100%;max-height:none;height:auto;max-width:22rem}
/* 中文翻譯與字級一致 */
.zh{display:block;margin-top:.15rem;font-size:.92em;line-height:1.55;color:var(--sub);font-family:var(--serif)}
body.nozh .zh{display:none}
.tr button{font-size:1em}.tr button>span{display:block}
.big .tr,.big .exb,.big .exb td,.big .exb caption,.big .tr button{font-size:1.45rem}
.exb,.exb td{font-size:1rem}.exb caption{font-size:1rem;margin:.6rem 0 .2rem}
.exb td:last-child{white-space:nowrap;width:1%}.exb .chip{white-space:nowrap}
.big .opt .zh{font-size:.8em}
.tgrid{grid-template-columns:repeat(auto-fill,minmax(16.5rem,1fr));gap:1.2rem}
.tcard{display:flex;flex-direction:column;background:var(--sf);border:1px solid var(--bd);border-top:.25rem solid var(--br);border-radius:.25rem;padding:1.1rem 1.2rem 1rem;box-shadow:0 .6rem 1.4rem -.9rem rgba(15,44,79,.35)}
.tcard h2{margin:.2rem 0 .1rem}.tcard .sub{margin:0 0 1rem}
.tact{margin-top:auto;display:flex;gap:.5rem;flex-wrap:wrap}.tact .go{flex:1;justify-content:center;background:var(--acc);border-color:var(--acc);color:#fbf6ea}
.tact .ghost{white-space:nowrap}
.tact .btn{white-space:nowrap;padding-left:.9rem;padding-right:.9rem}

/* ===== 檢討考卷：教學工作台（左右可拖曳、分頁聚焦） ===== */
body.presenting .top,body.presenting footer{display:none}
body.presenting main{max-width:none;padding:0;margin:0}
.pv{height:100vh;display:flex;flex-direction:column;background:var(--bg)}
.pv-bar{display:flex;align-items:center;gap:.6rem;flex-wrap:wrap;padding:.5rem .9rem;background:#0f2c4f;color:#f4ecd8;border-bottom:.2rem solid var(--gold)}
.pv-bar .btn.sm{min-height:2.3rem;padding:0 .75rem;font-size:.9rem}
.pv-bar .btn.ghost{background:transparent;color:#efe5cc;border-color:rgba(212,178,107,.55)}
.pv-bar .btn.ghost:hover{background:rgba(212,178,107,.14)}.pv-bar .btn.ghost.on{background:#d4b26b;color:#0f2c4f;border-color:#d4b26b}
.pv-bar .btn:not(.ghost){background:var(--acc);border-color:var(--acc);color:#fbf6ea;min-width:6.2rem}
.pv-bar kbd{font:500 .68rem var(--serif);border:1px solid currentColor;border-radius:.2rem;padding:0 .25rem;margin-left:.25rem;opacity:.75}
.pv-title{display:flex;flex-direction:column;line-height:1.2;min-width:0}.pv-title b{font-size:1rem;white-space:nowrap}.pv-title span{font-size:.75rem;color:#d4b26b;letter-spacing:.06em}
.pv-nav{display:flex;align-items:center;gap:.3rem}.pv-nav .btn{font-size:1.2rem!important;width:2.3rem;padding:0!important;justify-content:center}
.pv-nav select{height:2.3rem;border-radius:.3rem;border:1px solid rgba(212,178,107,.55);background:#0b2240;color:#f4ecd8;font:600 .9rem var(--serif);padding:0 .4rem}
.pv-audio{display:flex;align-items:center;gap:.4rem;flex:1;min-width:14rem}
.pv-prog{flex:1;height:.45rem;border-radius:1rem;background:rgba(255,255,255,.18);cursor:pointer;position:relative;overflow:hidden}.pv-prog i{position:absolute;inset:0 auto 0 0;background:#d4b26b;width:0}
.pv-tm{font:500 .85rem var(--serif);font-variant-numeric:tabular-nums;color:#e6dcc4;white-space:nowrap}
.pv-tools{display:flex;align-items:center;gap:.35rem;flex-wrap:wrap}
.pv-lay{display:flex;border:1px solid rgba(212,178,107,.55);border-radius:.3rem;overflow:hidden}
.lay{width:2.4rem;height:2.3rem;background:none;border:0;cursor:pointer;display:grid;place-items:center}.lay+.lay{border-left:1px solid rgba(212,178,107,.35)}
.lay i{display:block;width:1.3rem;height:.95rem;border:1.5px solid #e6dcc4;border-radius:2px;position:relative}
.lay i.l1{background:#e6dcc4}.lay i.l2{background:linear-gradient(90deg,#e6dcc4 50%,transparent 50%)}.lay i.l3{background:linear-gradient(90deg,transparent 18%,#e6dcc4 18%)}
.lay.on{background:#d4b26b}.lay.on i{border-color:#0f2c4f}.lay.on i.l1,.lay.on i.l2,.lay.on i.l3{background-color:transparent}.lay.on i.l1{background:#0f2c4f}.lay.on i.l2{background:linear-gradient(90deg,#0f2c4f 50%,transparent 50%)}.lay.on i.l3{background:linear-gradient(90deg,transparent 18%,#0f2c4f 18%)}
