/* =========================================================
   史鉴 · 历史课堂教学台
   Design tokens
   ========================================================= */
:root{
  --paper:#f5f1e8;
  --paper-2:#fffdf7;
  --paper-3:#ece5d7;
  --ink:#1a1d23;
  --ink-2:#454b56;
  --ink-3:#83878d;
  --line:rgba(26,29,35,.10);
  --line-2:rgba(26,29,35,.16);
  --cinnabar:#b0392d;
  --cinnabar-2:#c9543f;
  --cinnabar-soft:rgba(176,57,45,.09);
  --gold:#a5843f;
  --gold-soft:rgba(165,132,63,.12);
  --jade:#38685a;
  --jade-soft:rgba(56,104,90,.10);
  --indigo:#3a4a6b;
  --indigo-soft:rgba(58,74,107,.10);
  --rail:#15181e;
  --rail-2:#1e232b;
  --radius:16px;
  --radius-sm:10px;
  --shadow-sm:0 1px 2px rgba(26,29,35,.05);
  --shadow-md:0 22px 48px -30px rgba(26,29,35,.5);
  --serif:"Source Han Serif SC","Noto Serif SC","STZhongsong","Songti SC","SimSun",serif;
  --sans:"PingFang SC","Noto Sans SC","Microsoft YaHei","Hiragino Sans GB",system-ui,-apple-system,sans-serif;
  --mono:"SF Mono","JetBrains Mono","Consolas",ui-monospace,monospace;
}

*,*::before,*::after{box-sizing:border-box}
html,body{margin:0;padding:0}
body{
  font-family:var(--sans);
  color:var(--ink);
  background:var(--paper);
  -webkit-font-smoothing:antialiased;
  font-size:14.5px;
  line-height:1.65;
  min-height:100vh;
}
body::before{
  content:"";position:fixed;inset:0;z-index:0;pointer-events:none;
  background-image:radial-gradient(circle at 12% 8%,rgba(165,132,63,.10),transparent 42%),
                   radial-gradient(circle at 88% 0%,rgba(176,57,45,.06),transparent 38%);
}
body.presenting{overflow:hidden}
::selection{background:rgba(176,57,45,.18)}
button{font-family:inherit;cursor:pointer;border:0;background:none;color:inherit}
input,select,textarea{font-family:inherit;font-size:14px;color:var(--ink)}
h1,h2,h3,h4,p{margin:0}
b,strong{font-weight:600}
svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.6;stroke-linecap:round;stroke-linejoin:round}

/* =========================================================
   Layout
   ========================================================= */
.app{
  position:relative;z-index:1;
  display:grid;grid-template-columns:92px minmax(0,1fr);
  min-height:100vh;
}

/* ---------- Rail ---------- */
.rail{
  position:sticky;top:0;height:100vh;
  background:
    radial-gradient(120% 60% at 50% 0%,#252b35 0%,transparent 60%),
    var(--rail);
  display:flex;flex-direction:column;align-items:center;
  padding:20px 0 16px;
  border-right:1px solid rgba(255,255,255,.06);overflow-y:auto;scrollbar-width:none;
}
.rail::-webkit-scrollbar{display:none}
.brand{display:flex;flex-direction:column;align-items:center;gap:8px;margin-bottom:26px}
.brand-mark{
  width:42px;height:42px;border-radius:9px;
  background:#f7f0e3;object-fit:cover;object-position:center 23%;display:block;
  box-shadow:0 6px 16px -6px rgba(176,57,45,.75), inset 0 0 0 1px rgba(255,255,255,.15);
}
.brand-sub{
  font-size:10.5px;letter-spacing:.32em;color:rgba(255,255,255,.42);
  writing-mode:horizontal-tb;text-indent:.32em;
}
.rail-nav{display:flex;flex-direction:column;gap:4px;width:100%;align-items:center}
.rail-btn{
  width:64px;padding:10px 0 8px;border-radius:10px;
  display:flex;flex-direction:column;align-items:center;gap:5px;
  color:rgba(255,255,255,.48);
  transition:background .18s ease,color .18s ease,transform .18s ease;
  position:relative;
}
.rail-btn svg{width:19px;height:19px}
.rail-btn span{font-size:10.5px;letter-spacing:.12em}
.rail-btn:hover{color:rgba(255,255,255,.86);background:rgba(255,255,255,.05)}
.rail-btn.is-active{color:#fff;background:rgba(255,255,255,.08)}
.rail-btn.is-active::before{
  content:"";position:absolute;left:-14px;top:50%;transform:translateY(-50%);
  width:3px;height:22px;border-radius:3px;background:var(--cinnabar-2);
  box-shadow:0 0 12px rgba(201,84,63,.8);
}
.rail-btn.is-active svg{color:#f0c9a0}
.rail-foot{margin-top:auto;width:100%;display:flex;justify-content:center}

/* ---------- Main ---------- */
.main{min-width:0;padding:0 40px 72px;max-width:1420px;margin:0 auto;width:100%}

.topbar{
  position:sticky;top:0;z-index:30;
  display:flex;align-items:center;justify-content:space-between;gap:24px;
  padding:18px 0 16px;
  background:rgba(245,241,232,.93);
  backdrop-filter:blur(10px) saturate(1.1);
  border-bottom:1px solid var(--line);
}
.eyebrow{
  font-size:10.5px;letter-spacing:.26em;text-transform:uppercase;
  color:var(--ink-3);font-weight:500;
}
.eyebrow-rule{display:flex;align-items:center;gap:10px;color:var(--cinnabar)}
.eyebrow-rule::before{content:"";width:18px;height:1px;background:var(--cinnabar);opacity:.65}
.topbar-course .eyebrow{font-family:var(--serif);font-size:12px;letter-spacing:.18em;color:var(--ink-2);text-transform:none}
.course-meta{display:flex;align-items:center;gap:9px;margin-top:3px;font-size:12px;color:var(--ink-3)}
.course-meta .dot{width:3px;height:3px;border-radius:50%;background:var(--ink-3);opacity:.6}

.topbar-actions{display:flex;align-items:center;gap:12px}
.clock{text-align:right;padding-right:6px;border-right:1px solid var(--line);margin-right:2px}
.clock-time{font-family:var(--mono);font-size:17px;letter-spacing:.04em;font-weight:500;line-height:1.1;font-variant-numeric:tabular-nums}
.clock-date{font-size:10.5px;color:var(--ink-3);letter-spacing:.06em}

/* =========================================================
   Buttons / inputs / chips
   ========================================================= */
.btn{
  display:inline-flex;align-items:center;gap:7px;
  height:38px;padding:0 16px;border-radius:var(--radius-sm);
  border:1px solid var(--line-2);background:rgba(255,253,247,.7);
  font-size:13px;letter-spacing:.04em;color:var(--ink);
  transition:all .18s ease;white-space:nowrap;
}
.btn:hover{border-color:rgba(26,29,35,.32);background:#fffdf7;transform:translateY(-1px);box-shadow:var(--shadow-sm)}
.btn:active{transform:translateY(0)}
.btn-primary{background:var(--ink);border-color:var(--ink);color:#f7f1e4}
.btn-primary:hover{background:#2a2f38;border-color:#2a2f38;color:#fff}
.btn-cinnabar{background:var(--cinnabar);border-color:var(--cinnabar);color:#fdf6ea}
.btn-cinnabar:hover{background:#c0453a;border-color:#c0453a;color:#fff}
.btn-plus{font-size:15px;line-height:1;margin-top:-1px}
.btn-ico{width:14px;height:14px}
.link-btn{font-size:12.5px;color:var(--ink-3);letter-spacing:.04em;transition:color .16s}
.link-btn:hover{color:var(--cinnabar)}
.head-actions{display:flex;gap:10px;flex-wrap:wrap}

.input,select,textarea{
  height:38px;padding:0 12px;border-radius:var(--radius-sm);
  border:1px solid var(--line);background:#fffdf7;
  outline:none;transition:border-color .16s,box-shadow .16s;
  min-width:0;
}
select{
  appearance:none;padding-right:30px;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%2383878d' stroke-width='2.2' stroke-linecap='round'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");
  background-repeat:no-repeat;background-position:right 11px center;
  cursor:pointer;
}
.input:focus,select:focus,textarea:focus{border-color:var(--cinnabar);box-shadow:0 0 0 3px rgba(176,57,45,.10)}
.input-lg{height:42px;font-family:var(--serif);font-size:17px;letter-spacing:.02em}
textarea{height:auto;padding:10px 12px;resize:vertical;line-height:1.7}
.field-label{display:block;font-size:11px;letter-spacing:.16em;color:var(--ink-3);margin-bottom:6px;text-transform:uppercase}

/* =========================================================
   Views / headings
   ========================================================= */
.views{padding-top:18px}
.view{display:none;animation:viewIn .38s cubic-bezier(.22,.7,.3,1)}
.view.is-active{display:block}
@keyframes viewIn{from{opacity:0;transform:translateY(10px)}to{opacity:1;transform:none}}

.page-head{display:flex;align-items:flex-end;justify-content:space-between;gap:24px;padding:26px 0 22px;flex-wrap:wrap}
.page-title{font-family:var(--serif);font-size:34px;letter-spacing:.04em;line-height:1.25;margin-top:8px}
.page-desc{color:var(--ink-3);font-size:13px;margin-top:6px;letter-spacing:.02em}
.page-desc b{color:var(--ink-2)}

