:root{
  --bg:#f6f1e7; --bg2:#fffdf8; --card:#fffdf9; --card2:#faf5ea;
  --ink:#211c16; --ink2:#4a4339; --muted:#8b8274; --line:rgba(33,28,22,.09);
  --accent:#ac3b2a; --accent2:#c9603f; --accent-soft:#f6e2db; --accent-ink:#8d2f22;
  --gold:#b8873f; --gold-soft:#f6ecd8;
  --ok:#2f7d5b; --ok-soft:#e2f0e9; --bad:#c23b2e; --bad-soft:#f9e4e0;
  --shadow:0 1px 2px rgba(40,30,20,.04),0 8px 24px -12px rgba(60,40,20,.16);
  --shadow-lg:0 2px 6px rgba(40,30,20,.06),0 24px 60px -24px rgba(60,40,20,.28);
  --r-s:12px; --r:18px; --r-l:26px;
  --sans:-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --serif:"Songti SC","STSong","Noto Serif SC",Georgia,serif;
  --tab-h:64px;
}
html[data-theme="dark"]{
  --bg:#141210; --bg2:#1a1714; --card:#1e1a16; --card2:#241f1a;
  --ink:#f1eae0; --ink2:#cfc5b8; --muted:#9b9184; --line:rgba(241,234,224,.10);
  --accent:#e0755a; --accent2:#d98c6a; --accent-soft:#3a241d; --accent-ink:#f0b6a5;
  --gold:#d8a85e; --gold-soft:#332a1c;
  --ok:#66b58d; --ok-soft:#1e3329; --bad:#e0796c; --bad-soft:#3a221d;
  --shadow:0 1px 2px rgba(0,0,0,.4),0 10px 26px -14px rgba(0,0,0,.7);
  --shadow-lg:0 2px 8px rgba(0,0,0,.45),0 30px 70px -30px rgba(0,0,0,.85);
}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
[hidden]{display:none!important}
html,body{margin:0;padding:0}
html{-webkit-text-size-adjust:100%}
body{
  font-family:var(--sans); background:var(--bg); color:var(--ink);
  font-size:16px; line-height:1.6; letter-spacing:.01em;
  overscroll-behavior-y:none; min-height:100vh;
}
body::before{
  content:""; position:fixed; inset:0; pointer-events:none; z-index:0;
  background:
    radial-gradient(1200px 600px at 15% -10%, rgba(184,135,63,.10), transparent 60%),
    radial-gradient(900px 500px at 110% 0%, rgba(172,59,42,.07), transparent 60%);
}
button,a{font-family:inherit;color:inherit}
h1,h2,h3,h4,p{margin:0}
input,textarea,select{font-family:inherit;font-size:16px;color:inherit}
a{text-decoration:none}

/* ---------- boot ---------- */
.boot{position:fixed;inset:0;display:grid;place-content:center;justify-items:center;gap:8px;background:var(--bg);z-index:100}
.boot-logo{font-family:var(--serif);font-size:44px;letter-spacing:.18em;color:var(--accent);text-indent:.18em}
.boot-sub{color:var(--muted);letter-spacing:.28em;font-size:12px;text-indent:.28em}
.boot-bar{width:120px;height:2px;background:var(--line);margin-top:18px;overflow:hidden;border-radius:2px}
.boot-bar i{display:block;height:100%;width:40%;background:var(--accent);animation:bootSlide 1s ease-in-out infinite}
@keyframes bootSlide{0%{transform:translateX(-100%)}100%{transform:translateX(320%)}}

/* ---------- shell ---------- */
.app{position:relative;z-index:1;max-width:1120px;margin:0 auto;min-height:100vh;display:flex;flex-direction:column}
.topbar{
  position:sticky;top:0;z-index:30;display:flex;align-items:center;justify-content:space-between;
  padding:calc(env(safe-area-inset-top) + 10px) 18px 10px;
  background:color-mix(in srgb,var(--bg) 82%,transparent);
  backdrop-filter:saturate(1.4) blur(18px); -webkit-backdrop-filter:saturate(1.4) blur(18px);
  border-bottom:1px solid transparent; transition:border-color .2s;
}
.app.scrolled .topbar{border-bottom-color:var(--line)}
.topbar-left,.topbar-right{display:flex;align-items:center;gap:10px}
.brand{display:flex;align-items:baseline;gap:8px}
.brand-mark{font-family:var(--serif);font-size:22px;font-weight:600;color:var(--accent);letter-spacing:.12em}
.brand-text{font-size:12px;letter-spacing:.3em;color:var(--muted)}
.icon-btn{
  width:44px;height:44px;border-radius:50%;border:1px solid var(--line);background:var(--card);
  display:grid;place-items:center;font-size:18px;color:var(--ink2);cursor:pointer;
  transition:transform .16s ease, background .2s;
}
.icon-btn:active{transform:scale(.94)}
.icon-btn#backBtn{font-size:26px;line-height:1;padding-bottom:4px}
.avatar{
  width:42px;height:42px;border-radius:50%;border:1px solid var(--line);
  background:linear-gradient(145deg,var(--accent-soft),var(--gold-soft));color:var(--accent-ink);
  font-family:var(--serif);font-size:17px;cursor:pointer;
}
.main{flex:1;padding:6px 18px calc(var(--tab-h) + env(safe-area-inset-bottom) + 26px);outline:none}

