:root{
  --paper:#F6F1E4; --paper-card:#FFFDF7; --ink:#221F1A; --ink-soft:#5B5648;
  --rule:#DCD3BB; --crimson:#AE3626; --sage:#3E6E52; --gold:#A9812E;
  --shadow: 0 1px 0 rgba(34,31,26,.06), 0 8px 24px rgba(34,31,26,.08);
}
*{box-sizing:border-box;}
html,body{margin:0;padding:0;}
body{
  background:var(--paper);
  background-image:
    radial-gradient(circle at 100% 0%, rgba(174,54,38,.05), transparent 40%),
    repeating-linear-gradient(0deg, rgba(34,31,26,0.025) 0px, rgba(34,31,26,0.025) 1px, transparent 1px, transparent 34px);
  color:var(--ink); font-family:'Noto Sans TC',sans-serif;
  min-height:100vh; padding:28px 16px 56px; line-height:1.75;
}
.wrap{max-width:760px; margin:0 auto;}
a{color:var(--crimson);}
.crumb{font-size:12.5px; color:var(--ink-soft); font-family:'IBM Plex Mono',monospace; margin-bottom:14px;}
.crumb a{color:var(--ink-soft); text-decoration:none; border-bottom:1px dotted var(--rule);}
.crumb a:hover{color:var(--crimson);}
.card{background:var(--paper-card); border:1px solid var(--rule); border-radius:4px;
  box-shadow:var(--shadow); padding:24px; margin-bottom:18px;}
h1{font-family:'Noto Serif TC',serif; font-weight:900; font-size:23px; margin:0 0 6px; letter-spacing:.02em;}
h2{font-family:'Noto Serif TC',serif; font-weight:700; font-size:17px; margin:0 0 12px;
  padding-bottom:8px; border-bottom:2px solid var(--rule);}
.lead{font-size:13.5px; color:var(--ink-soft); margin:0 0 16px;}
.tags{display:flex; flex-wrap:wrap; gap:7px; margin:12px 0 0;}
.tag{font-size:12px; padding:3px 10px; border-radius:999px; border:1px solid var(--rule);
  background:#fff; color:var(--ink-soft); font-family:'IBM Plex Mono',monospace;}
.tag.cat{border-color:var(--sage); color:var(--sage); background:#F2F7F1;}
.tag.hard{border-color:var(--crimson); color:var(--crimson); background:#FBF1EE;}
.tag.span{border-color:var(--gold); color:#8a6d00; background:#FBF6E9;}
.statnote{margin:12px 0 0; padding:9px 12px; background:#FBF8EE; border:1px dashed var(--rule);
  border-radius:4px; font-size:12.5px; color:var(--ink-soft); line-height:1.8;}
.statnote b{color:var(--ink);}
.statnote b.warn{color:var(--crimson);}
.stem{font-family:'Lora',serif; font-size:17px; line-height:1.95; margin:4px 0 0;}
.sblank{display:inline-block; min-width:44px; text-align:center; border-bottom:2px solid var(--crimson);
  color:var(--crimson); font-family:'IBM Plex Mono',monospace; font-weight:600; padding:0 6px;}
ol.opts{list-style:none; margin:18px 0 0; padding:0;}
ol.opts li{border:1.5px solid var(--rule); border-radius:4px; background:#fff; padding:10px 14px;
  margin-bottom:8px; font-family:'Lora',serif; font-size:15.5px;}
ol.opts li.right{border-color:var(--sage); background:#F2F7F1;}
ol.opts li .k{font-family:'IBM Plex Mono',monospace; font-weight:600; color:var(--ink-soft); margin-right:10px;}
ol.opts li.right .k{color:var(--sage);}
.ans{margin-top:14px; font-size:14.5px;}
.ans b{color:var(--sage); font-size:17px; font-family:'IBM Plex Mono',monospace;}
.why{margin:0; font-size:14.5px; line-height:1.85;}
.readmore{margin-top:14px; padding:12px 14px; border-left:3px solid var(--sage);
  background:#F2F7F1; border-radius:0 4px 4px 0; font-size:13px; line-height:1.8;}
.readmore .rm-hint{color:var(--ink-soft); margin-bottom:6px;}
.readmore a{color:var(--sage); font-weight:700;}
.report-link{display:inline-block; margin-top:7px; color:var(--crimson);
  font-family:'IBM Plex Mono',monospace; font-size:12px;}
.qcode{margin-top:16px; padding-top:12px; border-top:1px dashed var(--rule);
  font-size:11.5px; color:var(--ink-soft); font-family:'IBM Plex Mono',monospace;}
.qcode b{color:var(--crimson); font-size:13px; letter-spacing:.04em;}
.sec{margin-bottom:18px;}
.sec.lead{margin-bottom:16px; padding-bottom:14px; border-bottom:1px dashed var(--rule);}
.sec.lead p{color:var(--ink-soft); font-size:13.5px;}
.sec:last-child{margin-bottom:0;}
.sec h3{font-family:'Noto Serif TC',serif; font-weight:700; font-size:15px; color:var(--sage);
  margin:0 0 6px;}
.sec p{margin:0; font-size:14.5px; line-height:1.85;}