.sec-head{display:flex;align-items:flex-end;justify-content:space-between;margin:38px 0 14px;gap:16px}
.sec-head h2{font-family:var(--serif);font-size:21px;letter-spacing:.05em;font-weight:600}
.sec-sub{font-size:12px;color:var(--ink-3);margin-top:3px}

.card{
  background:var(--paper-2);border:1px solid var(--line);
  border-radius:var(--radius);box-shadow:var(--shadow-sm);
}
.card.pad{padding:22px 24px}
.card-head{display:flex;align-items:baseline;justify-content:space-between;gap:12px;margin-bottom:18px}
.card-head h3{font-family:var(--serif);font-size:17px;letter-spacing:.06em;font-weight:600}
.card-hint{font-size:11px;color:var(--ink-3);letter-spacing:.08em}
.grid-2{display:grid;grid-template-columns:1.25fr .9fr;gap:20px;margin-top:24px}

/* =========================================================
   Hero
   ========================================================= */
.hero{
  position:relative;overflow:hidden;
  display:grid;grid-template-columns:minmax(0,1fr) auto;gap:40px;
  padding:38px 42px 40px;
  border-radius:20px;
  border:1px solid var(--line);
  background:
    radial-gradient(120% 140% at 100% 0%,#fbf6e9 0%,transparent 55%),
    linear-gradient(160deg,#fffdf7 0%,#f7f1e3 100%);
  box-shadow:0 30px 60px -46px rgba(26,29,35,.7);
}
.hero::after{
  content:"";position:absolute;inset:0;pointer-events:none;z-index:0;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3'/%3E%3C/filter%3E%3Crect width='140' height='140' filter='url(%23n)' opacity='.5'/%3E%3C/svg%3E");
  opacity:.04;mix-blend-mode:multiply;
}
.hero-watermark{
  position:absolute;right:150px;top:-56px;
  font-family:var(--serif);font-size:300px;line-height:1;color:rgba(26,29,35,.045);
  pointer-events:none;user-select:none;letter-spacing:-.05em;
}
.hero-main{position:relative;z-index:2;max-width:720px}
.hero-title{
  font-family:var(--serif);font-size:clamp(34px,3.1vw,46px);line-height:1.22;
  letter-spacing:.055em;margin:14px 0 0;font-weight:600;
}
.hero-desc{color:var(--ink-2);font-size:14px;line-height:1.9;margin-top:14px;max-width:600px;letter-spacing:.02em}
.hero-actions{display:flex;gap:10px;margin-top:26px;flex-wrap:wrap}
.hero-side{position:relative;z-index:2;display:flex;flex-direction:column;align-items:center;justify-content:space-between;gap:22px}
.hero-seal{
  width:74px;height:74px;border-radius:6px;
  border:1.5px solid rgba(176,57,45,.55);
  display:grid;grid-template-columns:1fr 1fr;place-items:center;
  padding:8px;color:var(--cinnabar);
  font-family:var(--serif);font-size:26px;line-height:1;
  background:rgba(255,253,247,.5);
  box-shadow:inset 0 0 0 3px rgba(176,57,45,.07);
  transform:rotate(-3deg);
}
.hero-facts{display:flex;gap:26px;text-align:center}
.hero-facts div{display:flex;flex-direction:column;gap:2px}
.hero-facts b{font-family:var(--serif);font-size:23px;font-weight:600;letter-spacing:.02em}
.hero-facts em{font-style:normal;font-size:10.5px;color:var(--ink-3);letter-spacing:.14em}

/* =========================================================
   Stats & charts
   ========================================================= */
.stat-row{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-top:20px}
.stat{
  background:var(--paper-2);border:1px solid var(--line);border-radius:var(--radius);
  padding:18px 20px 16px;position:relative;overflow:hidden;
  transition:transform .2s ease,box-shadow .2s ease,border-color .2s;
}
.stat:hover{transform:translateY(-2px);box-shadow:var(--shadow-md);border-color:var(--line-2)}
.stat-top{display:flex;align-items:center;justify-content:space-between}
.stat-label{font-size:11.5px;letter-spacing:.14em;color:var(--ink-3)}
.stat-ico{width:26px;height:26px;border-radius:8px;display:grid;place-items:center}
.stat-ico svg{width:14px;height:14px}
.stat-num{font-family:var(--serif);font-size:36px;line-height:1.15;margin-top:8px;font-weight:600;font-variant-numeric:tabular-nums;letter-spacing:.01em}
.stat-num small{font-size:12px;font-family:var(--sans);color:var(--ink-3);margin-left:5px;letter-spacing:.06em;font-weight:400}
.stat-foot{font-size:11px;color:var(--ink-3);margin-top:4px;letter-spacing:.04em}
.stat-foot b{color:var(--cinnabar);font-weight:600}

.cause-chart{display:flex;flex-direction:column;gap:13px}
.cc-row{display:grid;grid-template-columns:88px 1fr 56px;align-items:center;gap:12px}
.cc-name{font-size:12.5px;color:var(--ink-2);letter-spacing:.04em;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.cc-track{height:9px;border-radius:99px;background:var(--paper-3);overflow:hidden}
.cc-fill{
  display:block;height:100%;border-radius:99px;width:0;
  background:linear-gradient(90deg,var(--cinnabar),#cf7a4a);
  transition:width .8s cubic-bezier(.22,.7,.3,1);
}
.cc-row:nth-child(2n) .cc-fill{background:linear-gradient(90deg,#8f6d33,#c9a45f)}
.cc-val{font-family:var(--mono);font-size:12px;color:var(--ink-3);text-align:right;font-variant-numeric:tabular-nums}
.cc-val b{color:var(--ink);font-weight:600}

.donut-wrap{display:flex;align-items:center;gap:26px}
.donut{
  position:relative;width:150px;height:150px;border-radius:50%;flex:0 0 auto;
  background:conic-gradient(var(--paper-3) 0 100%);
  transition:background .6s ease;
}
.donut::before{
  content:"";position:absolute;inset:12px;border-radius:50%;
  background:var(--paper-2);box-shadow:inset 0 0 0 1px var(--line);
}
.donut-hole{position:absolute;inset:0;display:grid;place-content:center;text-align:center;gap:0}
.donut-hole b{font-family:var(--serif);font-size:27px;line-height:1;font-weight:600}
.donut-hole span{font-size:10px;color:var(--ink-3);letter-spacing:.18em;margin-top:4px}
.legend{display:flex;flex-direction:column;gap:7px;min-width:0;flex:1}
.lg-row{display:flex;align-items:center;gap:8px;font-size:12px;color:var(--ink-2)}
.lg-dot{width:8px;height:8px;border-radius:2px;flex:0 0 auto}
.lg-name{flex:1;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;letter-spacing:.02em}
.lg-val{font-family:var(--mono);font-size:11.5px;color:var(--ink-3)}

/* =========================================================
   Recent mistakes (home)
   ========================================================= */
.recent-list{display:flex;flex-direction:column;gap:0;border-top:1px solid var(--line-2)}
.recent-item{
  display:grid;grid-template-columns:1fr auto auto;align-items:center;gap:18px;
  padding:15px 4px;border-bottom:1px solid var(--line);
  cursor:pointer;transition:background .16s,padding-left .16s;
}
.recent-item:hover{background:rgba(255,253,247,.85);padding-left:10px}
.ri-stem{font-family:var(--serif);font-size:15px;letter-spacing:.02em;line-height:1.5}
.ri-meta{display:flex;gap:10px;align-items:center;margin-top:4px;font-size:11.5px;color:var(--ink-3)}
.ri-count{font-family:var(--mono);font-size:12px;color:var(--ink-3);white-space:nowrap}
.ri-count b{color:var(--cinnabar);font-weight:600;font-size:14px}
.ri-go{color:var(--ink-3);font-size:16px;transition:transform .16s}
.recent-item:hover .ri-go{transform:translateX(3px);color:var(--cinnabar)}
.empty{
  padding:44px 20px;text-align:center;color:var(--ink-3);font-size:13px;
  border:1px dashed var(--line-2);border-radius:var(--radius);background:rgba(255,253,247,.4);
}
.empty b{display:block;font-family:var(--serif);font-size:16px;color:var(--ink-2);margin-bottom:6px;letter-spacing:.06em}

/* =========================================================
   Tags
   ========================================================= */
.tag{
  display:inline-flex;align-items:center;gap:4px;
  height:22px;padding:0 8px;border-radius:5px;
  font-size:11px;letter-spacing:.05em;white-space:nowrap;
  background:var(--paper-3);color:var(--ink-2);
}
.tag-cinnabar{background:var(--cinnabar-soft);color:#9c3125}
.tag-gold{background:var(--gold-soft);color:#8a6a2d}
.tag-jade{background:var(--jade-soft);color:var(--jade)}
.tag-indigo{background:var(--indigo-soft);color:var(--indigo)}
.tag-line{background:transparent;border:1px solid var(--line-2);color:var(--ink-3)}
.tag-ghost{background:rgba(26,29,35,.04);color:var(--ink-3)}
.tag-strong{background:var(--ink);color:#f6efe1}

.chip-row{display:flex;gap:7px;flex-wrap:wrap;align-items:center;flex:1}
.chip{
  height:31px;padding:0 13px;border-radius:99px;border:1px solid var(--line);
  font-size:12px;color:var(--ink-2);letter-spacing:.04em;background:rgba(255,253,247,.6);
  transition:all .16s;white-space:nowrap;
}
.chip:hover{border-color:var(--line-2);background:#fffdf7}
.chip.is-active{background:var(--ink);border-color:var(--ink);color:#f7f1e4}

