/* ============================================================
   15040 备考工作台 — 朱批书案（水墨纸面 · 朱红批注）
   ============================================================ */
:root {
  --paper:      #f6f2ea;
  --paper-2:    #fffdf8;
  --paper-3:    #efe9de;
  --ink:        #1d1a15;
  --ink-2:      #585047;
  --ink-3:      #6f665c;
  --line:       #e3dacd;
  --line-2:     #d2c6b4;
  --red:        #a32114;
  --red-2:      #c33a22;
  --red-tint:   #f6e7e2;
  --green:      #2c6450;
  --green-tint: #e4ede6;
  --gold:       #a2791f;
  --gold-tint:  #f6edd9;
  --radius:     14px;
  --radius-sm:  9px;
  --rail-w:     252px;
  /* 间距刻度：4 为基数，避免到处出现一次性数值 */
  --s1: 4px;  --s2: 8px;  --s3: 12px; --s4: 16px; --s5: 24px; --s6: 32px; --s7: 44px;
  --sans: "Segoe UI", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, sans-serif;
  --kai: "KaiTi", "STKaiti", "楷体", "Kaiti SC", serif;
  --rule: 1px solid var(--line);
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
::selection { background: #f0d3cc; color: #6d1a10; }
:focus-visible { outline: 2px solid var(--red-2); outline-offset: 2px; border-radius: 4px; }
button { font: inherit; color: inherit; }
input, select, textarea { font: inherit; color: inherit; caret-color: var(--red); }
a { color: var(--red); text-decoration-thickness: 1px; text-underline-offset: 3px; }
h1, h2, h3, h4 { margin: 0; font-weight: 650; letter-spacing: -0.012em; }
p { margin: 0 0 .7em; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 12px; top: 12px; z-index: 40; background: var(--paper-2); padding: 8px 12px; border: var(--rule); border-radius: 8px; }

/* scrollbars tuned to the paper palette */
* { scrollbar-color: #c9bda9 transparent; scrollbar-width: thin; }
*::-webkit-scrollbar { width: 11px; height: 11px; }
*::-webkit-scrollbar-track { background: transparent; }
*::-webkit-scrollbar-thumb { background: #ccbfaa; border: 3px solid var(--paper); border-radius: 9px; }
*::-webkit-scrollbar-thumb:hover { background: #b3a48c; }

/* ---------------------------------------------------------- shell */
.shell { display: grid; grid-template-columns: var(--rail-w) minmax(0, 1fr); min-height: 100vh; }
.rail {
  position: sticky; top: 0; align-self: start; height: 100vh;
  display: flex; flex-direction: column;
  background: var(--paper-2);
  border-right: var(--rule);
  padding: 20px 16px 16px;
  gap: 14px;
}
.rail-head { display: grid; gap: 12px; }
.brand { display: flex; align-items: center; gap: 10px; }
.seal { width: 34px; height: 34px; color: var(--red); flex: none; }
.brand-text { display: grid; line-height: 1.25; }
.brand-text strong { font-family: var(--kai); font-size: 19px; letter-spacing: .01em; }
.brand-text span { font-size: 12px; color: var(--ink-3); letter-spacing: .04em; }
.rail-note { font-size: 12px; color: var(--ink-3); line-height: 1.55; margin: 0; }

.rail-nav { display: grid; gap: 2px; }
.nav-item {
  display: flex; align-items: center; gap: 10px;
  background: none; border: 0; cursor: pointer;
  padding: 9px 10px; border-radius: var(--radius-sm);
  color: var(--ink-2); text-align: left; font-size: 14.5px;
  transition: background .15s ease, color .15s ease;
}
.nav-item em { margin-left: auto; font-style: normal; font-size: 11.5px; color: var(--ink-3); font-variant-numeric: tabular-nums; }
.nav-item:hover { background: var(--paper-3); color: var(--ink); }
.nav-item[aria-current="page"] { background: var(--red-tint); color: var(--red); font-weight: 600; }
.nav-item[aria-current="page"] em { color: var(--red); }
.nav-ico { display: inline-flex; width: 20px; height: 20px; color: currentColor; flex: none; }
.nav-ico svg { width: 20px; height: 20px; }

.rail-foot { margin-top: auto; display: grid; gap: 10px; }
.meter-bar { height: 5px; background: var(--paper-3); border-radius: 99px; overflow: hidden; }
.meter-bar i { display: block; height: 100%; background: var(--red); border-radius: 99px; transition: width .4s cubic-bezier(.16,.84,.3,1); }
.meter-meta { display: flex; justify-content: space-between; font-size: 11.5px; color: var(--ink-3); font-variant-numeric: tabular-nums; }
.ghost-btn {
  background: none; border: var(--rule); border-radius: var(--radius-sm);
  padding: 7px 10px; font-size: 12.5px; color: var(--ink-3); cursor: pointer;
  transition: color .15s ease, border-color .15s ease, background .15s ease;
}
.ghost-btn:hover { color: var(--red); border-color: var(--red-2); background: var(--red-tint); }

/* ---------------------------------------------------------- main */
.main { min-width: 0; padding: 34px 40px 72px; }
.main { padding-left: max(40px, env(safe-area-inset-left)); padding-right: max(40px, env(safe-area-inset-right)); }
.view-root { max-width: 1160px; margin: 0 auto; animation: view-in .22s cubic-bezier(.2,.8,.3,1); }
.view-root.no-anim { animation: none; }
@keyframes view-in { from { opacity: 0; transform: translateY(4px); } to { opacity: 1; transform: none; } }

.page-head { display: grid; gap: 6px; margin-bottom: 26px; }
.page-head h1 { font-family: var(--kai); font-size: clamp(26px, 3vw, 34px); font-weight: 600; }
.page-head .sub { color: var(--ink-2); font-size: 14px; max-width: min(70ch, 100%); margin: 0; }
.rule { height: 2px; width: 46px; background: var(--red); border-radius: 2px; margin: 10px 0 0; }

.eyebrow { font-size: 12px; letter-spacing: .12em; color: var(--ink-3); }

/* ---------------------------------------------------------- quiz */
.quiz-wrap { display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: 34px; align-items: start; }
.quiz-main { min-width: 0; }
.quiz-aside { display: grid; gap: 18px; position: sticky; top: 28px; }

.qbar { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; margin-bottom: 14px; }
.filter-toggle { display: none; }
.filters .qbar { margin-bottom: 14px; }

/* 刷题页：题目下方才是「从第几题开始」和练习设置 */
.jump-block { margin-top: 20px; border-top: var(--rule); padding-top: 14px; }
.jump-row { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.jump-input {
  width: 84px; padding: 8px 10px; text-align: center;
  border: var(--rule); border-radius: var(--radius-sm); background: var(--paper-2);
  font-variant-numeric: tabular-nums;
}
.filters { margin-top: 16px; border-top: var(--rule); padding-top: 14px; }
.filters .filter-toggle b { color: var(--ink); }
@media (max-width: 900px) {
  .filter-toggle {
    display: flex; align-items: center; justify-content: space-between; gap: 10px;
    width: 100%; min-height: 44px; text-align: left;
    background: var(--paper-2); border: var(--rule); border-radius: var(--radius-sm);
    padding: 10px 12px; font-size: 13.5px; color: var(--ink-2); cursor: pointer;
  }
  .filter-toggle .filter-caret { color: var(--red); font-weight: 600; flex: none; }
  .filters:not(.open) > .qbar { display: none; }
  .filters.open .filter-toggle { border-color: var(--line-2); }
}
.qbar .spacer { flex: 1; }
.pill {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 12.5px; padding: 4px 9px; border-radius: 99px;
  background: var(--paper-3); color: var(--ink-2); font-variant-numeric: tabular-nums;
}
.pill.red { background: var(--red-tint); color: var(--red); }
.pill.green { background: var(--green-tint); color: var(--green); }
.pill.gold { background: var(--gold-tint); color: var(--gold); }

