/* ============ Reset & Tokens ============ */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  color-scheme:light;
  /* 字体：Inter 界面 / Instrument Serif 标题 / 明朝体日文 / ゴシック辅读 */
  --ui:"Inter","Noto Sans JP",-apple-system,BlinkMacSystemFont,"Segoe UI","Microsoft YaHei",sans-serif;
  --display:"Instrument Serif","Noto Serif JP","Hiragino Mincho ProN","Yu Mincho",serif;
  --jp:"Noto Serif JP","Hiragino Mincho ProN","Yu Mincho",serif;
  --jp-sans:"Noto Sans JP","Yu Gothic UI","Yu Gothic","Hiragino Kaku Gothic ProN",sans-serif;

  --bg:#f4f3f0;
  --surface:#ffffff;
  --surface-2:#faf9f6;
  --surface-solid:#ffffff;
  --line:rgba(24,22,18,.10);
  --line-soft:rgba(24,22,18,.06);
  --ink:#191813;
  --ink-2:#56534c;
  --ink-3:#8b877e;
  --muted:#857f76;
  --accent:#c4452f;
  --accent-2:#e0563c;
  --accent-soft:rgba(196,69,47,.09);
  --green:#3f7d5c;
  --green-soft:rgba(63,125,92,.09);
  --amber:#a8712a;
  --blue:#3c5f92;
  --radius:13px;
  --radius-lg:16px;
  --blur:none;
  --ambient:0;
  --shadow:0 1px 2px rgba(28,25,20,.04),0 8px 24px -14px rgba(28,25,20,.10);
  --shadow-lg:0 2px 4px rgba(28,25,20,.05),0 24px 48px -22px rgba(28,25,20,.16);
}
html[data-theme="dark"]{
  color-scheme:dark;
  --bg:#08080a;
  --surface:rgba(255,255,255,.045);
  --surface-2:rgba(255,255,255,.075);
  --surface-solid:#141417;
  --line:rgba(255,255,255,.10);
  --line-soft:rgba(255,255,255,.065);
  --ink:#f1efec;
  --ink-2:#a5a29e;
  --ink-3:#736f6b;
  --muted:#8b8783;
  --accent:#ff5c46;
  --accent-2:#ff8467;
  --accent-soft:rgba(255,92,70,.14);
  --green:#3ecf8e;
  --green-soft:rgba(62,207,142,.13);
  --amber:#f2b13c;
  --blue:#6aa3ff;
  --blur:blur(24px) saturate(180%);
  --ambient:1;
  --shadow:inset 0 1px 0 rgba(255,255,255,.055),0 12px 28px -14px rgba(0,0,0,.85);
  --shadow-lg:inset 0 1px 0 rgba(255,255,255,.07),0 28px 60px -24px rgba(0,0,0,.9);
}
html,body{height:100%}
body{
  background:var(--bg);color:var(--ink);font-family:var(--ui);
  font-size:15px;line-height:1.6;-webkit-font-smoothing:antialiased;
  overflow:hidden;
}
/* 环境光晕：让毛玻璃有内容可折射 */
body::before{
  content:"";position:fixed;inset:0;z-index:0;pointer-events:none;opacity:var(--ambient);
  background:
    radial-gradient(900px 620px at 10% -12%, rgba(255,92,70,.13), transparent 60%),
    radial-gradient(820px 520px at 94% 6%, rgba(106,163,255,.09), transparent 62%),
    radial-gradient(1000px 700px at 50% 112%, rgba(255,92,70,.07), transparent 60%);
}
::selection{background:rgba(255,92,70,.28);color:var(--ink)}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:6px}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer;background:none;border:none}
::-webkit-scrollbar{width:10px;height:10px}
::-webkit-scrollbar-thumb{background:var(--line);border-radius:10px;border:3px solid transparent;background-clip:content-box}
::-webkit-scrollbar-thumb:hover{background:var(--ink-3);background-clip:content-box}
::-webkit-scrollbar-track{background:transparent}

/* ============ Layout ============ */
.app{display:flex;height:100vh;overflow:hidden;position:relative;z-index:1}
.sidebar{
  width:250px;flex:0 0 250px;background:var(--surface);
  -webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  border-right:1px solid var(--line);display:flex;flex-direction:column;
  padding:24px 16px 16px;position:relative;z-index:2;
}
html[data-theme="dark"] .sidebar{
  background:linear-gradient(180deg,rgba(22,22,26,.80),rgba(10,10,13,.88));
}
.main{flex:1;overflow-y:auto;position:relative;scroll-behavior:smooth;z-index:1}

/* ============ Brand ============ */
.brand{display:flex;gap:12px;align-items:center;padding:0 8px 26px}
.brand-mark{
  width:40px;height:40px;flex:0 0 40px;border-radius:12px;
  background:linear-gradient(145deg,var(--accent-2) 0%,#cf3520 100%);color:#fff;
  display:grid;place-items:center;font-family:var(--jp);font-size:21px;font-weight:600;
  box-shadow:0 8px 20px -8px rgba(255,92,70,.65),inset 0 1px 0 rgba(255,255,255,.28);
}
html[data-theme="dark"] .brand-mark{box-shadow:0 8px 22px -8px rgba(255,92,70,.85),inset 0 1px 0 rgba(255,255,255,.3)}
.brand-title{font-family:var(--ui);font-weight:600;font-size:14.5px;letter-spacing:-.005em}
.brand-sub{font-size:11px;color:var(--ink-3);letter-spacing:.14em;margin-top:2px;text-transform:uppercase;font-weight:500}