.pv-stage{--l:56;flex:1;min-height:0;display:grid;grid-template-columns:calc((100% - 14px) * var(--l) / 100) 14px 1fr;padding:.7rem .9rem .9rem;gap:0}
.pv-stage.only-l{grid-template-columns:1fr 14px 0}.pv-stage.only-r{grid-template-columns:0 14px 1fr}
.pv-stage.only-l #pr1,.pv-stage.only-r #pl1{visibility:hidden;min-width:0;padding:0;border:0}
.pv-stage.drag{cursor:col-resize;user-select:none}
.pane{min-width:0;min-height:0;display:flex;flex-direction:column;background:var(--sf);border:1px solid var(--bd);border-radius:.4rem;box-shadow:0 .6rem 1.4rem -1rem rgba(15,44,79,.4);overflow:hidden}
.ph{display:flex;align-items:center;gap:.6rem;padding:.35rem .5rem .35rem .9rem;border-bottom:1px solid var(--bd);background:var(--paper);min-height:2.9rem}
.ph .pl{font:600 .85rem var(--display);letter-spacing:.3em;color:var(--acc)}
.zm{margin-left:auto;display:flex;align-items:center;gap:.25rem}
.zm button{min-height:2.1rem;min-width:2.3rem;border:1px solid var(--bd);background:var(--sf);color:var(--fg);border-radius:.25rem;font:600 .85rem var(--serif);cursor:pointer;padding:0 .5rem}
.zm button:hover{border-color:var(--gold)}.zm button.on{background:var(--br);color:var(--brf);border-color:var(--br)}
.zm b{font:500 .8rem var(--serif);color:var(--sub);min-width:2.8rem;text-align:center;font-variant-numeric:tabular-nums}
.tabs{display:flex;gap:.2rem}
.tabs button{border:0;background:none;padding:.45rem .9rem;font:600 1rem var(--serif);color:var(--sub);border-bottom:.18rem solid transparent;cursor:pointer;letter-spacing:.08em}
.tabs button kbd{font:500 .65rem var(--serif);border:1px solid currentColor;border-radius:.2rem;padding:0 .22rem;margin-left:.2rem;opacity:.6}
.tabs button.on{color:var(--acc);border-bottom-color:var(--acc)}
.pb{flex:1;min-height:0;overflow:auto;padding:1.1rem 1.4rem 2rem;font-size:1em}
#left .big{font-size:1.55em}#left .big .opt{font-size:.94em}
#right{font-size:1em}#right .tr{max-height:none!important;font-size:1.45em}#right .tr button{font-size:1em}
#right .exb,#right .vt{font-size:1.45em}#right .exb p,#right .exb td,#right .vt td{font-size:1em}#right .vt{width:100%}#right .vt td{padding:.6rem .5rem}#right .vt td:last-child{width:1%;white-space:nowrap}
#right .tr button{transition:opacity .3s}#right.spot .tr:has(.act) button:not(.act){opacity:.28}
#right .sub[style*=".75rem"]{font-size:.8rem!important}
.gut{cursor:col-resize;display:grid;place-items:center;touch-action:none}
.gut span{width:4px;height:3.2rem;border-radius:3px;background:var(--rule);box-shadow:0 0 0 3px var(--bg)}
.gut:hover span,.gut:focus-visible span,.pv-stage.drag .gut span{background:var(--acc);height:5rem}
.pv-hold{height:100%;min-height:18rem;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;gap:.6rem}
.pv-hold b{font:700 4.5rem/1 var(--serif);color:var(--br)}.pv-hold span{color:var(--acc);letter-spacing:.2em}.pv-hold p{color:var(--sub);font-size:1.3rem}
.pv-hold kbd{border:1px solid var(--rule);border-radius:.2rem;padding:0 .35rem}
.pv-ans{font:700 2.6rem var(--serif);color:var(--ok);border:2px solid var(--ok);border-radius:.4rem;padding:.3rem 1.4rem;margin-top:.8rem}
@media (max-width:900px){.pv-stage,.pv-stage.only-l,.pv-stage.only-r{grid-template-columns:1fr;grid-template-rows:auto auto}.gut{display:none}.pv-stage.only-l #pr1,.pv-stage.only-r #pl1{visibility:visible}.pv{height:auto;min-height:100vh}.pane{min-height:60vh}}
.tabs button,.zm button{white-space:nowrap}.tabs button{padding:.45rem .7rem}@media (max-width:1400px){.tabs button kbd,.pv-bar kbd{display:none}}

/* 頂部品牌：白色 KC 標誌＋分隔線＋雙行字 */
.kc{background:none;box-shadow:none;padding:0}
.kc img{height:2.1rem}
.top .sep{width:1px;height:2.1rem;background:linear-gradient(transparent,rgba(212,178,107,.85),transparent);flex:0 0 1px}
.brand{gap:.3rem;justify-content:center}
.brand b{font:700 1.08rem/1 var(--serif);letter-spacing:.1em;color:#fff}
.brand small{font:600 .6rem/1 var(--serif);letter-spacing:.26em;color:#d4b26b;font-variant:normal}
@media(max-width:760px){.kc img{height:1.5rem}.top .sep{display:none}}