.stem { font-size: 17.5px; line-height: 1.8; margin: 6px 0 20px; max-width: min(72ch, 100%); }
.stem .num { color: var(--ink-3); font-size: 13px; margin-right: 8px; font-variant-numeric: tabular-nums; }
.tap-tip { font-size: 12.5px; color: var(--red); margin: -12px 0 12px; }

.opts { display: grid; gap: 9px; }
.opt {
  display: flex; gap: 12px; align-items: flex-start; width: 100%;
  background: var(--paper-2); border: var(--rule); border-radius: var(--radius-sm);
  padding: 13px 15px; cursor: pointer; text-align: left; line-height: 1.65;
  transition: border-color .15s ease, background .15s ease, transform .1s ease;
}
.opt:hover { border-color: var(--line-2); background: #fffefb; }
.opt:active { transform: translateY(1px); }
.opt .key {
  flex: none; width: 24px; height: 24px; border-radius: 7px; display: grid; place-items: center;
  background: var(--paper-3); font-size: 13px; font-weight: 600; color: var(--ink-2);
  font-variant-numeric: tabular-nums; transition: background .15s ease, color .15s ease;
}
.opt[aria-pressed="true"] { border-color: var(--red-2); background: var(--red-tint); }
.opt[aria-pressed="true"] .key { background: var(--red); color: #fff; }
.opt.correct { border-color: #9fbcaa; background: var(--green-tint); }
.opt.correct .key { background: var(--green); color: #fff; }
.opt.wrong { border-color: #d9a99f; background: var(--red-tint); }
.opt.wrong .key { background: var(--red); color: #fff; }
.opt.dim { opacity: .62; }

.answer-note { margin-top: 16px; padding-top: 14px; border-top: var(--rule); display: grid; gap: 8px; }
.verdict { display: flex; align-items: center; gap: 8px; font-weight: 600; }
.verdict.ok { color: var(--green); }
.verdict.no { color: var(--red); }
.explain { font-size: 14.5px; color: var(--ink-2); line-height: 1.8; max-width: min(74ch, 100%); }
.explain .lab { color: var(--ink-3); font-size: 12.5px; letter-spacing: .06em; display: block; margin-bottom: 3px; }
.explain.auto-note { background: var(--paper); border: var(--rule); border-radius: var(--radius-sm); padding: 11px 13px; }
.explain.auto-note b { color: var(--red); font-weight: 600; }

.action-row { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; margin-top: 22px; }
/* 未作答时底部这两个键：做成明确的按钮（有边框、有底色、等宽、中间留缝） */
.quiz-main .action-row.answer-actions.sticky-actions { gap: 12px; }
.quiz-main .action-row.answer-actions.sticky-actions .btn {
  flex: 1 1 0; min-height: 46px;
  display: inline-flex; align-items: center; justify-content: center;
  border-radius: 12px; font-weight: 600;
}
.quiz-main .action-row.answer-actions .qa-skip {
  background: var(--red-tint); border-color: #e2b7ad; color: var(--red);
}
.quiz-main .action-row.answer-actions .qa-skip:hover { background: var(--red); border-color: var(--red); color: #fff; }
.quiz-main .action-row.answer-actions .qa-fav { background: var(--paper-2); }
.quiz-main .action-row.answer-actions .qa-fav[aria-pressed="true"] { background: var(--gold-tint); border-color: #e0cd9f; color: var(--gold); }
/* 主观题：破题下面的四个按钮，手机上尽量排成一行 */
.subj-actions { gap: 8px; }
@media (max-width: 900px) {
  .subj-actions { gap: 6px; flex-wrap: nowrap; }
  .subj-actions .btn { flex: 1 1 auto; padding: 9px 8px; font-size: 13px; min-height: 42px; white-space: nowrap; }
}
.btn {
  border: 1px solid transparent; border-radius: var(--radius-sm); cursor: pointer;
  padding: 10px 18px; font-size: 14.5px; font-weight: 600; background: var(--red); color: #fff;
  transition: background .15s ease, transform .1s ease, box-shadow .2s ease;
}
.btn:hover { background: #8e1c11; }
.btn:active { transform: translateY(1px); }
.btn[disabled] { background: var(--paper-3); color: var(--ink-3); cursor: not-allowed; }
.btn.line { background: none; border-color: var(--line-2); color: var(--ink); }
.btn.line:hover { border-color: var(--red-2); color: var(--red); background: var(--red-tint); }
.btn.quiet { background: none; border-color: transparent; color: var(--ink-2); padding: 10px 10px; font-weight: 500; }
.btn.quiet:hover { color: var(--red); background: var(--red-tint); }
.kbd {
  font-family: ui-monospace, "Cascadia Mono", Consolas, monospace; font-size: 11.5px;
  border: var(--rule); border-bottom-width: 2px; border-radius: 5px; padding: 1px 5px; color: var(--ink-3);
  background: var(--paper-2);
}

.field { display: grid; gap: 5px; }
.field label { font-size: 12px; letter-spacing: .06em; color: var(--ink-3); }
select, input[type="text"], input[type="search"] {
  background: var(--paper-2); border: var(--rule); border-radius: var(--radius-sm);
  padding: 8px 10px; font-size: 14px; width: 100%;
}
.qbar select, .qbar input[type="text"], .qbar input[type="search"] { width: auto; min-width: 150px; }
select:hover, input:hover { border-color: var(--line-2); }

.seg { display: inline-flex; background: var(--paper-3); border-radius: var(--radius-sm); padding: 3px; gap: 2px; }
.seg button {
  border: 0; background: none; padding: 6px 12px; border-radius: 7px; cursor: pointer;
  font-size: 13.5px; color: var(--ink-2);
}
.seg button[aria-pressed="true"] { background: var(--paper-2); color: var(--ink); font-weight: 600; box-shadow: 0 1px 2px rgba(60,45,25,.12), 0 6px 14px -10px rgba(60,45,25,.3); }

.side-block { display: grid; gap: 8px; }
.side-block h3 { font-size: 13px; letter-spacing: .07em; color: var(--ink-3); font-weight: 600; }
.legend { display: grid; gap: 6px; font-size: 13px; color: var(--ink-2); }
.legend .row { display: flex; justify-content: space-between; gap: 10px; font-variant-numeric: tabular-nums; }
.legend i { display: inline-block; width: 8px; height: 8px; border-radius: 3px; margin-right: 7px; }