/* =========================================================
   Filter bar
   ========================================================= */
.filter-bar{
  display:flex;gap:10px;align-items:center;flex-wrap:wrap;
  padding:14px 16px;background:rgba(255,253,247,.55);
  border:1px solid var(--line);border-radius:var(--radius);margin-bottom:22px;
}
.search{position:relative;flex:1 1 260px;min-width:200px}
.search svg{position:absolute;left:11px;top:50%;transform:translateY(-50%);width:15px;height:15px;color:var(--ink-3)}
.search input{width:100%;padding-left:34px;background:#fffdf7}
.segmented{display:flex;padding:3px;background:var(--paper-3);border-radius:9px;gap:2px}
.segmented button{
  height:29px;padding:0 12px;border-radius:7px;font-size:12px;color:var(--ink-3);
  letter-spacing:.04em;transition:all .16s;
}
.segmented button.is-active{background:#fffdf7;color:var(--ink);box-shadow:var(--shadow-sm);font-weight:500}
.star-filter{
  display:inline-flex;align-items:center;gap:6px;height:34px;padding:0 12px;
  border-radius:99px;border:1px solid var(--line);font-size:12px;color:var(--ink-2);
  background:rgba(255,253,247,.6);
}
.star-filter svg{width:14px;height:14px;fill:none}
.star-filter.is-active{background:var(--gold-soft);border-color:rgba(165,132,63,.4);color:#8a6a2d}
.star-filter.is-active svg{fill:#a5843f;stroke:#a5843f}

/* quick record */
.quick-record{
  display:flex;align-items:center;gap:10px;flex-wrap:wrap;
  padding:12px 14px;border-radius:var(--radius);
  border:1px solid rgba(176,57,45,.20);
  background:linear-gradient(120deg,rgba(176,57,45,.055),rgba(255,253,247,.9) 45%);
  margin-bottom:16px;
}
.qr-label{
  font-size:11px;letter-spacing:.18em;color:var(--cinnabar);white-space:nowrap;
  padding-right:12px;border-right:1px solid rgba(176,57,45,.2);
  font-weight:500;
}
.qr-stem{flex:1 1 300px;height:40px;background:#fffdf7}
.qr-count{display:flex;align-items:center;gap:5px;font-size:12px;color:var(--ink-3)}
.qr-count input{width:52px;height:40px;text-align:center;font-family:var(--mono);padding:0 4px}
.quick-record .btn{height:40px}

/* =========================================================
   Mistake board
   ========================================================= */
.mgroup{margin-bottom:26px}
.mgroup-head{
  display:flex;align-items:center;gap:12px;margin-bottom:12px;
  padding-bottom:9px;border-bottom:1px solid var(--line-2);
}
.mgroup-head h3{font-family:var(--serif);font-size:18px;letter-spacing:.06em;font-weight:600}
.mgroup-head .mg-count{font-family:var(--mono);font-size:11.5px;color:var(--ink-3)}
.mgroup-head .mg-bar{flex:1;height:1px;background:var(--line)}
.mgroup-head .mg-people{font-size:11.5px;color:var(--ink-3)}
.mgroup-head .mg-people b{color:var(--cinnabar);font-family:var(--mono)}

.mlist{display:grid;grid-template-columns:repeat(auto-fill,minmax(380px,1fr));gap:14px}
.mcard{
  background:var(--paper-2);border:1px solid var(--line);border-radius:14px;
  padding:16px 18px 13px;position:relative;overflow:hidden;
  transition:box-shadow .2s,border-color .2s,transform .2s;
}
.mcard:hover{box-shadow:var(--shadow-md);border-color:var(--line-2);transform:translateY(-1px)}
.mcard::before{
  content:"";position:absolute;left:0;top:0;bottom:0;width:3px;
  background:var(--mc,var(--cinnabar));opacity:.85;
}
.mcard-top{display:flex;align-items:center;gap:7px;flex-wrap:wrap;margin-bottom:9px}
.mcard-stem{font-family:var(--serif);font-size:15.5px;line-height:1.55;letter-spacing:.015em;cursor:pointer}
.mcard-stem:hover{color:var(--cinnabar)}
.mcard-answers{display:flex;flex-direction:column;gap:5px;margin:11px 0 0;font-size:12.5px}
.ans-row{display:flex;gap:8px;align-items:flex-start;line-height:1.6}
.ans-key{
  flex:0 0 auto;width:52px;font-size:10.5px;letter-spacing:.1em;color:var(--ink-3);padding-top:2px;
}
.ans-val{color:var(--ink-2)}
.ans-wrong .ans-val{color:#9c3125;text-decoration:line-through;text-decoration-color:rgba(176,57,45,.4)}
.ans-right .ans-val{color:var(--jade);font-weight:500}
.mcard-foot{
  display:flex;align-items:center;justify-content:space-between;gap:10px;
  margin-top:13px;padding-top:10px;border-top:1px dashed var(--line);
  font-size:11.5px;color:var(--ink-3);
}
.mcard-tags{display:flex;gap:6px;align-items:center;flex-wrap:wrap;min-width:0}
.mcard-actions{display:flex;gap:2px;align-items:center;opacity:.35;transition:opacity .18s}
.mcard:hover .mcard-actions{opacity:1}
.icon-btn{
  width:26px;height:26px;border-radius:6px;display:grid;place-items:center;
  color:var(--ink-3);transition:all .15s;
}
.icon-btn:hover{background:var(--paper-3);color:var(--ink)}
.icon-btn.danger:hover{background:var(--cinnabar-soft);color:var(--cinnabar)}
.icon-btn svg{width:15px;height:15px}
.review-dot{width:18px;height:18px;border-radius:4px;border:1.5px solid var(--line-2);display:grid;place-items:center;color:transparent;margin-right:4px;transition:all .15s}
.review-dot.done{background:var(--jade);border-color:var(--jade);color:#fff}
.review-dot svg{width:10px;height:10px;stroke-width:2.6}

/* =========================================================
   Concept grid
   ========================================================= */
.concept-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:16px}
.ccard{
  position:relative;background:var(--paper-2);border:1px solid var(--line);border-radius:14px;
  padding:20px 20px 16px;display:flex;flex-direction:column;gap:10px;min-height:196px;
  transition:transform .2s,box-shadow .2s,border-color .2s;overflow:hidden;
}
.ccard::after{
  content:"";position:absolute;right:-30px;bottom:-38px;width:110px;height:110px;border-radius:50%;z-index:0;
  background:radial-gradient(circle,rgba(165,132,63,.10),transparent 68%);
  pointer-events:none;
}
.ccard:hover{transform:translateY(-3px);box-shadow:var(--shadow-md);border-color:var(--line-2)}
.ccard-top{display:flex;align-items:flex-start;justify-content:space-between;gap:10px}
.ccard-name{font-family:var(--serif);font-size:20px;letter-spacing:.05em;font-weight:600;line-height:1.3}
.ccard-alias{font-size:11px;color:var(--ink-3);margin-top:2px;letter-spacing:.02em}
.ccard-def{
  font-size:12.8px;line-height:1.85;color:var(--ink-2);letter-spacing:.01em;
  display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden;
  flex:1;
}
.ccard-foot{display:flex;align-items:center;justify-content:space-between;gap:8px;margin-top:2px;pointer-events:none}
.ccard-tags{display:flex;gap:5px;flex-wrap:wrap}
.fav-btn{color:var(--ink-3);transition:color .16s,transform .16s;flex:0 0 auto;pointer-events:auto}
.fav-btn svg{width:17px;height:17px;fill:none}
.fav-btn:hover{transform:scale(1.12)}
.fav-btn.on{color:var(--gold)}
.fav-btn.on svg{fill:var(--gold);stroke:var(--gold)}
.ccard-open{
  position:absolute;inset:0;cursor:pointer;z-index:1;
}
.ccard-foot, .ccard-top .fav-btn{position:relative;z-index:2}
.concept-detail h2{font-family:var(--serif);font-size:26px;letter-spacing:.05em;margin-bottom:4px}
.detail-block{margin-top:20px}
.detail-block h4{font-size:11px;letter-spacing:.18em;color:var(--ink-3);margin-bottom:8px;font-weight:500}
.detail-block p{font-size:13.5px;line-height:1.9;color:var(--ink-2)}
.detail-list{list-style:none;padding:0;margin:0;display:flex;flex-direction:column;gap:7px}
.detail-list li{position:relative;padding-left:16px;font-size:13.2px;line-height:1.8;color:var(--ink-2)}
.detail-list li::before{content:"";position:absolute;left:0;top:10px;width:5px;height:5px;border-radius:1px;background:var(--gold);transform:rotate(45deg)}
.confusion{background:var(--cinnabar-soft);border-left:2px solid var(--cinnabar);padding:12px 14px;border-radius:0 8px 8px 0;font-size:12.8px;line-height:1.85;color:#7f352b}
.related-mistake{display:flex;gap:10px;padding:10px 0;border-bottom:1px solid var(--line);font-size:12.5px;color:var(--ink-2);line-height:1.6;align-items:flex-start}
.related-mistake:last-child{border-bottom:0}
.related-mistake .rm-tag{flex:0 0 auto;margin-top:2px}