.srcbox{margin-top:16px; padding:12px 14px; border:1px dashed var(--rule); border-radius:4px;
  background:#FBF8EE; font-size:12px; color:var(--ink-soft); line-height:1.85;}
.srcbox b{color:var(--ink);}
.srcbox a{color:var(--crimson);}
.note-extra{border-left:3px solid var(--gold); background:#FBF6E9; padding:12px 14px;
  font-size:13.5px; margin-top:14px; border-radius:0 4px 4px 0;}
details.psg{border:1px solid var(--rule); border-radius:4px; background:#fff; padding:0; overflow:hidden;}
details.psg summary{cursor:pointer; padding:12px 16px; font-weight:500; font-size:14.5px;
  font-family:'Noto Serif TC',serif; background:#FBF8EE; list-style:none; display:flex; align-items:center;}
details.psg summary::-webkit-details-marker{display:none;}
details.psg summary::marker{content:"";}
details.psg summary::before{content:"▸"; color:var(--crimson); font-size:15px;
  margin-right:9px; display:inline-block; transition:transform .15s ease;}
details.psg[open] summary::before{transform:rotate(90deg);}
details.psg summary:focus-visible{outline:2px solid var(--crimson); outline-offset:-2px;}
@media (prefers-reduced-motion: reduce){ details.psg summary::before{transition:none;} }
details.psg .inner{padding:4px 16px 16px; font-family:'Lora',serif; font-size:15px; line-height:1.95;}
details.psg .zh{font-family:'Noto Sans TC',sans-serif; font-size:14px; color:var(--ink-soft);
  border-top:1px dashed var(--rule); padding-top:14px; margin-top:6px; line-height:1.85;}
.pblank{display:inline-block; min-width:26px; text-align:center; border-bottom:1.5px solid var(--rule);
  color:var(--ink-soft); font-family:'IBM Plex Mono',monospace; font-size:13px; padding:0 4px;}
.pblank.cur{border-color:var(--crimson); color:var(--crimson); font-weight:600; background:#FBF1EE;}
.legend{display:flex; flex-wrap:wrap; gap:12px; padding:10px 0 12px; margin-bottom:6px;
  border-bottom:1px dashed var(--rule); font-family:'Noto Sans TC',sans-serif; font-size:11.5px;
  color:var(--ink-soft);}
.legend .lg{display:inline-flex; align-items:center; gap:5px;}
.legend i{display:inline-block; width:13px; height:13px; border-radius:2px; border:1px solid var(--rule);}
/* 標記樣式沿用 index.html 的 .hint-on 狀態，色碼勿自行更動 */
.dual-role{background:#D4EBC4; box-shadow:inset 0 -2px 0 #7CA85C;}
.main-thesis{background:#CFE3F5; box-shadow:inset 0 -2px 0 #6FA8DC;}
.topic-sent{background:#FDF3B8;}
.trans-word{color:var(--crimson); font-weight:700;}
.legend i.trans-word{background:transparent; border-color:transparent;
  width:auto; height:auto; font-family:'Lora',serif; font-size:12.5px; line-height:1.2;}
.nav{display:flex; justify-content:space-between; gap:10px; margin-top:4px;}
.nav a{flex:1; text-align:center; padding:11px 8px; border:1.5px solid var(--rule); border-radius:4px;
  background:#fff; text-decoration:none; font-size:13.5px; color:var(--ink-soft);}
.nav a:hover{border-color:var(--crimson); color:var(--crimson);}
.nav span{flex:1;}
.qlist{list-style:none; margin:0; padding:0;}
.qlist li{border-bottom:1px solid var(--rule);}
.qlist li:last-child{border-bottom:none;}
.qlist a{display:block; padding:13px 4px; text-decoration:none; color:var(--ink);}
.qlist a:hover{background:#FBF8EE;}
.qlist .no{font-family:'IBM Plex Mono',monospace; color:var(--crimson); font-weight:600;
  margin-right:10px; font-size:14px;}
.qlist .ct{font-size:13.5px; color:var(--ink-soft);}
.qlist .pv{font-family:'IBM Plex Mono',monospace; font-size:12px; color:var(--ink-soft); float:right;
  padding:1px 8px; border-radius:999px; border:1px solid transparent;}
.qlist .pv.hard{color:var(--crimson); border-color:var(--crimson); background:#FBF1EE; font-weight:600;}
.qlist .pv.easy{color:var(--sage); border-color:#CBDDCB; background:#F2F7F1;}
.ygrid{display:grid; grid-template-columns:repeat(auto-fill,minmax(150px,1fr)); gap:10px;}
.ygrid a{display:block; border:1.5px solid var(--rule); border-radius:4px; background:#fff;
  padding:14px 12px; text-decoration:none; color:var(--ink);}
.ygrid a:hover{border-color:var(--crimson);}
.ygrid .yn{font-family:'Noto Serif TC',serif; font-weight:700; font-size:15px; display:block;}