/* ---------------------------------------------------------- mind map */
.mind-shell { display: grid; grid-template-columns: minmax(0, 1fr) 322px; gap: 0; border-top: var(--rule); }
.mind-canvas {
  position: relative; min-height: 620px; height: calc(100vh - 292px);
  overflow: hidden; background:
    radial-gradient(120% 90% at 12% 0%, #fffdf8 0%, var(--paper) 55%, #f2ece1 100%);
  border-right: var(--rule);
}
.mind-canvas svg { display: block; width: 100%; height: 100%; cursor: grab; touch-action: none; }
.mind-canvas svg.dragging { cursor: grabbing; }
.mind-toolbar {
  display: flex; align-items: center; gap: 8px; flex-wrap: wrap;
  padding: 12px 0 12px; border-bottom: var(--rule);
}
.mind-toolbar .spacer { flex: 1; }
.chapter-tabs { display: flex; gap: 6px; flex-wrap: wrap; margin: 14px 0 14px; }
.tab {
  border: var(--rule); background: var(--paper-2); border-radius: 99px;
  padding: 5px 12px; font-size: 13px; color: var(--ink-2); cursor: pointer;
  transition: all .15s ease;
}
.tab:hover { border-color: var(--line-2); color: var(--ink); }
.tab[aria-current="true"] { background: var(--red); border-color: var(--red); color: #fff; font-weight: 600; }

.node-link { fill: none; stroke: #d8cbb6; stroke-width: 1.4; }
.node-link.hot { stroke: var(--red-2); stroke-width: 1.8; }
.node-box { fill: #fffdf8; stroke: #d8c9ad; stroke-width: 1; }
.node-box.root { fill: var(--red); stroke: var(--red); }
.node-box.box { fill: #fefaf1; stroke: #dcc79f; }
.node-box.note { fill: #fff; stroke: #b9cfc2; stroke-dasharray: 4 3; }
.node-label { font-size: 12.5px; fill: var(--ink); dominant-baseline: middle; }
.node-label.root { fill: #fff; font-family: var(--kai); font-size: 15px; }
.node-hit { fill: transparent; cursor: pointer; }
.node-g.active .node-box { stroke: var(--red); stroke-width: 1.6; }
.node-g.active .node-label { fill: var(--red); font-weight: 600; }
.node-g.active .node-box.root { stroke: #e8b4a4; stroke-width: 2; fill: #8e1c11; }
.node-g.active .node-label.root { fill: #fff; }
.node-g.dimmed { opacity: .3; }
.node-g.hit .node-box { stroke: var(--red-2); }
.node-g { transition: opacity .18s ease; }
.branch { animation: draw .5s cubic-bezier(.2,.8,.3,1) both; }
@keyframes draw { from { stroke-dashoffset: var(--len, 400); opacity: .2; } to { stroke-dashoffset: 0; opacity: 1; } }
.mind-empty { display: grid; place-items: center; height: 100%; color: var(--ink-3); }

.drawer { background: var(--paper-2); padding: 22px 22px 40px; overflow: auto; height: calc(100vh - 292px); min-height: 620px; }
.drawer h2 { font-size: 17px; line-height: 1.5; }
.drawer .path { font-size: 12.5px; color: var(--ink-3); margin: 8px 0 16px; line-height: 1.7; }
.drawer .section-title { font-size: 12px; letter-spacing: .08em; color: var(--ink-3); margin: 18px 0 8px; }
.leaf-list { margin: 0; padding: 0; list-style: none; display: grid; gap: 7px; }
.leaf-list li { display: flex; gap: 9px; font-size: 14px; line-height: 1.6; color: var(--ink-2); }
.leaf-list li::before { content: ""; width: 5px; height: 5px; border-radius: 99px; background: var(--line-2); margin-top: 9px; flex: none; }
.related { display: grid; gap: 6px; margin-top: 10px; }
.related button {
  text-align: left; background: var(--paper-3); border: 0; border-radius: 8px; padding: 9px 11px;
  font-size: 13.5px; color: var(--ink-2); cursor: pointer; line-height: 1.55;
}
.related button:hover { background: var(--red-tint); color: var(--red); }
.drawer-tools { display: grid; gap: 8px; margin-top: 16px; }
.drawer-tools .btn { width: 100%; }
.drawer-back { width: 100%; margin-top: 4px; }

/* ---------------------------------------------------------- subjective */
.subj-wrap { display: grid; grid-template-columns: 330px minmax(0, 1fr); gap: 30px; align-items: start; }
.subj-list { max-height: calc(100vh - 240px); overflow: auto; border-top: var(--rule); }
.subj-picker { border-bottom: var(--rule); }
.subj-picker summary { cursor: pointer; padding: 12px 2px; font-size: 14.5px; display: flex; gap: 10px; align-items: baseline; }
.subj-picker summary::-webkit-details-marker { display: none; }
.subj-picker summary .n { color: var(--red); font-weight: 700; }
.subj-item {
  display: grid; gap: 4px; width: 100%; text-align: left; background: none; border: 0;
  border-bottom: var(--rule); padding: 12px 12px 12px 10px; cursor: pointer; color: var(--ink-2);
}
.subj-item:hover { background: var(--paper-3); }
.subj-item[aria-current="true"] { background: var(--red-tint); color: var(--red); }
.subj-item[aria-current="true"] .meta { color: var(--red); }
.subj-item .t { font-size: 14px; line-height: 1.55; }
.subj-item .meta { font-size: 11.5px; color: var(--ink-3); font-variant-numeric: tabular-nums; }
.subj-reader { min-width: 0; }
.subj-no {
  display: inline-flex;
  align-items: center;
  margin-bottom: 9px;
  padding: 4px 10px;
  border-radius: 999px;
  background: var(--red-tint);
  color: var(--red);
  font-size: 12px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}
.subj-reader .q { font-family: var(--kai); font-size: 21px; line-height: 1.65; margin-bottom: 16px; }
.frame { display: grid; gap: 10px; margin: 18px 0 22px; }
.frame ol { margin: 0; padding-left: 0; list-style: none; display: grid; gap: 9px; }
.frame li { display: flex; gap: 11px; align-items: flex-start; font-size: 14.5px; line-height: 1.7; }
.frame .idx {
  flex: none; width: 22px; height: 22px; border-radius: 99px; display: grid; place-items: center;
  background: var(--gold-tint); color: var(--gold); font-size: 12px; font-weight: 700; margin-top: 2px;
}
.frame .mark { margin-left: auto; font-size: 12px; color: var(--ink-3); }
.answer-body { font-size: 15px; line-height: 1.9; color: var(--ink-2); max-width: min(72ch, 100%); }
.answer-body b { color: var(--ink); font-weight: 650; background: linear-gradient(transparent 62%, #f6e0c8 62%); }
.answer-body p { margin: 0 0 10px; }
.steps-note { border-top: var(--rule); border-bottom: var(--rule); padding: 14px 0; margin: 18px 0 22px; display: grid; gap: 8px; }
.steps-note .row { display: flex; gap: 10px; font-size: 13.5px; color: var(--ink-2); }
.steps-note b { color: var(--red); font-weight: 600; flex: none; }
.insight {
  display: flex; gap: 10px; align-items: baseline;
  background: var(--gold-tint); border-radius: var(--radius-sm);
  padding: 10px 13px; margin-bottom: 18px; font-size: 14.5px; line-height: 1.7; color: var(--ink);
}
.insight .lab { color: var(--gold); font-weight: 700; flex: none; font-size: 13px; letter-spacing: .04em; }
.insight-body { flex: 1 1 auto; min-width: 0; display: grid; gap: 8px; }
.insight .itext { line-height: 1.7; }
/* 破题默认模糊，点开才显示 */
.insight.blurred .itext {
  filter: blur(5px); opacity: .55;
  user-select: none; pointer-events: none;
}
.insight-reveal { justify-self: start; }
.frame-head { display: flex; align-items: center; gap: 10px; margin: 20px 0 10px; flex-wrap: wrap; }
.frame-head h2 { font-size: 15px; }
.frame-head .mark-btn { margin-left: auto; }
.kw-row { margin-top: 16px; }