/* =========================================================
   Slides manager
   ========================================================= */
.deck-meta{
  display:grid;grid-template-columns:1.1fr 1fr;gap:24px;margin-bottom:22px;
}
.slide-list{display:flex;flex-direction:column;gap:10px}
.slide-item{
  display:grid;grid-template-columns:44px 1fr auto;gap:16px;align-items:center;
  background:var(--paper-2);border:1px solid var(--line);border-radius:12px;
  padding:13px 16px;transition:all .18s;cursor:pointer;
}
.slide-item:hover{border-color:var(--line-2);box-shadow:var(--shadow-sm);transform:translateX(2px)}
.slide-idx{
  font-family:var(--serif);font-size:18px;color:var(--ink-3);text-align:center;
  font-variant-numeric:tabular-nums;letter-spacing:.02em;
}
.slide-item:hover .slide-idx{color:var(--cinnabar)}
.slide-info{min-width:0}
.slide-title{font-family:var(--serif);font-size:15.5px;letter-spacing:.03em;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.slide-note{font-size:11.5px;color:var(--ink-3);white-space:nowrap;overflow:hidden;text-overflow:ellipsis;margin-top:3px}
.slide-actions{display:flex;gap:2px;align-items:center;opacity:.4;transition:opacity .18s}
.slide-item:hover .slide-actions{opacity:1}
.type-tag{display:inline-block;font-size:10px;letter-spacing:.1em;color:var(--ink-3);border:1px solid var(--line);padding:0 6px;border-radius:4px;margin-right:8px;vertical-align:1px}

/* =========================================================
   Tools
   ========================================================= */
.grid-tools{grid-template-columns:1fr 1fr}
.timer-display{
  font-family:var(--mono);font-size:64px;line-height:1;letter-spacing:.02em;
  text-align:center;padding:14px 0 18px;font-variant-numeric:tabular-nums;
  color:var(--ink);
}
.timer-display.warn{color:var(--cinnabar)}
.timer-bar{height:4px;border-radius:99px;background:var(--paper-3);overflow:hidden;margin-bottom:18px}
.timer-bar i{display:block;height:100%;width:100%;background:linear-gradient(90deg,var(--cinnabar),#d08a52);transition:width .9s linear}
.timer-presets{display:flex;gap:7px;flex-wrap:wrap;margin-bottom:18px}
.timer-presets button{
  height:31px;padding:0 13px;border-radius:99px;border:1px solid var(--line);
  font-size:12px;color:var(--ink-2);transition:all .16s;background:rgba(255,253,247,.6);
}
.timer-presets button.is-active{background:var(--ink);color:#f6efe1;border-color:var(--ink)}
.timer-actions{display:flex;gap:10px}
.picker-stage{
  height:132px;border-radius:12px;border:1px dashed var(--line-2);
  display:grid;place-items:center;margin-bottom:16px;
  font-family:var(--serif);font-size:30px;letter-spacing:.1em;color:var(--ink);
  background:radial-gradient(circle at 50% 40%,rgba(165,132,63,.08),transparent 70%);
  transition:all .2s;
}
.picker-stage.rolling{color:var(--ink-3);font-size:24px}
.picker-stage.picked{color:var(--cinnabar);font-size:38px;animation:pop .5s cubic-bezier(.2,1.4,.4,1)}
@keyframes pop{0%{transform:scale(.8);opacity:.2}100%{transform:scale(1);opacity:1}}
.pick-history{display:flex;gap:6px;flex-wrap:wrap;margin-top:14px;min-height:22px}
.pick-history span{font-size:11px;color:var(--ink-3);padding:2px 8px;background:var(--paper-3);border-radius:99px}
.shortcuts{margin-top:20px}
.shortcut-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:12px 20px}
.shortcut-grid div{display:flex;align-items:center;gap:10px;font-size:12.5px;color:var(--ink-2)}
kbd{
  display:inline-grid;place-items:center;min-width:30px;height:25px;padding:0 7px;
  border-radius:6px;border:1px solid var(--line-2);border-bottom-width:2px;
  background:var(--paper-2);font-family:var(--mono);font-size:11px;color:var(--ink-2);
}

/* =========================================================
   Course catalog
   ========================================================= */
.cat-progress{min-width:248px;padding:12px 16px;border:1px solid var(--line);border-radius:12px;background:rgba(255,253,247,.6)}
.cat-progress-top{display:flex;align-items:baseline;gap:6px}
.cat-progress-top b{font-family:var(--serif);font-size:26px;line-height:1;letter-spacing:.02em;font-weight:600}
.cat-progress-top span{font-size:11.5px;color:var(--ink-3);letter-spacing:.04em}
.cat-progress-top i{font-style:normal;color:var(--ink-2)}
.cat-progress-bar{height:4px;border-radius:99px;background:var(--paper-3);overflow:hidden;margin:9px 0 7px}
.cat-progress-bar i{display:block;height:100%;width:0;border-radius:99px;background:linear-gradient(90deg,var(--cinnabar),#cf8b52);transition:width .5s ease}
.cat-progress-foot{font-size:10.5px;color:var(--ink-3);letter-spacing:.06em}

.cat-tabs{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:18px}
.cat-tab{display:inline-flex;align-items:center;gap:8px;height:36px;padding:0 15px;border-radius:99px;border:1px solid var(--line);background:rgba(255,253,247,.6);font-size:12.5px;color:var(--ink-2);letter-spacing:.03em;transition:all .16s}
.cat-tab em{font-style:normal;font-family:var(--mono);font-size:10.5px;color:var(--ink-3);padding:1px 6px;border-radius:99px;background:var(--paper-3)}
.cat-tab:hover{border-color:var(--line-2);background:#fffdf7}
.cat-tab.is-active{background:var(--ink);border-color:var(--ink);color:#f7f1e4}
.cat-tab.is-active em{background:rgba(255,255,255,.14);color:rgba(255,255,255,.72)}

.cat-layout{display:grid;grid-template-columns:296px minmax(0,1fr);gap:20px;align-items:start}
.cat-nav{padding:10px;position:sticky;top:96px;max-height:calc(100vh - 130px);overflow-y:auto;scrollbar-width:thin}
.cat-nav::-webkit-scrollbar{width:6px}
.cat-nav::-webkit-scrollbar-thumb{background:var(--line-2);border-radius:99px}
.unit-block{margin-bottom:8px}
.unit-name{font-size:10px;letter-spacing:.16em;color:var(--ink-3);padding:9px 10px 6px;line-height:1.5;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.unit-name b{color:var(--ink-2);font-weight:600;letter-spacing:.1em}
.lesson-item{position:relative;display:grid;grid-template-columns:22px 1fr auto;gap:8px;align-items:start;width:100%;text-align:left;padding:8px 10px;border-radius:8px;color:var(--ink-2);transition:background .14s,color .14s}
.lesson-item:hover{background:rgba(26,29,35,.04)}
.lesson-item.is-active{background:var(--cinnabar-soft);color:var(--ink)}
.lesson-item.is-active::before{content:"";position:absolute;left:0;top:9px;bottom:9px;width:2px;border-radius:2px;background:var(--cinnabar)}
.lesson-num{font-family:var(--mono);font-size:10.5px;color:var(--ink-3);padding-top:3px;letter-spacing:.02em}
.lesson-name{font-size:12.8px;line-height:1.55;letter-spacing:.01em}
.lesson-item.is-active .lesson-name{font-weight:500}
.lesson-dot{min-width:6px;height:6px;border-radius:99px;margin-top:7px;background:transparent;box-shadow:inset 0 0 0 1px var(--line-2);display:grid;place-items:center;font-family:var(--mono);font-size:9px;line-height:1;color:#fff}
.lesson-dot.has{min-width:15px;height:15px;padding:0 4px;margin-top:4px;background:var(--jade);box-shadow:0 0 0 3px rgba(56,104,90,.12)}

.cat-panel{padding:26px 30px 24px;min-height:540px}
.lesson-eyebrow{font-size:10.5px;letter-spacing:.2em;color:var(--cinnabar)}
.lesson-title{font-family:var(--serif);font-size:28px;line-height:1.4;letter-spacing:.04em;margin-top:8px;font-weight:600}
.lesson-focus{font-size:13px;line-height:1.95;color:var(--ink-2);margin-top:12px;max-width:760px;letter-spacing:.01em}
.lesson-focus::before{content:"学习聚焦 · ";font-size:10.5px;letter-spacing:.16em;color:var(--gold)}
.lesson-meta{display:flex;gap:7px;flex-wrap:wrap;align-items:center;margin-top:15px}

.upload-zone{margin-top:22px;border:1.5px dashed var(--line-2);border-radius:14px;background:rgba(245,241,232,.5);padding:26px 20px;text-align:center;transition:all .18s;cursor:pointer}
.upload-zone:hover{border-color:rgba(176,57,45,.36);background:rgba(176,57,45,.03)}
.upload-zone.is-drag{border-color:var(--cinnabar);background:var(--cinnabar-soft)}
.uz-icon{width:40px;height:40px;margin:0 auto 10px;border-radius:10px;display:grid;place-items:center;background:#fffdf7;border:1px solid var(--line);color:var(--cinnabar)}
.uz-icon svg{width:19px;height:19px}
.uz-title{font-family:var(--serif);font-size:16px;letter-spacing:.05em}
.uz-sub{font-size:11px;color:var(--ink-3);margin-top:6px;line-height:1.7;letter-spacing:.02em}
.uz-btn{margin-top:13px}