/* ---------- tabbar ---------- */
.tabbar{
  position:fixed;left:50%;transform:translateX(-50%);bottom:0;z-index:40;
  width:min(1120px,100%); display:grid;grid-template-columns:repeat(5,1fr);
  padding:6px 8px calc(env(safe-area-inset-bottom) + 6px);
  background:color-mix(in srgb,var(--bg2) 86%,transparent);
  backdrop-filter:saturate(1.5) blur(22px);-webkit-backdrop-filter:saturate(1.5) blur(22px);
  border-top:1px solid var(--line);
}
.tab{display:grid;justify-items:center;gap:2px;padding:6px 0;border-radius:14px;color:var(--muted);font-size:11px;letter-spacing:.06em;transition:color .2s,background .2s;cursor:pointer}
.tab-ico{font-size:20px;line-height:1.1}
.tab.active{color:var(--accent)}
.tab.active .tab-ico{transform:translateY(-1px)}
.tab:active{background:var(--accent-soft)}

/* ---------- common ---------- */
.view{animation:viewIn .32s cubic-bezier(.22,.8,.3,1)}
@keyframes viewIn{from{opacity:0;transform:translateY(10px)}to{opacity:1;transform:none}}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--r);box-shadow:var(--shadow)}
.section{margin:26px 0 10px;display:flex;align-items:baseline;justify-content:space-between;gap:12px}
.section h2{font-size:17px;font-weight:650;letter-spacing:.02em}
.section .link{font-size:13px;color:var(--accent);cursor:pointer}
.muted{color:var(--muted)}
.small{font-size:13px}
.tiny{font-size:12px}
.serif{font-family:var(--serif)}
.center{text-align:center}

.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  min-height:48px;padding:0 20px;border-radius:999px;border:1px solid transparent;
  background:var(--accent);color:#fff;font-size:15px;font-weight:600;letter-spacing:.04em;
  cursor:pointer;transition:transform .14s ease,filter .2s,background .2s;
}
.btn:active{transform:scale(.97)}
.btn.block{width:100%}
.btn.ghost{background:transparent;color:var(--ink2);border-color:var(--line)}
.btn.soft{background:var(--accent-soft);color:var(--accent-ink);border-color:transparent}
.btn.gold{background:linear-gradient(135deg,var(--gold),#a4762f);color:#fff}
.btn[disabled]{opacity:.45;pointer-events:none}
.btn.lg{min-height:54px;font-size:16px;padding:0 26px}

.chip{
  display:inline-flex;align-items:center;gap:6px;height:32px;padding:0 13px;border-radius:999px;
  background:var(--card2);border:1px solid var(--line);color:var(--ink2);font-size:13px;cursor:pointer;
  white-space:nowrap;transition:all .18s;
}
.chip.active{background:var(--accent);color:#fff;border-color:transparent}
.chip:active{transform:scale(.96)}
.chips{display:flex;gap:8px;overflow-x:auto;padding:2px;scrollbar-width:none}
.chips::-webkit-scrollbar{display:none}

.tag{display:inline-flex;align-items:center;height:24px;padding:0 9px;border-radius:7px;font-size:11.5px;letter-spacing:.04em;background:var(--gold-soft);color:#8a6524}
html[data-theme="dark"] .tag{color:var(--gold)}
.tag.red{background:var(--accent-soft);color:var(--accent-ink)}
.tag.green{background:var(--ok-soft);color:var(--ok)}