/* ---------------------------------------------------------- recite */
.recite-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 14px; }
.card {
  background: var(--paper-2); border: var(--rule); border-radius: var(--radius);
  padding: 16px 17px; display: grid; gap: 10px;
}
.card .q { font-size: 14.5px; line-height: 1.7; }
.card .mask { font-family: var(--kai); font-size: 17px; color: var(--red); letter-spacing: .02em; }
.card.revealed .mask { color: var(--ink); }
.card .row { display: flex; gap: 8px; align-items: center; }
.card .row .spacer { flex: 1; }
.point-list { display: grid; gap: 6px; margin-top: 2px; }
.point-line { display: flex; gap: 8px; align-items: baseline; font-size: 14px; color: var(--ink-2); line-height: 1.65; }
.point-line .idx { color: var(--gold); font-weight: 700; flex: none; }
.point-line.opened .ptext { color: var(--ink); }
.point-open {
  border: 1px dashed var(--line-2); background: none; color: var(--ink-3);
  border-radius: 7px; padding: 2px 9px; font-size: 12.5px; cursor: pointer;
}
.point-open:hover { border-color: var(--red-2); color: var(--red); background: var(--red-tint); }
.mark-btn { background: none; border: var(--rule); border-radius: 99px; padding: 4px 11px; font-size: 12.5px; color: var(--ink-3); cursor: pointer; }
.mark-btn:hover { color: var(--red); border-color: var(--red-2); background: var(--red-tint); }
.mark-btn[aria-pressed="true"] { background: var(--green-tint); border-color: #a9c4b3; color: var(--green); }
.acc { border-bottom: var(--rule); }
.acc summary { cursor: pointer; padding: 12px 4px; font-size: 15px; display: flex; gap: 10px; align-items: baseline; }
.acc summary::-webkit-details-marker { display: none; }
.acc summary .n { color: var(--red); font: 600 13px ui-monospace, Consolas, monospace; }
.acc .body { padding: 0 4px 16px 30px; font-size: 14.5px; line-height: 1.85; color: var(--ink-2); max-width: min(72ch, 100%); }

/* ---------------------------------------------------------- method */
.method-col { max-width: min(74ch, 100%); }
.method-col h2 { font-family: var(--kai); font-size: 22px; margin: 34px 0 12px; }
.method-col h2:first-child { margin-top: 0; }
.tpl { border: var(--rule); border-radius: var(--radius); background: var(--paper-2); padding: 16px 18px; margin-bottom: 12px; }
.tpl header { display: flex; align-items: center; gap: 10px; margin-bottom: 8px; }
.tpl h3 { font-size: 15.5px; }
.tpl .body { font-size: 14.5px; line-height: 1.9; color: var(--ink-2); }
.tpl .copy { margin-left: auto; }
.trap { display: grid; gap: 4px; padding: 12px 0; border-bottom: var(--rule); }
.trap b { color: var(--red); font-size: 14.5px; }
.trap span { color: var(--ink-2); font-size: 14.5px; line-height: 1.8; }
.exam-facts { display: grid; gap: 10px; margin: 0 0 6px; }
.exam-facts .f { display: grid; grid-template-columns: 96px 1fr; gap: 14px; font-size: 14.5px; align-items: baseline; }
.exam-facts .f b { color: var(--ink-3); font-weight: 500; font-size: 13px; letter-spacing: .04em; }

/* ---------------------------------------------------------- home */
.board {
  border: var(--rule); border-left: 0; border-right: 0; border-radius: 0;
  background: linear-gradient(180deg, #fffdf8, #fbf6ec);
  padding: 22px 0 24px; display: grid; grid-template-columns: minmax(0,1.35fr) minmax(0,1fr); gap: 34px;
}
.board h2 { font-family: var(--kai); font-size: 24px; margin-bottom: 6px; }
.board .lede { color: var(--ink-2); font-size: 14.5px; max-width: min(46ch, 100%); }
.board-actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 16px; }
.ledger { display: grid; gap: 9px; align-content: start; }
.ledger-row { display: grid; grid-template-columns: 1fr auto; gap: 10px; align-items: center; font-size: 13.5px; color: var(--ink-2); }
.ledger-row .track { grid-column: 1 / -1; height: 4px; background: var(--paper-3); border-radius: 99px; overflow: hidden; }
.ledger-row .track i { display: block; height: 100%; background: var(--red-2); }
.ledger-row .track i.ok { background: #6d9a80; }
.ledger-row em { font-style: normal; font-variant-numeric: tabular-nums; color: var(--ink-3); font-size: 12.5px; }

.modules { display: grid; margin-top: 8px; }
.module {
  display: grid; grid-template-columns: 44px minmax(0,1fr) auto; gap: 16px; align-items: center;
  padding: 18px 4px; border-bottom: var(--rule); cursor: pointer; background: none; border-left: 0; border-right: 0; border-top: 0;
  text-align: left;
}
.module:hover { background: var(--paper-3); }
.module .ico { width: 44px; height: 44px; border-radius: 11px; background: var(--paper-3); display: grid; place-items: center; color: var(--red); }
.module h3 { font-size: 16.5px; margin-bottom: 2px; }
.module p { margin: 0; font-size: 13.5px; color: var(--ink-2); }
.module .go { color: var(--ink-3); }
.module > span:nth-child(2) { min-width: 0; }
.module h3, .module p { overflow-wrap: anywhere; }

.cols { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 30px; margin-top: 34px; }
.cols h3 { font-size: 13px; letter-spacing: .07em; color: var(--ink-3); margin-bottom: 10px; }
.cols ul { margin: 0; padding-left: 18px; color: var(--ink-2); font-size: 14px; }
.cols li { margin-bottom: 6px; }

/* ---------------------------------------------------------- misc */
.empty { padding: 60px 0; color: var(--ink-3); text-align: center; }
.empty h3 { font-size: 16px; color: var(--ink-2); margin-bottom: 6px; }
.toast {
  position: fixed; left: 50%; bottom: 26px; transform: translate(-50%, 14px);
  background: #241f19; color: #f7f1e6; padding: 10px 16px; border-radius: 10px;
  font-size: 13.5px; opacity: 0; pointer-events: none; transition: opacity .2s ease, transform .2s ease;
  z-index: 60; max-width: 84vw;
}
.toast.on { opacity: 1; transform: translate(-50%, 0); }
.result { display: grid; gap: 26px; }
.result .score { font-family: var(--kai); font-size: 60px; line-height: 1; color: var(--red); }
.result .score small { font-size: 18px; color: var(--ink-3); font-family: var(--sans); margin-left: 6px; }
.review-list { display: grid; gap: 12px; }
.review { border-top: var(--rule); padding: 12px 0; display: grid; gap: 6px; }
.review .s { font-size: 14.5px; line-height: 1.7; }
.review .a { font-size: 13px; color: var(--ink-2); }
.review .a b { color: var(--green); }
.review .a s { color: var(--red); text-decoration-thickness: 1px; }