.ygrid .yc{font-size:12px; color:var(--ink-soft); font-family:'IBM Plex Mono',monospace;}
.hardlist{list-style:none; margin:0; padding:0; counter-reset:hd;}
.hardlist li{border-bottom:1px solid var(--rule);}
.hardlist li:last-child{border-bottom:none;}
.hardlist a{display:block; padding:15px 4px; text-decoration:none; color:var(--ink);}
.hardlist a:hover{background:#FBF8EE;}
.hardlist .rank{display:inline-block; min-width:34px; font-family:'IBM Plex Mono',monospace;
  font-size:13px; color:var(--crimson); font-weight:600;}
.hardlist .ttl{font-family:'Noto Serif TC',serif; font-weight:700; font-size:15px;}
.hardlist .pct{float:right; font-family:'IBM Plex Mono',monospace; font-size:13px; font-weight:600;
  color:var(--crimson); background:#FBF1EE; border:1px solid var(--crimson);
  border-radius:999px; padding:2px 10px;}
.hardlist .tie{font-family:'Noto Sans TC',sans-serif; font-size:11px; color:var(--ink-soft);
  border:1px solid var(--rule); border-radius:999px; padding:1px 7px; margin-left:8px;
  vertical-align:2px;}
.hardlist .meta{display:block; margin:5px 0 0 34px; font-size:12.5px; color:var(--ink-soft);}
.hardlist .teaser{display:block; margin:6px 0 0 34px; font-size:13px; color:var(--ink-soft);
  line-height:1.75;}
.hero{background:var(--crimson); color:#fff; border:none;}
.hero h1{color:#fff; margin-bottom:10px;}
.hero p{color:#fff; opacity:.94; font-size:14px; margin:0; line-height:1.85;}
.hero .big{font-family:'IBM Plex Mono',monospace; font-weight:600; font-size:15px;}
.bigentry{display:block; text-decoration:none; background:var(--crimson); color:#fff;
  border-radius:4px; padding:22px 24px; margin-bottom:18px; box-shadow:var(--shadow);}
.bigentry:hover{background:#95291b;}
.be-eyebrow{display:block; font-family:'IBM Plex Mono',monospace; font-size:11.5px;
  letter-spacing:.16em; opacity:.85; margin-bottom:7px;}
.be-title{display:block; font-family:'Noto Serif TC',serif; font-weight:900; font-size:24px;
  line-height:1.3; margin-bottom:9px;}
.be-sub{display:block; font-size:13.5px; line-height:1.8; opacity:.94;}
.be-go{display:inline-block; margin-top:14px; border:1.5px solid rgba(255,255,255,.6);
  border-radius:999px; padding:7px 18px; font-size:13.5px; font-weight:700;}
.bigentry:hover .be-go{background:#fff; color:var(--crimson); border-color:#fff;}
@media (max-width:560px){ .bigentry{padding:18px 18px;} .be-title{font-size:20px;} }
.cta{display:block; text-align:center; padding:14px; border:2px solid var(--sage); border-radius:4px;
  background:#F2F7F1; color:var(--sage); text-decoration:none; font-weight:700; font-size:15px;}
.cta:hover{background:var(--sage); color:#fff;}
footer .fb{color:var(--ink-soft);}
footer .fb a{color:var(--crimson); font-weight:600;}
footer{margin-top:26px; font-size:11.5px; color:var(--ink-soft); text-align:center; line-height:1.8;}
@media (max-width:560px){ body{padding:20px 12px 44px;} .card{padding:18px;} h1{font-size:20px;} }

/* 段落大意：獨立摺疊區塊，沿用 index.html 的 .outline-box 樣式 */
details.outline summary{cursor:pointer; padding:12px 16px; font-weight:500; font-size:14.5px;
  font-family:'Noto Serif TC',serif; background:#F7F5F0; list-style:none; display:flex; align-items:center;}
details.outline summary::-webkit-details-marker{display:none;}
details.outline summary::marker{content:"";}
details.outline summary::before{content:"▸"; color:var(--crimson); font-size:15px; margin-right:9px;
  display:inline-block; transition:transform .15s ease;}
details.outline[open] summary::before{transform:rotate(90deg);}
details.outline summary:focus-visible{outline:2px solid var(--crimson); outline-offset:-2px;}
@media (prefers-reduced-motion: reduce){ details.outline summary::before{transition:none;} }
details.outline{border:1px solid var(--rule); border-radius:4px; background:#fff; overflow:hidden;}
details.outline ol{margin:0; padding:4px 16px 16px 38px; font-size:13.5px; color:var(--ink-soft);
  line-height:1.85;}
details.outline ol li{margin-bottom:8px;}
details.outline ol li:last-child{margin-bottom:0;}