.file-list{margin-top:14px;display:flex;flex-direction:column;gap:8px}
.file-row{display:grid;grid-template-columns:38px 1fr auto;gap:12px;align-items:center;padding:11px 13px;border:1px solid var(--line);border-radius:10px;background:#fffdf7;transition:border-color .16s,box-shadow .16s}
.file-row:hover{border-color:var(--line-2);box-shadow:var(--shadow-sm)}
.file-ico{width:36px;height:36px;border-radius:8px;display:grid;place-items:center;font-family:var(--mono);font-size:9.5px;letter-spacing:.04em;background:var(--ink);color:#f6efe1}
.file-ico.pdf{background:var(--cinnabar)}
.file-ico.key{background:var(--indigo)}
.file-name{font-size:13px;color:var(--ink);white-space:nowrap;overflow:hidden;text-overflow:ellipsis;letter-spacing:.01em}
.file-meta{font-size:10.5px;color:var(--ink-3);margin-top:2px;letter-spacing:.04em}
.file-actions{display:flex;align-items:center;gap:2px}
.file-actions button{height:28px;padding:0 10px;border-radius:6px;font-size:11.5px;color:var(--ink-3);letter-spacing:.03em;transition:all .15s}
.file-actions button:hover{background:var(--paper-3);color:var(--ink)}
.file-actions button.danger:hover{background:var(--cinnabar-soft);color:var(--cinnabar)}
.file-empty{margin-top:14px;border:1px solid var(--line);border-radius:10px;padding:14px;text-align:center;font-size:11.5px;color:var(--ink-3);background:rgba(245,241,232,.4)}

.lesson-actions{display:flex;gap:10px;flex-wrap:wrap;margin-top:22px;padding-top:18px;border-top:1px dashed var(--line)}
.lesson-actions .spacer{flex:1}
.cat-note{margin-top:16px;font-size:10.5px;color:var(--ink-3);line-height:1.8;letter-spacing:.02em;display:flex;gap:6px;align-items:flex-start}
.cat-note svg{width:12px;height:12px;flex:0 0 auto;margin-top:3px;color:var(--gold)}

/* =========================================================
   Presentation
   ========================================================= */
.present{
  position:fixed;inset:0;z-index:100;display:none;
  grid-template-rows:auto 1fr auto auto;
  background:#14161c;color:#f2ece0;
  --p-bg:#14161c;
  --p-line:rgba(242,236,224,.12);
  --p-muted:rgba(242,236,224,.48);
  --p-gold:#c9a75f;
  --p-cinnabar:#c65a45;
}
.present.is-open{display:grid;animation:presIn .32s ease}
@keyframes presIn{from{opacity:0}to{opacity:1}}
.present::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:
    radial-gradient(70% 55% at 12% 0%,rgba(201,167,95,.10),transparent 60%),
    radial-gradient(60% 50% at 92% 100%,rgba(198,90,69,.10),transparent 62%),
    radial-gradient(circle at 50% 45%,#1c2029 0%,#12141a 75%);
}
.present > *{position:relative;z-index:1}

.present-top{
  display:flex;align-items:center;justify-content:space-between;gap:20px;
  padding:16px 34px;border-bottom:1px solid var(--p-line);
}
.present-brand{display:flex;align-items:center;gap:13px;min-width:0}
.present-seal{
  width:34px;height:34px;border-radius:6px;flex:0 0 auto;
  display:grid;place-items:center;font-family:var(--serif);font-size:19px;
  background:linear-gradient(150deg,#c65a45,#8f2c23);color:#fbf3e4;
  box-shadow:inset 0 0 0 1px rgba(255,255,255,.18);
}
.present-course{font-size:10.5px;letter-spacing:.22em;color:var(--p-muted)}
.present-title{font-family:var(--serif);font-size:14px;letter-spacing:.06em;color:rgba(242,236,224,.86);margin-top:1px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.present-tools{display:flex;align-items:center;gap:8px;flex:0 0 auto}
.present-timer{
  font-family:var(--mono);font-size:13px;color:var(--p-gold);letter-spacing:.08em;
  padding:4px 10px;border:1px solid rgba(201,167,95,.3);border-radius:6px;
  font-variant-numeric:tabular-nums;margin-right:6px;
}
.pbtn{
  height:30px;padding:0 12px;border-radius:6px;font-size:11.5px;letter-spacing:.08em;
  color:rgba(242,236,224,.62);border:1px solid transparent;transition:all .16s;
}
.pbtn:hover{color:#fff;background:rgba(255,255,255,.07);border-color:var(--p-line)}
.pbtn.is-on{color:var(--p-gold);background:rgba(201,167,95,.10);border-color:rgba(201,167,95,.28)}
.pbtn-quit{color:#eab5aa}
.pbtn-quit:hover{background:rgba(198,90,69,.16);color:#ffd9d0}

.present-body{display:flex;min-height:0;position:relative}
.stage{
  flex:1;min-width:0;display:flex;align-items:center;justify-content:center;
  padding:34px 56px;overflow:hidden;
}
.slide-frame{width:100%;max-width:1180px;animation:slideIn .45s cubic-bezier(.22,.7,.3,1)}
@keyframes slideIn{from{opacity:0;transform:translateY(14px)}to{opacity:1;transform:none}}
.slide-frame.is-back{animation-name:slideInBack}
@keyframes slideInBack{from{opacity:0;transform:translateY(-14px)}to{opacity:1;transform:none}}

/* slide typography (dark) */
.s-kicker{
  font-size:12px;letter-spacing:.34em;color:var(--p-gold);text-transform:uppercase;
  display:flex;align-items:center;gap:12px;margin-bottom:22px;
}
.s-kicker::after{content:"";height:1px;width:64px;background:linear-gradient(90deg,rgba(201,167,95,.6),transparent)}
.s-h1{
  font-family:var(--serif);font-size:clamp(42px,5vw,68px);line-height:1.22;
  letter-spacing:.06em;font-weight:600;color:#fbf6ea;
}
.s-h2{
  font-family:var(--serif);font-size:clamp(30px,3.1vw,42px);line-height:1.3;
  letter-spacing:.05em;font-weight:600;color:#fbf6ea;margin-bottom:8px;
}
.s-sub{font-size:15px;line-height:1.9;color:rgba(242,236,224,.66);letter-spacing:.03em;max-width:840px}
.s-rule{width:58px;height:2px;background:var(--p-cinnabar);margin:26px 0 22px}
.s-cover .s-sub{max-width:760px;margin-top:18px}
.s-cover-meta{display:flex;gap:22px;margin-top:38px;font-size:11.5px;letter-spacing:.16em;color:rgba(242,236,224,.40)}
.s-cover-meta span{display:flex;align-items:center;gap:8px}
.s-cover-meta span::before{content:"";width:4px;height:4px;background:var(--p-gold);border-radius:1px;transform:rotate(45deg)}

.s-bullets{display:flex;flex-direction:column;gap:20px;margin-top:34px}
.s-bullet{
  display:grid;grid-template-columns:38px 1fr;gap:18px;align-items:flex-start;
  border-left:1px solid rgba(242,236,224,.10);padding-left:20px;
  animation:bulletIn .5s backwards;animation-delay:calc(var(--i)*80ms);
}
@keyframes bulletIn{from{opacity:0;transform:translateX(-12px)}to{opacity:1;transform:none}}
.s-bullet b{
  font-family:var(--mono);font-size:12px;color:var(--p-gold);letter-spacing:.06em;
  padding-top:7px;font-weight:400;
}
.s-bullet p{font-family:var(--serif);font-size:clamp(19px,1.85vw,25px);line-height:1.62;letter-spacing:.03em;color:rgba(250,244,232,.92)}
.s-bullet p em{font-style:normal;color:var(--p-gold);border-bottom:1px solid rgba(201,167,95,.35);padding-bottom:1px}

/* compare */
.s-compare{display:grid;grid-template-columns:1fr 56px 1fr;gap:0;margin-top:34px;align-items:stretch}
.s-col{
  border:1px solid rgba(242,236,224,.12);border-radius:10px;padding:24px 26px;
  background:linear-gradient(180deg,rgba(255,255,255,.035),rgba(255,255,255,.008));
}
.s-col h4{font-family:var(--serif);font-size:20px;letter-spacing:.08em;margin-bottom:4px;color:#fbf6ea}
.s-col .s-col-sub{font-size:11px;letter-spacing:.16em;color:var(--p-muted);margin-bottom:16px}
.s-col ul{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:11px}
.s-col li{position:relative;padding-left:15px;font-size:15px;line-height:1.7;color:rgba(242,236,224,.80)}
.s-col li::before{content:"";position:absolute;left:0;top:9px;width:5px;height:5px;background:var(--p-gold);border-radius:1px;transform:rotate(45deg);opacity:.8}
.s-col:nth-of-type(2){border-color:rgba(201,167,95,.22)}
.s-vs{display:grid;place-items:center;font-family:var(--serif);font-size:13px;letter-spacing:.1em;color:var(--p-muted)}

/* timeline */
.s-timeline{display:flex;align-items:flex-start;gap:0;margin-top:56px;position:relative;padding:0 4px}
.s-timeline::before{
  content:"";position:absolute;left:0;right:0;top:46px;height:1px;
  background:linear-gradient(90deg,transparent,rgba(201,167,95,.45) 12%,rgba(201,167,95,.45) 88%,transparent);
}
.tl-node{flex:1;display:flex;flex-direction:column;align-items:center;text-align:center;position:relative;padding:0 8px}
.tl-time{font-family:var(--mono);font-size:12.5px;letter-spacing:.04em;color:var(--p-gold);height:26px}
.tl-dot{
  width:11px;height:11px;border-radius:50%;background:var(--p-bg);
  border:1.5px solid var(--p-gold);margin:15px 0 18px;position:relative;z-index:1;
}
.tl-node:nth-child(3n) .tl-dot{background:var(--p-cinnabar);border-color:var(--p-cinnabar);box-shadow:0 0 0 4px rgba(198,90,69,.16)}
.tl-title{font-family:var(--serif);font-size:16px;letter-spacing:.04em;color:#fbf6ea;line-height:1.5}
.tl-text{font-size:11.5px;line-height:1.7;color:rgba(242,236,224,.5);margin-top:6px;letter-spacing:.02em}