@media (max-width: 1180px) {
  .quiz-wrap { grid-template-columns: minmax(0, 1fr); }
  .quiz-aside { position: static; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
  .mind-shell { grid-template-columns: minmax(0, 1fr); }
  .drawer { height: auto; min-height: 0; border-top: var(--rule); }
  .mind-canvas { height: 60vh; }
  .subj-wrap { grid-template-columns: 1fr; }
  .subj-list { max-height: 300px; }
}
@media (max-width: 900px) {
  .shell { grid-template-columns: 1fr; }
  .rail { position: static; height: auto; border-right: 0; border-bottom: var(--rule); overflow: hidden; }
  .rail-nav {
    display: flex; grid-auto-flow: unset;
    overflow-x: auto; gap: 4px; width: 100%; padding-bottom: 5px;
    -webkit-overflow-scrolling: touch;
  }
  .nav-item { flex: 0 0 auto; white-space: nowrap; }
  .nav-item em { margin-left: 6px; }
  body { font-size: 16px; }                     /* 手机上正文不小于 16px */
  .rail-note, .rail-foot { display: none; }
  .main {
    padding: 22px max(18px, env(safe-area-inset-left)) 96px max(18px, env(safe-area-inset-right));
  }
  .board { grid-template-columns: 1fr; gap: 20px; }
  .seg { flex-wrap: wrap; }
  .qbar { gap: 8px; }
  .subj-reader .q { font-size: 19px; }
  /* 主操作留在拇指区：翻页/判分按钮贴在底部 */
  .quiz-main .action-row.primary {
    position: sticky; bottom: calc(64px + env(safe-area-inset-bottom));
    background: var(--paper-2);
    border-top: var(--rule);
    box-shadow: 0 -10px 20px -16px rgba(60, 45, 25, .6);
    padding: 10px 0 8px; margin-top: 14px; z-index: 6; flex-wrap: nowrap;
  }
  .quiz-main .action-row.primary .btn { flex: 1 1 auto; white-space: nowrap; }
  .only-wide { display: none; }
  /* 题目信息条随滚动停在顶部，长选择题不至于失去上下文 */
  .quiz-main > .qbar:first-of-type {
    position: sticky; top: 0; z-index: 6;
    background: var(--paper); padding: 8px 0; margin-bottom: 8px;
  }
  /* 手机端把标题区压扁：重复进来的人不需要每次读那段说明 */
  .page-head { margin-bottom: 14px; gap: 2px; }
  .page-head h1 { font-size: 22px; }
  .page-head .sub { display: none; }
  .page-head .rule { display: none; }
  /* 18 个章节改成单行横向滚动，省出竖向空间 */
  .chapter-tabs { flex-wrap: nowrap; overflow-x: auto; padding-bottom: 6px; margin-bottom: 10px; }
  .chapter-tabs .tab { flex: 0 0 auto; }
  /* 手指点得到 */
  @media (pointer: coarse) {
    .tab, .chip, .mark-btn, .ghost-btn, .point-open, .related button { min-height: 40px; padding-top: 8px; padding-bottom: 8px; }
    .opt { padding: 14px 16px; }
  }
}
@media (min-width: 1100px) {
  .modules { grid-template-columns: 1fr 1fr; column-gap: 40px; }   /* 首页模块两列，少滚一半 */
}

/* ---------------------------------------------------------- 数据看板 */
.strip {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  border-top: var(--rule); border-bottom: var(--rule); margin-bottom: 34px;
}
.strip-item { padding: 16px 14px 16px 0; display: grid; gap: 2px; }
.strip-item + .strip-item { border-left: var(--rule); padding-left: 16px; }
.strip-item em { font-style: normal; font-size: 25px; font-weight: 650; font-variant-numeric: tabular-nums; letter-spacing: -0.02em; }
.strip-item span { font-size: 12.5px; color: var(--ink-3); }
.stat-block { margin-bottom: 34px; }
.stat-block h2 { font-family: var(--kai); font-size: 21px; margin-bottom: 14px; }
.stat-table { display: grid; }
.stat-row {
  display: grid; grid-template-columns: minmax(150px, 1.4fr) auto;
  gap: 6px 14px; align-items: center; padding: 10px 0; border-bottom: var(--rule);
}
.stat-row .name { font-size: 14px; color: var(--ink); }
.stat-row .num { font-size: 12.5px; color: var(--ink-2); font-variant-numeric: tabular-nums; }
.stat-row .track { grid-column: 1 / -1; height: 6px; }
.stat-row .track i { background: var(--red-2); }
.stat-row .track i.ok { background: #6d9a80; }
.stat-row.wide { grid-template-columns: minmax(150px, 1.6fr) auto auto; }
.stat-row.wide .track { grid-column: 1 / -1; }
.chart { width: 100%; height: auto; max-width: 660px; }
@media (min-width: 1240px) {
  body.ai-open .shell { padding-right: min(430px, 34vw); }
}
.chip {
  border: var(--rule); background: var(--paper-2); border-radius: 99px;
  padding: 4px 11px; font-size: 12.5px; color: var(--ink-2); cursor: pointer;
}
.chip:hover { border-color: var(--red-2); color: var(--red); background: var(--red-tint); }
.sync-box { display: grid; gap: 10px; border: var(--rule); border-radius: var(--radius); background: var(--paper-2); padding: 16px; }
.sync-box textarea {
  width: 100%; border: var(--rule); border-radius: var(--radius-sm); padding: 10px;
  font: inherit; font-size: 13px; resize: vertical; background: var(--paper); color: var(--ink);
}
.sync-box textarea::placeholder { color: var(--ink-3); }

/* ---------------------------------------------------------- AI 助教 */
.ai-open-btn { color: var(--red); border-color: var(--red-2); background: var(--red-tint); font-weight: 600; }
.ai-panel {
  position: fixed; top: 0; right: 0; bottom: 0; width: min(430px, 100vw);
  background: var(--paper-2); border-left: var(--rule);
  display: flex; flex-direction: column;
  transform: translateX(102%); transition: transform .28s cubic-bezier(.2,.8,.25,1);
  z-index: 70; box-shadow: -18px 0 44px -30px rgba(50,35,15,.55);
}
.ai-panel > * { flex: 0 0 auto; }
.ai-panel.on { transform: none; }
.ai-head { display: flex; align-items: center; gap: 8px; padding: 14px 16px; border-bottom: var(--rule); }
.ai-head .spacer { flex: 1; }
.ai-head strong { font-family: var(--kai); font-size: 18px; }
.ai-cfg { padding: 14px 16px; border-bottom: var(--rule); display: grid; gap: 10px; background: var(--paper); }
.ai-cfg[hidden] { display: none; }
.ai-cfg label { display: grid; gap: 4px; font-size: 12px; color: var(--ink-3); }
.ai-cfg .row { display: flex; align-items: center; gap: 10px; }
.ai-note { font-size: 11.5px; color: var(--ink-3); line-height: 1.5; }
.ai-body { flex: 1 1 auto; min-height: 0; overflow: auto; padding: 16px; display: grid; gap: 12px; align-content: start; }
.ai-msg { border-radius: var(--radius); padding: 11px 13px; font-size: 14px; line-height: 1.75; }
.ai-msg p { margin: 0; }
.ai-msg.sys { background: var(--paper-3); color: var(--ink-2); font-size: 13px; white-space: pre-line; }
.ai-msg.user { background: var(--red-tint); color: #6d1a10; justify-self: end; max-width: 92%; }
.ai-msg.ai { background: var(--paper); border: var(--rule); }
.ai-msg.ai b { color: var(--red); }
.ai-msg.ai em { color: var(--ink-3); font-style: normal; font-size: 12.5px; }
.ai-chips { display: flex; gap: 6px; overflow-x: auto; padding: 10px 16px; border-top: var(--rule); }
.ai-chips .chip { white-space: nowrap; flex: 0 0 auto; }
.ai-input { display: flex; gap: 8px; padding: 12px 16px calc(12px + env(safe-area-inset-bottom)); border-top: var(--rule); }
.ai-input input { flex: 1; }