.grid{display:grid;gap:14px}
.g2{grid-template-columns:repeat(2,1fr)}
.g3{grid-template-columns:repeat(3,1fr)}
@media(min-width:820px){.g3{grid-template-columns:repeat(3,1fr)}}
@media(max-width:520px){.g3{grid-template-columns:1fr 1fr}}

/* ---------- hero / dashboard ---------- */
.hero{padding:22px 20px;border-radius:var(--r-l);position:relative;overflow:hidden;
  background:linear-gradient(150deg,#fffdf9,var(--card2));border:1px solid var(--line);box-shadow:var(--shadow)}
html[data-theme="dark"] .hero{background:linear-gradient(150deg,#211c17,#1a1713)}
.hero::after{content:"";position:absolute;right:-40px;top:-60px;width:220px;height:220px;border-radius:50%;
  background:radial-gradient(circle,rgba(172,59,42,.16),transparent 68%)}
.hero-top{display:flex;justify-content:space-between;align-items:flex-start;gap:16px;position:relative}
.hero h1{font-family:var(--serif);font-size:26px;line-height:1.3;letter-spacing:.02em}
.hero p{color:var(--muted);font-size:13.5px;margin-top:6px}
.countdown{text-align:right;flex-shrink:0}
.countdown b{font-family:var(--serif);font-size:38px;line-height:1;color:var(--accent);font-weight:600}
.countdown span{display:block;font-size:11px;color:var(--muted);letter-spacing:.16em;margin-top:4px}
.hero-stats{display:flex;gap:22px;margin-top:20px;position:relative}
.hero-stat b{font-size:20px;font-weight:650}
.hero-stat span{display:block;font-size:11.5px;color:var(--muted);letter-spacing:.08em}

.ring-wrap{display:flex;align-items:center;gap:20px;padding:20px}
.ring{--p:0;width:104px;height:104px;border-radius:50%;flex-shrink:0;display:grid;place-items:center;position:relative;
  background:conic-gradient(var(--accent) calc(var(--p)*1%),var(--line) 0)}
.ring::before{content:"";position:absolute;inset:9px;border-radius:50%;background:var(--card)}
.ring b{position:relative;font-family:var(--serif);font-size:26px}
.ring b i{font-style:normal;font-size:12px;color:var(--muted);margin-left:1px}
.ring-info h3{font-size:16px;margin-bottom:4px}
.ring-info p{font-size:13px;color:var(--muted)}

.quick{display:grid;grid-template-columns:repeat(4,1fr);gap:10px}
@media(max-width:520px){.quick{grid-template-columns:repeat(4,1fr);gap:8px}}
.quick-btn{
  display:grid;justify-items:center;gap:7px;padding:14px 6px;border-radius:var(--r);
  background:var(--card);border:1px solid var(--line);cursor:pointer;transition:transform .16s,box-shadow .2s;
}
.quick-btn:active{transform:scale(.96)}
.quick-btn .qi{width:40px;height:40px;border-radius:13px;display:grid;place-items:center;font-size:19px;background:var(--accent-soft);color:var(--accent-ink)}
.quick-btn span{font-size:12px;color:var(--ink2)}
.quick-btn.g .qi{background:var(--gold-soft);color:#8a6524}
.quick-btn.o .qi{background:var(--ok-soft);color:var(--ok)}

.subject-row{display:flex;align-items:center;gap:14px;padding:15px 16px;border-radius:var(--r);background:var(--card);border:1px solid var(--line);cursor:pointer;transition:transform .16s}
.subject-row:active{transform:scale(.985)}
.subject-badge{width:50px;height:50px;border-radius:15px;display:grid;place-items:center;font-family:var(--serif);font-size:12px;line-height:1.1;letter-spacing:-.02em;flex-shrink:0;text-align:center;padding:0;white-space:nowrap}
.subject-main{flex:1;min-width:0}
.subject-main b{font-size:15px;font-weight:600;display:block}
.subject-main span{font-size:12px;color:var(--muted)}
.bar{height:6px;border-radius:99px;background:var(--line);overflow:hidden;margin-top:7px}
.bar i{display:block;height:100%;border-radius:99px;background:linear-gradient(90deg,var(--accent),var(--accent2));transition:width .6s cubic-bezier(.2,.8,.2,1)}