/* quote */
.s-quote{max-width:900px}
.s-quote .q-mark{font-family:var(--serif);font-size:88px;line-height:.6;color:rgba(201,167,95,.35);margin-bottom:14px}
.s-quote blockquote{
  margin:0;font-family:var(--serif);font-size:clamp(25px,3vw,38px);line-height:1.7;
  letter-spacing:.05em;color:#fbf6ea;
}
.s-quote .q-src{margin-top:26px;font-size:12px;letter-spacing:.2em;color:var(--p-muted)}

/* concept slide */
.s-concept{display:grid;grid-template-columns:280px 1fr;gap:44px;align-items:start;margin-top:26px}
.s-concept-side{border-right:1px solid rgba(242,236,224,.12);padding-right:34px}
.s-concept-side .sc-name{font-family:var(--serif);font-size:clamp(30px,3vw,40px);line-height:1.3;letter-spacing:.06em;color:#fbf6ea}
.s-concept-side .sc-alias{font-size:11.5px;color:var(--p-muted);margin-top:8px;letter-spacing:.06em}
.s-concept-side .sc-era{margin-top:18px;display:flex;gap:6px;flex-wrap:wrap}
.sc-chip{font-size:10.5px;letter-spacing:.1em;border:1px solid rgba(201,167,95,.32);color:var(--p-gold);padding:2px 8px;border-radius:4px}
.s-def{font-family:var(--serif);font-size:clamp(17px,1.65vw,22px);line-height:1.85;color:rgba(250,244,232,.90);letter-spacing:.02em}
.s-points{list-style:none;margin:24px 0 0;padding:0;display:flex;flex-direction:column;gap:12px}
.s-points li{position:relative;padding-left:18px;font-size:15px;line-height:1.75;color:rgba(242,236,224,.72)}
.s-points li::before{content:"";position:absolute;left:0;top:9px;width:6px;height:6px;border:1px solid var(--p-gold);transform:rotate(45deg)}

/* question */
.s-question{margin-top:26px}
.q-stem{font-family:var(--serif);font-size:clamp(20px,2vw,26px);line-height:1.8;letter-spacing:.02em;color:#fbf6ea;max-width:960px}
.q-options{display:grid;grid-template-columns:1fr 1fr;gap:12px 26px;margin-top:30px}
.q-opt{
  display:flex;gap:12px;align-items:flex-start;padding:13px 16px;border-radius:8px;
  border:1px solid rgba(242,236,224,.10);font-size:15px;line-height:1.7;color:rgba(242,236,224,.78);
  background:rgba(255,255,255,.02);
}
.q-opt b{font-family:var(--mono);color:var(--p-gold);font-weight:400;font-size:13px;padding-top:2px}
.q-answer{
  margin-top:28px;border-top:1px solid rgba(242,236,224,.12);padding-top:18px;
  display:flex;align-items:center;gap:14px;cursor:pointer;
}
.q-answer .qa-hint{font-size:12px;letter-spacing:.14em;color:var(--p-muted);border:1px dashed rgba(242,236,224,.25);padding:5px 12px;border-radius:5px}
.q-answer .qa-body{display:none;font-size:14.5px;line-height:1.8;color:#dfd3b8;flex:1}
.q-answer.is-revealed .qa-hint{display:none}
.q-answer.is-revealed .qa-body{display:block;animation:viewIn .28s ease}

/* end slide */
.s-end{text-align:center;max-width:760px;margin:0 auto}
.s-end .e-seal{
  width:58px;height:58px;margin:0 auto 26px;border:1px solid rgba(176,57,45,.5);border-radius:4px;
  display:grid;place-items:center;font-family:var(--serif);font-size:26px;color:#d8756a;
  transform:rotate(-3deg);background:rgba(176,57,45,.08);
}
.s-end h2{font-family:var(--serif);font-size:clamp(28px,3vw,40px);letter-spacing:.1em;color:#fbf6ea;line-height:1.5}
.s-end p{margin-top:16px;font-size:14px;color:var(--p-muted);letter-spacing:.06em;line-height:2}

/* thumbs */
.thumbs{
  width:0;overflow:hidden;transition:width .28s ease;
  border-left:1px solid var(--p-line);background:rgba(0,0,0,.18);
}
.thumbs.is-open{width:196px}
.thumbs-inner{padding:18px 14px;display:flex;flex-direction:column;gap:8px;height:100%;overflow-y:auto}
.thumb{
  display:grid;grid-template-columns:22px 1fr;gap:9px;align-items:center;
  padding:8px 9px;border-radius:6px;border:1px solid transparent;
  font-size:11.5px;color:rgba(242,236,224,.55);text-align:left;line-height:1.45;
  transition:all .15s;
}
.thumb:hover{background:rgba(255,255,255,.05);color:#fff}
.thumb.is-active{border-color:rgba(201,167,95,.4);background:rgba(201,167,95,.09);color:#fbf6ea}
.thumb b{font-family:var(--mono);font-weight:400;color:var(--p-gold);font-size:11px;text-align:center}

/* notes */
.notes{
  display:none;border-top:1px solid var(--p-line);
  padding:16px 34px 18px;background:rgba(0,0,0,.22);
}
.notes.is-open{display:block}
.notes-label{font-size:10px;letter-spacing:.24em;color:var(--p-gold);margin-bottom:7px}
.notes-text{font-size:13px;line-height:1.85;color:rgba(242,236,224,.62);max-width:1000px;letter-spacing:.02em}

/* footer */
.present-foot{
  display:grid;grid-template-columns:auto 1fr auto;gap:24px;align-items:center;
  padding:12px 34px 14px;border-top:1px solid var(--p-line);
}
.pnav{display:flex;align-items:center;gap:8px}
.pnav-btn{
  width:30px;height:30px;border-radius:6px;border:1px solid var(--p-line);
  color:rgba(242,236,224,.6);font-size:14px;display:grid;place-items:center;transition:all .15s;
}
.pnav-btn:hover{background:rgba(255,255,255,.08);color:#fff}
.ppage{font-family:var(--mono);font-size:12px;color:var(--p-muted);letter-spacing:.06em;margin-left:4px}
.ppage b{color:#fbf6ea;font-weight:500}
.pprogress{height:2px;background:rgba(242,236,224,.12);border-radius:99px;overflow:hidden}
.pprogress i{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--p-cinnabar),var(--p-gold));transition:width .35s ease}
.phint{font-size:10.5px;letter-spacing:.1em;color:rgba(242,236,224,.3);white-space:nowrap}

/* =========================================================
   Modal / toast
   ========================================================= */
.modal-mask{
  position:fixed;inset:0;z-index:1300;background:rgba(20,22,28,.42);
  backdrop-filter:blur(3px);display:grid;place-items:center;padding:32px;
  animation:maskIn .22s ease;
}
@keyframes maskIn{from{opacity:0}to{opacity:1}}
.modal{
  width:100%;max-width:620px;max-height:86vh;overflow:auto;
  background:var(--paper-2);border-radius:18px;border:1px solid var(--line);
  box-shadow:0 50px 100px -40px rgba(0,0,0,.6);
  animation:modalIn .3s cubic-bezier(.2,.8,.3,1);
}
.modal.wide{max-width:760px}
@keyframes modalIn{from{opacity:0;transform:translateY(18px) scale(.98)}to{opacity:1;transform:none}}
.modal-head{
  display:flex;align-items:flex-start;justify-content:space-between;gap:16px;
  padding:24px 28px 16px;
}
.modal-head h3{font-family:var(--serif);font-size:22px;letter-spacing:.05em}
.modal-head p{font-size:12px;color:var(--ink-3);margin-top:4px}
.modal-close{width:30px;height:30px;border-radius:8px;display:grid;place-items:center;color:var(--ink-3);font-size:18px}
.modal-close:hover{background:var(--paper-3);color:var(--ink)}
.modal-body{padding:0 28px 4px}
.modal-foot{
  display:flex;justify-content:flex-end;gap:10px;
  padding:18px 28px 24px;position:sticky;bottom:0;
  background:linear-gradient(rgba(255,253,247,0),var(--paper-2) 32%);
}
.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.form-grid .full{grid-column:1/-1}
.form-field label{display:block;font-size:11px;letter-spacing:.14em;color:var(--ink-3);margin-bottom:6px}
.form-field input,.form-field select,.form-field textarea{width:100%}
.form-hint{font-size:11px;color:var(--ink-3);margin-top:5px;line-height:1.6}

.toast-root{position:fixed;left:50%;bottom:34px;transform:translateX(-50%);z-index:1400;display:flex;flex-direction:column;gap:8px;align-items:center;pointer-events:none}
.toast{
  padding:10px 18px;border-radius:99px;background:rgba(24,27,33,.94);color:#f6efe1;
  font-size:12.5px;letter-spacing:.04em;box-shadow:0 10px 30px -10px rgba(0,0,0,.5);
  animation:toastIn .28s ease;display:flex;align-items:center;gap:8px;
}
.toast::before{content:"";width:5px;height:5px;border-radius:50%;background:var(--gold)}
@keyframes toastIn{from{opacity:0;transform:translateY(10px)}to{opacity:1;transform:none}}