/* ---------------------------------------------------------- 手机底栏 */
.quiz-hud {
  display: flex; gap: var(--s2); align-items: center; justify-content: flex-end;
  flex-wrap: wrap; margin-bottom: var(--s3);
}
.hud-item {
  font-size: 12.5px; color: var(--ink-2); background: var(--paper-3);
  border-radius: 99px; padding: 4px 10px; font-variant-numeric: tabular-nums;
}
.hud-item.ok { background: var(--green-tint); color: var(--green); }
.hud-item.no { background: var(--red-tint); color: var(--red); }
.hud-item.hud-time {
  border: var(--rule); background: var(--paper-2); color: var(--ink-2);
  cursor: pointer; font-weight: 600;
}
.hud-item.hud-time:hover { border-color: var(--red-2); color: var(--red); background: var(--red-tint); }
.hud-hand { border: var(--rule); background: var(--paper-2); color: var(--ink-2); cursor: pointer; }
.hud-hand:hover { border-color: var(--red-2); color: var(--red); }

/* 排除法：长按选项划掉 */
.opt-row { display: flex; gap: 8px; align-items: stretch; }
.opt-row .opt { flex: 1 1 auto; min-width: 0; }
.opt, .opt-row { -webkit-touch-callout: none; -webkit-user-select: none; user-select: none; }
.opt-ex {
  flex: none; width: 56px; border: var(--rule); border-radius: var(--radius-sm);
  background: var(--paper-3); color: var(--ink-3); font-size: 12px; cursor: pointer;
  transition: background .15s ease, color .15s ease, border-color .15s ease;
}
.opt-ex:hover { border-color: var(--line-2); color: var(--ink-2); }
.opt-ex.on { background: var(--red-tint); border-color: #d9a99f; color: var(--red); font-weight: 600; }
@media (max-width: 900px) { .opt-ex { width: 62px; } }
.opt.excluded {
  opacity: .5; background: var(--paper-3); border-style: dashed;
}
.opt.excluded > span:not(.key) { text-decoration: line-through; text-decoration-thickness: 1.5px; }
.opt.excluded .key { background: var(--line-2); color: var(--paper-2); }

/* 出处条：放在选项下面 */
.src-row { margin: 14px 0 0; padding-top: 12px; border-top: var(--rule); }
.src-row .pill { font-size: 12px; }

/* 本次练习面板（点计时打开） */
.sess-backdrop {
  position: fixed; inset: 0; z-index: 90; display: none;
  align-items: flex-end; justify-content: center;
  background: color-mix(in srgb, var(--ink) 34%, transparent);
  backdrop-filter: blur(2px);
}
.sess-backdrop.on { display: flex; }
.sess-panel {
  background: var(--paper-2); width: min(520px, 100%);
  border-radius: 16px 16px 0 0; padding: 18px 18px calc(18px + env(safe-area-inset-bottom));
  box-shadow: 0 -18px 44px -26px rgba(40, 28, 12, .6);
  display: grid; gap: 14px; max-height: 88vh; overflow: auto;
}
@media (min-width: 901px) {
  .sess-backdrop { align-items: center; }
  .sess-panel { border-radius: var(--radius); }
}
.sess-head { display: flex; align-items: center; justify-content: space-between; }
.sess-head strong { font-family: var(--kai); font-size: 19px; }
.sess-acts { display: grid; gap: 8px; }
.sess-acts .btn { width: 100%; }
.sess-toggles { display: flex; gap: 8px; flex-wrap: wrap; }
.chip.on { background: var(--green-tint); border-color: #a9c4b3; color: var(--green); font-weight: 600; }

/* 模拟考试：AI 评分状态条 */
.ver-foot {
  margin-top: 34px; border-top: var(--rule); padding-top: 16px;
  display: grid; gap: 4px; color: var(--ink-3);
}
.ver-foot p { margin: 0; font-size: 13px; }
.ver-foot b { color: var(--red); font-size: 15px; letter-spacing: .02em; }
.mock-ai-state {
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  border: var(--rule); border-radius: var(--radius-sm);
  background: var(--paper-2); padding: 11px 13px; margin: 14px 0 4px;
  font-size: 14px; color: var(--ink-2);
}
.mock-ai-state b { color: var(--ink); }
.mock-ai-state span { font-size: 13px; color: var(--ink-3); }
.mock-ai-state.ok { border-left: 3px solid var(--green); }
.mock-ai-state.ok .tick { color: var(--green); font-size: 13px; }
.mock-ai-state.warn { border-left: 3px solid var(--gold); background: var(--gold-tint); }
.mock-ai-state.warn b { color: var(--gold); }
.mock-ai-state .btn { margin-left: auto; }

/* 考点对话框 */
.sheet-backdrop {
  position: fixed; inset: 0; background: rgba(30, 24, 18, .38);
  display: none; align-items: center; justify-content: center; z-index: 90; padding: 20px;
}
.sheet-backdrop.on { display: flex; }
body.sheet-open { overflow: hidden; }
.sheet {
  background: var(--paper-2); border-radius: var(--radius); width: min(560px, 100%);
  max-height: min(78vh, 720px); display: flex; flex-direction: column;
  box-shadow: 0 24px 60px -24px rgba(40, 28, 12, .55);
}
.sheet-head {
  display: flex; align-items: center; gap: var(--s3);
  padding: var(--s4) var(--s4) var(--s3); border-bottom: var(--rule);
}
.sheet-head strong { font-family: var(--kai); font-size: 18px; line-height: 1.45; }
.sheet-head .ghost-btn { margin-left: auto; flex: none; }
.sheet-body { overflow: auto; padding: var(--s4); }
.sheet-path { font-size: 12.5px; color: var(--ink-3); margin-bottom: var(--s3); }
.sheet-label { font-size: 12px; letter-spacing: .06em; color: var(--ink-3); margin: var(--s4) 0 var(--s2); }
.sheet-tools { display: grid; gap: var(--s2); margin-top: var(--s4); }
.sheet-tools .btn { width: 100%; }
.sheet-kids { display: grid; gap: 6px; }
.sheet-kid {
  display: flex; align-items: center; gap: 10px; width: 100%; text-align: left;
  background: var(--paper-2); border: var(--rule); border-radius: var(--radius-sm);
  padding: 12px 13px; font-size: 14.5px; line-height: 1.6; color: var(--ink); cursor: pointer;
}
.sheet-kid:hover { border-color: var(--red-2); background: var(--red-tint); color: var(--red); }
.sheet-kid .sk-text { flex: 1; }
.sheet-kid .sk-n { flex: none; font-size: 11.5px; color: var(--ink-3); background: var(--paper-3); border-radius: 99px; padding: 2px 8px; }
.sheet-head { flex-wrap: wrap; }
.sheet-back { order: -1; }