/* ---------- practice ---------- */
.prac-head{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:10px 2px 14px}
.prac-head .pnum{font-family:var(--serif);font-size:15px;color:var(--muted)}
.prac-head .pnum b{color:var(--ink);font-size:18px}
.qcard{padding:20px 20px 18px;border-radius:var(--r-l);background:var(--card);border:1px solid var(--line);box-shadow:var(--shadow);animation:viewIn .28s}
.qmeta{display:flex;align-items:center;gap:8px;flex-wrap:wrap;margin-bottom:12px}
.qstem{font-size:17px;line-height:1.85;letter-spacing:.01em;white-space:pre-wrap}
.qstem::first-letter{}
.material{padding:12px 14px;border-left:3px solid var(--gold);background:var(--gold-soft);border-radius:0 12px 12px 0;font-size:14.5px;line-height:1.8;margin:12px 0;color:var(--ink2)}
.opts{display:grid;gap:10px;margin-top:18px}
.opt{
  display:flex;gap:12px;align-items:flex-start;padding:14px 15px;border-radius:16px;
  border:1.5px solid var(--line);background:var(--card);cursor:pointer;
  transition:border-color .18s,background .18s,transform .12s; min-height:56px;
}
.opt:active{transform:scale(.993)}
.opt .k{
  width:26px;height:26px;border-radius:50%;flex-shrink:0;display:grid;place-items:center;
  border:1.5px solid var(--line);font-size:13px;font-weight:600;color:var(--muted);background:var(--card2);
  transition:all .18s;
}
.opt .v{font-size:15.5px;line-height:1.7;padding-top:1px;white-space:pre-wrap}
.opt.sel{border-color:var(--accent);background:var(--accent-soft)}
.opt.sel .k{background:var(--accent);border-color:var(--accent);color:#fff}
.opt.ok{border-color:var(--ok);background:var(--ok-soft)}
.opt.ok .k{background:var(--ok);border-color:var(--ok);color:#fff}
.opt.bad{border-color:var(--bad);background:var(--bad-soft)}
.opt.bad .k{background:var(--bad);border-color:var(--bad);color:#fff}
.opt.dim{opacity:.55}

.acts{display:flex;gap:10px;margin-top:18px;align-items:center}
.acts .btn{flex:1}
.acts .icon-btn{flex:0 0 48px;width:48px;height:48px}

.explain{margin-top:18px;border-top:1px dashed var(--line);padding-top:16px;animation:viewIn .3s}
.explain .verdict{display:flex;align-items:center;gap:10px;font-size:15px;font-weight:650}
.verdict .dot{width:10px;height:10px;border-radius:50%;background:var(--ok)}
.verdict.fail .dot{background:var(--bad)}
.explain p{font-size:14.5px;line-height:1.85;color:var(--ink2);margin-top:8px}
.opt-note{display:flex;gap:10px;padding:9px 0;border-bottom:1px dashed var(--line);font-size:13.5px;line-height:1.7}
.opt-note:last-child{border-bottom:0}
.opt-note b{color:var(--accent);flex-shrink:0;width:18px}
.opt-note.correct b{color:var(--ok)}
.kp{margin-top:10px;display:flex;gap:12px;flex-wrap:wrap;font-size:13px;color:var(--muted)}
.kp b{color:var(--ink2);font-weight:600}

/* ---------- list rows ---------- */
.row{display:flex;align-items:center;gap:12px;padding:14px 16px;background:var(--card);border:1px solid var(--line);border-radius:var(--r);cursor:pointer;transition:transform .15s}
.row:active{transform:scale(.99)}
.row .grow{flex:1;min-width:0}
.row b{display:block;font-size:14.5px;font-weight:600;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.row span{font-size:12px;color:var(--muted)}
.row .arrow{color:var(--muted);font-size:18px}
.list{display:grid;gap:10px}

/* ---------- cards ---------- */
.kcard{perspective:1400px;cursor:pointer;height:300px}
.kcard-inner{position:relative;width:100%;height:100%;transition:transform .55s cubic-bezier(.4,.1,.2,1);transform-style:preserve-3d}
.kcard.flip .kcard-inner{transform:rotateY(180deg)}
.kface{position:absolute;inset:0;backface-visibility:hidden;-webkit-backface-visibility:hidden;border-radius:var(--r-l);
  border:1px solid var(--line);background:var(--card);box-shadow:var(--shadow);padding:20px;display:flex;flex-direction:column;overflow:auto}
.kface.back{transform:rotateY(180deg);background:linear-gradient(160deg,var(--card),var(--card2))}
.kface h3{font-family:var(--serif);font-size:21px;line-height:1.5;margin-top:12px}
.kface .q{font-size:17px;color:var(--ink2);margin-top:16px;line-height:1.8;font-family:var(--serif)}
.kface .body{font-size:14.5px;line-height:1.9;margin-top:12px;color:var(--ink2);white-space:pre-wrap}
.kface .foot{margin-top:auto;padding-top:12px;display:flex;justify-content:space-between;align-items:center;font-size:12px;color:var(--muted)}