/* =========================================================
   Responsive
   ========================================================= */
@media (max-width:1180px){
  .main{padding:0 26px 60px}
  .stat-row{grid-template-columns:repeat(2,1fr)}
  .grid-2{grid-template-columns:1fr}
  .hero{grid-template-columns:1fr;gap:26px;padding:30px}
  .hero-side{flex-direction:row;justify-content:flex-start;align-items:center;gap:28px}
  .hero-watermark{font-size:220px;right:-20px}
  .deck-meta{grid-template-columns:1fr}
  .cat-layout{grid-template-columns:250px minmax(0,1fr)}
}
@media (max-width:900px){
  .app{grid-template-columns:68px minmax(0,1fr)}
  .rail-btn span{display:none}
  .rail-btn{padding:12px 0}
  .brand-sub{display:none}
  .main{padding:0 18px 56px}
  .clock{display:none}
  .mlist{grid-template-columns:1fr}
  .grid-tools{grid-template-columns:1fr}
  .q-options{grid-template-columns:1fr}
  .s-concept{grid-template-columns:1fr;gap:24px}
  .s-concept-side{border-right:0;border-bottom:1px solid rgba(242,236,224,.12);padding:0 0 18px}
  .stage{padding:22px 24px}
  .present-top,.present-foot{padding-left:18px;padding-right:18px}
  .phint{display:none}
  .thumbs.is-open{width:0}
  .topbar{flex-wrap:wrap;gap:10px}
  .cat-layout{grid-template-columns:1fr}
  .cat-nav{position:static;max-height:300px}
  .cat-panel{padding:20px 18px;min-height:0}
  .cat-progress{min-width:0;width:100%}
  .lesson-title{font-size:23px}
}

/* =========================================================
   教材标识 / PPT 在线演示
   ========================================================= */
.tab-flag{font-style:normal;font-size:10px;font-weight:600;padding:1.5px 7px;border-radius:99px;background:var(--cinnabar-soft);color:#9c3125;letter-spacing:.06em}
.cat-tab.is-active .tab-flag{background:rgba(224,110,90,.30);color:#ffd9cf}
.lesson-badge{font-style:normal;font-size:9px;font-weight:600;padding:1.5px 5px;border-radius:5px;background:var(--cinnabar-soft);color:#9c3125;letter-spacing:.08em;white-space:nowrap;align-self:center}
.lesson-item.is-active .lesson-badge{background:rgba(176,57,45,.20)}

.pptv-mask{position:fixed;inset:0;z-index:1000;background:#15171d;display:flex;flex-direction:column;animation:maskIn .2s ease}
.pptv-lock{overflow:hidden}
.pptv-bar{flex:0 0 48px;display:flex;align-items:center;gap:16px;padding:0 18px;background:rgba(21,23,29,.97);border-bottom:1px solid rgba(255,255,255,.09)}
.pptv-name{font-size:13px;color:#ece5d6;letter-spacing:.03em;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;min-width:0}
.pptv-nav{display:flex;align-items:center;gap:7px;flex:0 0 auto}
.pptv-nav[hidden]{display:none}
.pptv-counter{min-width:62px;text-align:center;color:#ece5d6;font:600 12px/1.2 ui-monospace,SFMono-Regular,Consolas,monospace;letter-spacing:.04em}
.pptv-hint{font-size:11px;color:rgba(236,229,214,.4);margin-left:auto;letter-spacing:.05em;white-space:nowrap}
.pptv-close{height:30px;padding:0 14px;border-radius:7px;font-size:12px;color:#ece5d6;background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.14);letter-spacing:.06em;transition:background .15s}
.pptv-close:hover{background:rgba(255,255,255,.16)}
.pptv-close:disabled{opacity:.35;cursor:not-allowed;background:rgba(255,255,255,.04)}
.pptv-body{flex:1;overflow:auto;position:relative;-webkit-overflow-scrolling:touch}
.pptv-body.is-presenting{overflow:hidden}
#pptvStage{min-height:100%;padding:26px;display:flex;flex-direction:column;align-items:center;gap:20px}
#pptvStage .slide{background:#fff;box-shadow:0 12px 38px rgba(0,0,0,.55);border-radius:2px;overflow:hidden}
#pptvStage .pptx-wrapper{display:flex;flex-direction:column;align-items:center;gap:20px}
#pptvStage.pptv-present{position:relative;width:100%;height:100%;min-height:100%;padding:0;display:block;overflow:hidden}
#pptvStage.pptv-present .slide{display:none;position:absolute;left:50%;top:50%;margin:0;transform:translate(-50%,-50%) scale(var(--pptv-scale,1));transform-origin:center center;content-visibility:visible}
#pptvStage.pptv-present .slide.is-current{display:block}
.pptv-pdf{position:absolute;inset:0;width:100%;height:100%;border:0;background:#3c3f45}
.pptv-loading{color:#cfc8b8;font-size:13.5px;line-height:2;text-align:center;padding:70px 40px;letter-spacing:.05em}

/* 后台解析中的过渡态 */
.pptv-spinner{width:44px;height:44px;margin:0 auto 18px;border-radius:50%;border:3px solid rgba(255,255,255,.14);border-top-color:#e06e5a;animation:pptvSpin .9s linear infinite}
@keyframes pptvSpin{to{transform:rotate(360deg)}}
.pptv-parse-title{font-size:15px;letter-spacing:.08em}
.pptv-parse-sub{font-size:11.5px;color:rgba(207,200,184,.55);margin-top:10px;line-height:1.9}
/* 渲染结果：屏外幻灯片跳过绘制，滚动更顺滑 */
#pptvStage .slide{content-visibility:auto}

@media(max-width:900px){
  .pptv-bar{gap:7px;padding:0 8px}
  .pptv-name{max-width:22vw}
  .pptv-hint{display:none}
  .pptv-close{padding:0 9px}
  .pptv-counter{min-width:50px}
}

/* 自研 PPTX 渲染器输出的幻灯片 */
#pptvStage .slide{position:relative;flex:0 0 auto;box-sizing:border-box;font-family:"Microsoft YaHei","PingFang SC","Noto Sans SC",sans-serif}
#pptvStage .ps-el{box-sizing:border-box;overflow:hidden}
#pptvStage .ps-tx p,#pptvStage td p{white-space:pre-wrap;word-break:break-word}
#pptvStage .ps-el table td{border:1px solid rgba(0,0,0,.15)}
#pptvStage .ps-ph{width:100%;height:100%;display:flex;align-items:center;justify-content:center;background:rgba(0,0,0,.05);color:#98918a;font-size:13px;text-align:center}


/* 演示窗口底部备用入口（固定在窗口底部，任何渲染方式下都可见可点） */
.pptv-fallback{position:fixed;left:0;right:0;bottom:0;z-index:20;display:flex;gap:10px;align-items:center;justify-content:center;flex-wrap:wrap;padding:12px 18px 14px;background:linear-gradient(180deg,rgba(22,20,18,0),rgba(22,20,18,.94) 45%);color:rgba(236,229,214,.75);font-size:12.5px;letter-spacing:.03em}
.pptv-fallback .btn{height:30px;padding:0 14px;font-size:12px}

/* PDF 内置引擎渲染出的画布页 */
#pptvStage .pdf-page{display:block;flex:0 0 auto}

/* 环境自检列表 */
.env-list{display:flex;flex-direction:column;gap:7px}
.env-row{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:9px 12px;border:1px solid var(--line);border-radius:9px;font-size:13px;background:rgba(255,255,255,.5)}
.env-row b{font-weight:600}
.env-row b.ok{color:var(--jade)}
.env-row b.bad{color:var(--cinnabar)}

/* 预览环境提示条 */
.env-banner{position:fixed;left:0;right:0;bottom:0;z-index:900;display:flex;align-items:center;justify-content:center;gap:14px;flex-wrap:wrap;padding:10px 16px;background:#fdf3e6;border-top:1px solid #e6d5bb;color:#7a5c3e;font-size:12.5px;letter-spacing:.03em;box-shadow:0 -4px 18px rgba(0,0,0,.06)}
.env-banner b{color:#9c3125}
.env-banner button{border:1px solid #d9c4a3;background:#fff;color:#7a5c3e;border-radius:7px;padding:4px 12px;font-size:12px;cursor:pointer}

/* =========================================================
   成都树德中学校头 / 本机账号
   ========================================================= */
.brand-school{font-size:9px;letter-spacing:.16em;color:rgba(255,255,255,.38);white-space:nowrap}
.school-masthead{display:flex;align-items:center;gap:7px;margin-bottom:5px;color:var(--cinnabar);font-size:12px;letter-spacing:.14em}
.school-logo{width:22px;height:22px;border-radius:6px;display:grid;place-items:center;background:linear-gradient(145deg,#c74635,#9d2b23);color:#fff;font-family:var(--serif);font-size:14px;box-shadow:0 4px 12px rgba(176,57,45,.18)}
.account-chip{height:42px;padding:0 11px 0 6px;border-radius:12px;border:1px solid var(--line);display:flex;align-items:center;gap:7px;background:rgba(255,255,255,.55);color:var(--ink-2)}
.account-chip:hover{border-color:var(--line-2);background:var(--paper-2)}
.account-chip span{width:29px;height:29px;border-radius:9px;display:grid;place-items:center;background:var(--ink);color:#fff;font-size:12px}
.account-chip b{font-size:11px;font-weight:600;white-space:nowrap;max-width:74px;overflow:hidden;text-overflow:ellipsis}