/* 大纲视图 */
.mind-canvas.outline-mode {
  height: auto; min-height: 0; overflow: visible;
  background: var(--paper); border-right: 0; padding: 0 0 var(--s4);
}
.outline-tree { display: grid; }
.ol-row {
  display: flex; align-items: center; gap: var(--s2);
  padding-left: calc(var(--d) * 16px);
  border-bottom: var(--rule);
}
.ol-caret {
  flex: none; width: 30px; height: 30px; border-radius: 8px; cursor: pointer;
  border: var(--rule); background: var(--paper-2); color: var(--ink-3);
  font-size: 15px; line-height: 1;
}
.ol-caret.open { background: var(--red-tint); border-color: var(--red-2); color: var(--red); }
.ol-dot {
  flex: none; width: 30px; display: grid; place-items: center; color: var(--line-2);
}
.ol-dot::before { content: ""; width: 6px; height: 6px; border-radius: 99px; background: currentColor; }
.ol-text {
  flex: 1; text-align: left; background: none; border: 0; cursor: pointer;
  padding: 11px 4px; font-size: 14.5px; line-height: 1.6; color: var(--ink);
  display: flex; align-items: baseline; gap: var(--s2);
}
.ol-text.branch { font-weight: 600; }
.ol-text.root { font-family: var(--kai); font-size: 17px; }
.ol-text:hover { color: var(--red); }
.ol-text.hit { color: var(--red); }
.ol-badge {
  flex: none; font-size: 11px; font-weight: 500; color: var(--ink-3);
  background: var(--paper-3); border-radius: 99px; padding: 1px 7px;
}
.ol-row.dimmed { opacity: .45; }
.ol-more {
  flex: none; border: var(--rule); background: var(--paper-2); color: var(--ink-3);
  border-radius: 99px; padding: 5px 10px; font-size: 12px; cursor: pointer;
}
.ol-more:hover { border-color: var(--red-2); color: var(--red); background: var(--red-tint); }
.hud-star.on, .hud-sound.on { background: var(--gold-tint); color: var(--gold); border-color: #e0cd9f; }
.hud-star .hud-word, .hud-sound .hud-word { margin-left: 4px; }
@media (max-width: 900px) {
  .hud-star .hud-word { display: none; }        /* 手机上只留图标，省地方 */
}
.mind-tip { margin-top: var(--s3); }

/* 右手 / 左手模式：主操作按钮靠拇指这一侧 */
/* ---------------------------------------------------------- 试用 / 兑换码 */
/* 工具分组（默认收起） */
.nav-sub { display: none; margin-left: 10px; border-left: 2px solid var(--line); padding-left: 6px; }
body.tools-open .nav-sub { display: grid; gap: 2px; }
.nav-group .nav-caret { margin-left: auto; font-style: normal; font-size: 11px; color: var(--ink-3); }
body.tools-open .nav-group .nav-caret { transform: rotate(180deg); }

/* 顶部两端：左边返回，右边刷新 */
.rail-top { display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: start; gap: 6px; }
.nav-icon-btn {
  width: 40px; height: 40px; flex: none;
  display: grid; place-items: center;
  border: var(--rule); border-radius: 10px;
  background: var(--paper-2); color: var(--ink-2); cursor: pointer;
  transition: background .15s ease, color .15s ease, border-color .15s ease;
}
.nav-icon-btn:hover { border-color: var(--red-2); color: var(--red); background: var(--red-tint); }
.nav-icon-btn .nav-ico, .nav-icon-btn .nav-ico svg { width: 19px; height: 19px; }
#refresh-btn { color: var(--red); }
#refresh-btn:active .nav-ico { transform: rotate(-90deg); transition: transform .18s ease; }
@media (min-width: 901px) {
  .rail-top { grid-template-columns: 1fr auto; grid-template-areas: "back refresh" "nav nav"; row-gap: 10px; }
  #back-btn { grid-area: back; justify-self: start; }
  #refresh-btn { grid-area: refresh; justify-self: end; }
  .rail-top .rail-nav { grid-area: nav; }
}

/* 学习台底部提示（替代原来的卡片堆） */
.home-tips { margin-top: 30px; border-top: var(--rule); padding-top: 18px; display: grid; gap: 8px; }
.home-tips p { font-size: 14px; color: var(--ink-2); line-height: 1.8; margin: 0; }
.home-tips b { color: var(--ink); }

/* 背题模块 */
.bc-card { border-top: var(--rule); padding-top: 18px; }
.bc-stem { font-size: 17px; line-height: 1.8; margin-bottom: 14px; max-width: min(72ch, 100%); }
.bc-opt { cursor: default; }
.bc-opt.correct { border-color: #9fbcaa; background: var(--green-tint); }
.bc-opt.correct .key { background: var(--green); color: #fff; }
.bc-opt:hover { background: inherit; }

/* 真题训练 */
.paper-list { display: grid; }
.paper { border-bottom: var(--rule); padding: 16px 0; }
.paper.pending { opacity: .72; }
.paper-head { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.paper-head strong { font-size: 16px; }
.paper .explain { margin: 6px 0 0; }

/* 模拟考试 */
.mock-last { border: var(--rule); border-left: 3px solid var(--red); border-radius: var(--radius-sm);
  background: var(--paper-2); padding: 12px 14px; margin-bottom: 18px; font-size: 14.5px; color: var(--ink-2); }
.mock-last b { color: var(--ink); }
.mock-hud { position: sticky; top: 0; z-index: 7; display: flex; align-items: center; gap: 8px; flex-wrap: wrap;
  background: var(--paper); padding: 8px 0 10px; margin-bottom: 6px; border-bottom: var(--rule); }
.mock-hud .pill.red { font-variant-numeric: tabular-nums; }
.mock-hud .btn { margin-left: auto; }
.mock-card { border: var(--rule); border-radius: var(--radius); background: var(--paper-2); padding: 18px 18px 8px; }
.mock-card .bc-stem { margin-bottom: 12px; }
.mock-card .opts { margin-bottom: 12px; }
.mock-input { width: 100%; resize: vertical; min-height: 132px; padding: 11px 13px; line-height: 1.8;
  border: var(--rule); border-radius: var(--radius-sm); background: var(--paper-2); font-size: 15px; }
.mock-input:focus { outline: 2px solid var(--red-2); outline-offset: 1px; }
.mock-nav { display: grid; grid-template-columns: repeat(auto-fill, minmax(42px, 1fr)); gap: 6px; margin-top: 16px; }
.mock-cell { border: var(--rule); background: var(--paper-2); border-radius: var(--radius-sm);
  padding: 7px 0; font-size: 13px; color: var(--ink-2); cursor: pointer; font-variant-numeric: tabular-nums; }
.mock-cell:hover { border-color: var(--red-2); color: var(--red); }
.mock-cell.done { background: var(--green-tint); border-color: #a9c4b3; color: var(--green); font-weight: 600; }
.mock-cell.cur { background: var(--red); border-color: var(--red); color: #fff; font-weight: 700; }
.mock-score { border-bottom: var(--rule); padding-bottom: 18px; margin-bottom: 6px; }
.mock-score .score { font-family: var(--kai); font-size: 58px; line-height: 1.1; color: var(--red); }
.mock-score .score small { font-size: 17px; color: var(--ink-3); font-family: var(--sans); margin-left: 8px; }
.mock-score .explain { margin: 6px 0 0; }
.mock-review { display: grid; }
.mock-review .review { border-bottom: var(--rule); padding: 16px 0; }
.mock-review .review .qbar { margin-bottom: 8px; }
.mock-review .review .s { font-size: 15px; line-height: 1.75; }
.mock-review .review .a { font-size: 13.5px; color: var(--ink-2); line-height: 1.8; }
@media (max-width: 900px) {
  .mock-hud .btn { margin-left: 0; flex: 1 1 100%; }
  .mock-nav { grid-template-columns: repeat(auto-fill, minmax(38px, 1fr)); }
  .mock-score .score { font-size: 46px; }
}