/* ---------- exam ---------- */
.exam-bar{position:sticky;top:64px;z-index:20;display:flex;align-items:center;gap:12px;padding:10px 14px;border-radius:14px;
  background:color-mix(in srgb,var(--card) 92%,transparent);border:1px solid var(--line);backdrop-filter:blur(12px)}
.timer{font-variant-numeric:tabular-nums;font-family:var(--serif);font-size:18px}
.timer.warn{color:var(--bad)}
.sheetgrid{display:grid;grid-template-columns:repeat(auto-fill,minmax(42px,1fr));gap:8px;margin-top:6px}
.sheetgrid button{height:42px;border-radius:11px;border:1px solid var(--line);background:var(--card);font-size:13px;cursor:pointer}
.sheetgrid button.done{background:var(--accent-soft);border-color:transparent;color:var(--accent-ink)}
.sheetgrid button.cur{outline:2px solid var(--accent);outline-offset:1px}

/* ---------- stats ---------- */
.stat-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px}
.stat{padding:16px;border-radius:var(--r);background:var(--card);border:1px solid var(--line)}
.stat b{font-family:var(--serif);font-size:26px;display:block;line-height:1.2}
.stat span{font-size:11.5px;color:var(--muted);letter-spacing:.1em}
.spark{display:flex;align-items:flex-end;gap:6px;height:96px;padding:10px 4px 0}
.spark i{flex:1;border-radius:6px 6px 3px 3px;background:linear-gradient(180deg,var(--accent2),var(--accent));min-height:4px;opacity:.85;transition:height .5s}

/* ---------- sheet / toast ---------- */
.sheet{position:fixed;inset:0;z-index:80;display:grid;align-items:end}
.sheet-mask{position:absolute;inset:0;background:rgba(20,15,10,.45);backdrop-filter:blur(3px);animation:fade .25s}
.sheet-body{position:relative;background:var(--bg2);border-radius:26px 26px 0 0;padding:22px 20px calc(env(safe-area-inset-bottom) + 22px);
  max-height:86vh;overflow:auto;animation:up .32s cubic-bezier(.2,.9,.3,1);box-shadow:var(--shadow-lg)}
.sheet-body h3{font-family:var(--serif);font-size:20px;margin-bottom:6px}
@keyframes fade{from{opacity:0}}
@keyframes up{from{transform:translateY(24px);opacity:.6}}
.toast{position:fixed;left:50%;bottom:calc(var(--tab-h) + 30px);transform:translateX(-50%);z-index:90;
  background:var(--ink);color:var(--bg);padding:11px 20px;border-radius:999px;font-size:13.5px;box-shadow:var(--shadow-lg);animation:up .25s}

/* ---------- misc ---------- */
.empty{display:grid;justify-items:center;gap:8px;padding:60px 20px;color:var(--muted);font-size:14px}
.empty .e{font-size:38px;opacity:.5}
.seg{display:flex;background:var(--card2);border:1px solid var(--line);border-radius:12px;padding:3px;gap:2px}
.seg button{flex:1;border:0;background:transparent;height:38px;border-radius:9px;font-size:13.5px;color:var(--muted);cursor:pointer}
.seg button.on{background:var(--card);color:var(--ink);box-shadow:var(--shadow)}
.field{display:grid;gap:7px;margin:16px 0}
.field label{font-size:12.5px;color:var(--muted);letter-spacing:.06em}
.field input,.field select{height:48px;padding:0 14px;border-radius:13px;border:1px solid var(--line);background:var(--card);outline:none}
.field input:focus{border-color:var(--accent)}
.divider{height:1px;background:var(--line);margin:18px 0}
.mono{font-variant-numeric:tabular-nums}

@media(min-width:900px){
  .main{padding-left:28px;padding-right:28px}
  .qstem{font-size:18px}
}
@media(prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}}


.gate{position:fixed;inset:0;z-index:60;display:grid;place-items:center;padding:24px;background:var(--bg)}
.gate-box{width:min(360px,92vw);background:var(--card);border:1px solid var(--line);border-radius:var(--r-l);padding:26px 22px;box-shadow:var(--shadow-lg)}