.login-mask{position:fixed;inset:0;z-index:3000;display:grid;place-items:center;padding:24px;background:radial-gradient(circle at 70% 20%,rgba(176,57,45,.10),transparent 34%),#f3eee4}
.login-card{width:min(440px,100%);border:1px solid rgba(97,82,62,.15);border-radius:24px;background:rgba(255,253,247,.96);box-shadow:0 28px 80px rgba(46,39,31,.18);padding:34px}
.login-brand{display:flex;align-items:center;gap:14px;margin-bottom:26px}
.login-brand .school-logo{width:48px;height:48px;border-radius:13px;font-size:25px}
.login-brand h2{font-family:var(--serif);font-size:24px;letter-spacing:.08em}
.login-brand p{font-size:11px;color:var(--ink-3);margin-top:3px;letter-spacing:.12em}
.login-tabs{display:grid;grid-template-columns:1fr 1fr;background:var(--paper-3);border-radius:10px;padding:4px;margin-bottom:18px}
.login-tabs button{height:36px;border-radius:8px;color:var(--ink-3);font-size:12px}
.login-tabs button.is-active{background:#fff;color:var(--ink);box-shadow:0 3px 12px rgba(0,0,0,.06)}
.login-fields{display:flex;flex-direction:column;gap:12px}
.login-fields input{height:44px;width:100%;border-radius:10px}
.login-submit{height:44px;margin-top:4px;border-radius:10px;background:var(--ink);color:#fff;font-size:13px;letter-spacing:.08em}
.login-submit:hover{background:#2b3038}
.login-hint{font-size:11px;color:var(--ink-3);line-height:1.8;margin-top:14px;text-align:center}
.account-list{display:flex;flex-direction:column;gap:8px;margin-top:10px}
.account-row{display:flex;align-items:center;gap:10px;padding:10px 12px;border:1px solid var(--line);border-radius:10px;background:rgba(255,255,255,.5)}
.account-row b{font-size:13px}.account-row span{font-size:11px;color:var(--ink-3)}.account-row .spacer{flex:1}

/* 学生账号：课程与概念可读，个人错题可写，教师管理入口隐藏。 */
body.role-student #btnSettings,
body.role-student .teacher-only,
body.role-student .rail-btn[data-view="tools"],
body.role-student #btnNewConcept,
body.role-student #btnConceptCapture,
body.role-student #btnAddSlide,
body.role-student #btnImportConcept,
body.role-student .deck-meta,
body.role-student #dropZone,
body.role-student #btnSetCurrent,
body.role-student #btnClearFiles,
body.role-student .file-actions .danger,
body.role-student .slide-actions,
body.role-student #cdEdit,
body.role-student #cdDel,
body.role-student #cdSlide,
body.role-student #cdFav,
body.role-student .fav-btn{display:none!important}

/* =========================================================
   作业中心 / 班级管理
   ========================================================= */
.homework-stats{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px;margin-bottom:18px}
.hw-stat{padding:18px 20px;border:1px solid var(--line);border-radius:15px;background:rgba(255,253,247,.76);box-shadow:var(--shadow-sm)}
.hw-stat span{display:block;font-size:11px;color:var(--ink-3);letter-spacing:.08em}.hw-stat b{display:block;font-family:var(--serif);font-size:28px;line-height:1.25;margin-top:4px}.hw-stat em{font-style:normal;font-size:11px;color:var(--cinnabar);margin-left:4px}
.homework-list{display:flex;flex-direction:column;gap:14px}
.homework-card{border:1px solid var(--line);border-radius:17px;background:rgba(255,253,247,.78);padding:20px 22px;box-shadow:var(--shadow-sm)}
.homework-card-head{display:flex;align-items:flex-start;gap:16px}.homework-card-head>div:first-child{min-width:0;flex:1}
.homework-title{font-family:var(--serif);font-size:21px;line-height:1.35}.homework-meta{display:flex;gap:8px;align-items:center;flex-wrap:wrap;margin-top:7px;color:var(--ink-3);font-size:11px}
.homework-desc{margin-top:12px;color:var(--ink-2);white-space:pre-wrap}.homework-progress{margin-top:16px;display:flex;align-items:center;gap:12px}.homework-progress-track{height:7px;border-radius:99px;background:var(--paper-3);overflow:hidden;flex:1}.homework-progress-track i{display:block;height:100%;border-radius:inherit;background:linear-gradient(90deg,var(--cinnabar),var(--gold))}.homework-progress b{font-size:11px;color:var(--ink-3);min-width:72px;text-align:right}
.homework-actions{display:flex;gap:8px;flex-wrap:wrap;margin-top:16px}.homework-actions .btn{height:34px}
.submission-list{display:flex;flex-direction:column;gap:8px;margin-top:14px}.submission-row{display:grid;grid-template-columns:minmax(120px,1fr) minmax(180px,1.5fr) 90px minmax(120px,1fr) auto;align-items:center;gap:10px;padding:11px 12px;border:1px solid var(--line);border-radius:11px;background:rgba(255,255,255,.52)}
.submission-row .sub-name{font-weight:600}.submission-row .sub-file{min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;color:var(--ink-2);font-size:12px}.submission-row .sub-state{font-size:11px;color:var(--jade)}.submission-row .sub-state.pending{color:var(--gold)}.submission-row .sub-comment{font-size:11px;color:var(--ink-3);overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.class-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.class-card{border:1px solid var(--line);border-radius:17px;background:rgba(255,253,247,.78);padding:21px;box-shadow:var(--shadow-sm)}.class-card h3{font-family:var(--serif);font-size:22px}.class-card .class-meta{font-size:11px;color:var(--ink-3);margin-top:4px}.class-card .class-members{margin-top:15px;display:flex;flex-wrap:wrap;gap:6px;min-height:28px}.class-member{padding:4px 9px;border-radius:99px;background:var(--paper-3);font-size:11px;color:var(--ink-2)}.class-card .homework-actions{margin-top:18px}
.assignment-upload{border:1px dashed rgba(176,57,45,.35);background:var(--cinnabar-soft);border-radius:13px;padding:18px;text-align:center;margin-top:14px}.assignment-upload input{display:none}.assignment-upload p{font-size:12px;color:var(--ink-3);margin-bottom:10px}

@media (max-width:1000px){.homework-stats{grid-template-columns:repeat(2,1fr)}.class-grid{grid-template-columns:repeat(2,1fr)}.submission-row{grid-template-columns:1fr 1.4fr auto}.submission-row .sub-comment,.submission-row .sub-state{display:none}}
@media (max-width:650px){.homework-stats,.class-grid{grid-template-columns:1fr}.submission-row{grid-template-columns:1fr auto}.submission-row .sub-file{display:none}}

/* =========================================================
   截图收录 / 图片卡片
   ========================================================= */
.capture-preview{border:1px solid var(--line);border-radius:14px;background:#17191e;padding:10px;display:grid;place-items:center;min-height:180px;overflow:hidden}
.capture-preview img{display:block;max-width:100%;max-height:360px;border-radius:7px;box-shadow:0 8px 30px rgba(0,0,0,.25)}
.capture-actions{display:flex;gap:10px;flex-wrap:wrap;margin-top:12px}
.capture-note{font-size:11px;color:var(--ink-3);line-height:1.7;margin-top:8px}
.record-capture{margin-top:11px;border-radius:9px;overflow:hidden;border:1px solid var(--line);background:#14161a;max-height:190px}
.record-capture img{width:100%;height:100%;max-height:190px;object-fit:contain;display:block}
.ocr-badge{display:inline-flex;align-items:center;gap:5px;padding:3px 7px;border-radius:99px;background:var(--jade-soft);color:var(--jade);font-size:10px;margin-left:6px}

/* =========================================================
   类希沃演示批注工具箱
   ========================================================= */
.teach-toolbox{position:fixed;z-index:1210;left:50%;bottom:28px;transform:translateX(-50%);display:none;align-items:center;gap:6px;padding:7px;border-radius:14px;background:rgba(27,30,36,.95);border:1px solid rgba(255,255,255,.13);box-shadow:0 16px 46px rgba(0,0,0,.45);backdrop-filter:blur(16px)}
body.has-env-banner .teach-toolbox{bottom:78px}
.teach-toolbox.is-open{display:flex}
.teach-toolbox button{width:36px;height:36px;border-radius:9px;color:#eee7d8;font-size:14px;display:grid;place-items:center}
.teach-toolbox button:hover,.teach-toolbox button.is-active{background:rgba(255,255,255,.13)}
.teach-toolbox .tool-color{width:22px;height:22px;border-radius:50%;background:#e64235;border:2px solid transparent;margin:0 2px}
.teach-toolbox .tool-color.gold{background:#f2bd43}.teach-toolbox .tool-color.blue{background:#2563eb}
.teach-toolbox .tool-color.is-active{border-color:#fff;box-shadow:0 0 0 2px rgba(255,255,255,.18)}
.ink-canvas{position:fixed;inset:0;width:100%;height:100%;z-index:1190;pointer-events:none;touch-action:none}
.ink-canvas.is-drawing{pointer-events:auto;cursor:crosshair}
.board-layer{position:fixed;inset:0;z-index:1170;display:none;background:rgba(15,18,22,.94);pointer-events:none}
.board-layer.is-open{display:block}
.board-hint{position:absolute;top:70px;left:50%;transform:translateX(-50%);color:rgba(255,255,255,.28);font-size:11px;letter-spacing:.16em}

@media (max-width:900px){
  .school-masthead b,.account-chip b,.brand-school{display:none}
  .account-chip{padding-right:6px}
  .teach-toolbox{bottom:14px;max-width:calc(100vw - 20px);overflow-x:auto}
}