/* 底部常驻操作条：未作答时是「直接看答案 + 收藏」，作答后是「上一题 / 下一题 / 收藏」 */
.quiz-main .action-row.sticky-actions { position: static; }
@media (max-width: 900px) {
  .quiz-main { padding-bottom: 86px; }
  .quiz-main .action-row.sticky-actions {
    position: fixed; left: 0; right: 0;
    bottom: calc(58px + env(safe-area-inset-bottom));
    background: var(--paper-2); border-top: var(--rule);
    box-shadow: 0 -10px 20px -16px rgba(60, 45, 25, .55);
    padding: 8px 14px; margin: 0; z-index: 8;
    display: flex; gap: 8px; flex-wrap: nowrap;
  }
  .quiz-main .action-row.sticky-actions .btn { flex: 1 1 auto; white-space: nowrap; }
  .quiz-main .action-row.sticky-actions .pill { display: none; }   /* 提示不占位 */
  /* 设置区落在固定操作条下方时，留出空间别被压住 */
  .filters { margin-bottom: 64px; }
}
.gate-badge {
  position: fixed; right: 12px; bottom: 12px; z-index: 80;
  display: flex; align-items: center; gap: 6px;
  font-size: 11.5px; color: var(--ink-2);
  background: color-mix(in srgb, var(--paper-2) 92%, transparent);
  border: var(--rule); border-radius: 99px; padding: 5px 11px;
  backdrop-filter: blur(4px); max-width: 70vw;
}
.gate-badge .gb-dot { width: 7px; height: 7px; border-radius: 99px; background: var(--gold); flex: none; }
.gate-badge.ok .gb-dot { background: var(--green); }
.gate-badge.trial .gb-dot { background: var(--red-2); }
.gate-badge b { color: var(--red); font-variant-numeric: tabular-nums; }
.gate-wall {
  position: fixed; inset: 0; z-index: 95; display: none;
  align-items: center; justify-content: center; padding: 20px;
  background: color-mix(in srgb, var(--paper) 86%, transparent);
  backdrop-filter: blur(6px);
}
.gate-wall.on { display: flex; }
.gate-card {
  background: var(--paper-2); border: var(--rule); border-radius: var(--radius);
  padding: 26px 24px; width: min(460px, 100%);
  box-shadow: 0 26px 60px -30px rgba(40, 28, 12, .5);
}
.gate-card h2 { font-family: var(--kai); font-size: 24px; margin-bottom: 8px; }
.gate-sub { font-size: 14px; color: var(--ink-2); line-height: 1.75; margin-bottom: 16px; }
.gate-row { display: flex; gap: 8px; }
.gate-row input {
  flex: 1; min-width: 0; letter-spacing: .06em; text-transform: uppercase;
  font-variant-numeric: tabular-nums;
}
.gate-msg { font-size: 13px; margin-top: 10px; min-height: 18px; color: var(--ink-2); }
.gate-msg.no { color: var(--red); }
.gate-msg.ok { color: var(--green); }
.gate-note { font-size: 12px; color: var(--ink-3); margin-top: 12px; line-height: 1.7; }
body.gate-locked .main, body.gate-locked .rail { filter: blur(1.5px); }
@media (max-width: 900px) {
  .gate-badge { bottom: calc(74px + env(safe-area-inset-bottom)); font-size: 11px; }
}

@media (max-width: 900px) {
  .quiz-main .action-row.primary { justify-content: flex-end; }
  body.hand-left .quiz-main .action-row.primary { justify-content: flex-start; flex-direction: row-reverse; }
  .card .row { justify-content: flex-end; }
  body.hand-left .card .row { justify-content: flex-start; }
  .quiz-hud { position: sticky; top: 0; z-index: 7; background: var(--paper); padding: 6px 0; margin-bottom: var(--s2); }
  .quiz-main > .qbar:first-of-type { top: 44px; }
  .sheet-backdrop { align-items: flex-end; padding: 0; }
  .sheet {
    width: 100%; max-height: 84vh; border-radius: 16px 16px 0 0;
    padding-bottom: env(safe-area-inset-bottom);
  }
}
@media (min-width: 901px) {
  body.hand-left .quiz-main .action-row { flex-direction: row-reverse; justify-content: flex-end; }
}

.tabbar { display: none; }
@media (max-width: 900px) {
  .tabbar {
    display: grid; grid-auto-flow: column; grid-auto-columns: 1fr;
    position: fixed; left: 0; right: 0; bottom: 0; z-index: 50;
    background: color-mix(in srgb, var(--paper-2) 94%, transparent);
    backdrop-filter: blur(6px);
    border-top: var(--rule); padding: 6px 4px calc(6px + env(safe-area-inset-bottom));
  }
  .tabbar-item {
    background: none; border: 0; cursor: pointer; color: var(--ink-3);
    display: grid; justify-items: center; gap: 2px; padding: 4px 2px; font-size: 10.5px;
    border-radius: 9px;
  }
  .tabbar-item .nav-ico, .tabbar-item .nav-ico svg { width: 21px; height: 21px; }
  .tabbar-item[aria-current="page"] { color: var(--red); }
  .tabbar-item-ai { color: var(--red); }
  .main { padding-bottom: 96px; }
  body.ai-open .ai-panel {
    top: auto; left: 0; right: 0; width: auto;
    height: min(80vh, 620px);
    bottom: calc(56px + env(safe-area-inset-bottom));
    border-left: 0; border-top: var(--rule); border-radius: 16px 16px 0 0;
    transform: translateY(102%);
  }
  body.ai-open .ai-panel.on { transform: none; }
  .ai-panel { box-shadow: 0 -18px 44px -30px rgba(50,35,15,.55); }
  .ai-head::before {
    content: ""; position: absolute; top: 6px; left: 50%; transform: translateX(-50%);
    width: 40px; height: 4px; border-radius: 99px; background: var(--line-2);
  }
  .ai-head { position: relative; padding-top: 18px; }
  .tabbar { z-index: 80; }
  .mind-canvas { height: 58vh; min-height: 380px; }
  .drawer { border-top: var(--rule); }
  .stat-row { grid-template-columns: minmax(0, 1fr) auto; }
  .strip-item em { font-size: 21px; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .001ms !important; transition-duration: .001ms !important; }
}

/* 手机端：工具子项不要挤在「错题本 / 工具」右边，改成整行的胶囊条 */
@media (max-width: 900px) {
  .rail-nav { flex-wrap: wrap; }
  body.tools-open .nav-sub {
    flex: 1 1 100%;
    grid-auto-flow: column; grid-auto-columns: max-content;
    overflow-x: auto; gap: 6px;
    margin: 6px 0 0; padding: 0 0 4px; border-left: 0;
  }
  .nav-sub .nav-item { border: var(--rule); border-radius: 99px; background: var(--paper-2); padding: 7px 11px; }
  .nav-sub .nav-item[aria-current="page"] { border-color: var(--red-2); }
}