/* ============ Nav ============ */
.nav{display:flex;flex-direction:column;gap:2px}
.nav-item{
  display:flex;align-items:center;gap:10px;padding:9px 12px;border-radius:9px;
  color:var(--ink-2);font-size:13.5px;text-align:left;
  transition:background .16s ease,color .16s ease,transform .16s ease;
  position:relative;font-weight:450;
}
.nav-item .ni{width:16px;text-align:center;font-size:13px;opacity:.55;flex:0 0 16px}
.nav-item:hover{background:var(--surface-2);color:var(--ink)}
.nav-item.active{
  color:var(--accent);font-weight:600;
  background:linear-gradient(90deg,var(--accent-soft),transparent 92%);
}
.nav-item.active .ni{opacity:1}
.nav-item.active::before{
  content:"";position:absolute;left:0;top:50%;transform:translateY(-50%);
  width:2px;height:16px;border-radius:0 2px 2px 0;background:var(--accent);
  box-shadow:0 0 10px var(--accent);
}
html[data-theme="dark"] .nav-item.active{box-shadow:inset 0 0 0 1px rgba(255,92,70,.10)}
.badge{
  margin-left:auto;background:var(--accent);color:#fff;font-size:10.5px;font-weight:600;
  min-width:20px;height:19px;border-radius:10px;display:grid;place-items:center;padding:0 6px;
  font-variant-numeric:tabular-nums;letter-spacing:.02em;
}
html[data-theme="dark"] .badge{box-shadow:0 2px 10px -3px rgba(255,92,70,.7)}

.sidebar-foot{margin-top:auto;padding-top:20px;display:flex;flex-direction:column;gap:16px}
.streak{display:flex;align-items:baseline;gap:8px;padding:0 12px}
.streak-num{
  font-size:28px;font-weight:600;line-height:1;font-variant-numeric:tabular-nums;
  letter-spacing:-.02em;
}
.streak-lbl{font-size:11px;color:var(--ink-3);letter-spacing:.12em;text-transform:uppercase}
.level-switch{display:grid;grid-template-columns:repeat(3,1fr);gap:5px;padding:0 4px}
.lv{
  padding:7px 0;border-radius:9px;border:1px solid var(--line-soft);
  font-size:12.5px;color:var(--ink-2);font-weight:500;letter-spacing:.02em;
  transition:all .16s ease;background:var(--surface-2);font-variant-numeric:tabular-nums;
}
.lv.wide{grid-column:span 3}
.lv:hover{border-color:var(--line);color:var(--ink)}
.lv.active{
  background:linear-gradient(160deg,var(--accent-2),#cf3520);color:#fff;border-color:transparent;
  box-shadow:0 6px 16px -8px rgba(255,92,70,.75),inset 0 1px 0 rgba(255,255,255,.22);font-weight:600;
}

/* ============ Views ============ */
.view{display:none;padding:40px 48px 64px;max-width:1080px;margin:0 auto;animation:fade .3s cubic-bezier(.2,.8,.3,1)}
.view.active{display:block}
@keyframes fade{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}

/* ============ Hero ============ */
.hero{display:flex;justify-content:space-between;align-items:center;gap:32px;margin-bottom:32px}
.hero-eyebrow{
  font-size:11px;letter-spacing:.18em;text-transform:uppercase;color:var(--accent);
  margin-bottom:10px;font-weight:600;
}
html[data-theme="dark"] .hero-eyebrow{text-shadow:0 0 18px rgba(255,92,70,.45)}
.hero-title{
  font-family:var(--display);font-size:42px;font-weight:400;letter-spacing:.005em;line-height:1.15;
}
.hero-desc{color:var(--ink-2);margin-top:10px;font-size:14.5px;max-width:460px;line-height:1.65}
.hero-ring{position:relative;width:120px;height:120px;flex:0 0 120px}
.ring{transform:rotate(-90deg)}
.ring-bg{fill:none;stroke:var(--line-soft);stroke-width:7}
.ring-fg{
  fill:none;stroke:var(--accent);stroke-width:7;stroke-linecap:round;
  stroke-dasharray:327;stroke-dashoffset:327;transition:stroke-dashoffset .8s cubic-bezier(.3,1,.4,1);
}
html[data-theme="dark"] .ring-fg{filter:drop-shadow(0 0 7px rgba(255,92,70,.55))}
.ring-center{position:absolute;inset:0;display:grid;place-content:center;text-align:center}
.ring-num{font-size:28px;font-weight:600;line-height:1;font-variant-numeric:tabular-nums;letter-spacing:-.02em}
.ring-lbl{font-size:11px;color:var(--ink-3);margin-top:3px;letter-spacing:.1em;text-transform:uppercase}

/* ============ Stats ============ */
.stat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;margin-bottom:36px}
.stat-grid.wide{margin-bottom:26px}
.stat{
  background:var(--surface);-webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  border:1px solid var(--line-soft);border-radius:var(--radius);padding:16px 18px;
  transition:border-color .18s ease,transform .18s ease;
}
.stat:hover{border-color:var(--line);transform:translateY(-1px)}
.stat-num{
  font-size:26px;font-weight:600;line-height:1.1;letter-spacing:-.02em;
  font-variant-numeric:tabular-nums;
}
.stat-lbl{font-size:12px;color:var(--ink-3);margin-top:5px;letter-spacing:.04em}

.section-title{
  font-size:11px;letter-spacing:.16em;text-transform:uppercase;color:var(--ink-3);
  margin:28px 0 14px;font-weight:600;
}

/* ============ Mode cards ============ */
.mode-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(216px,1fr));gap:13px}
.mode-card{
  background:var(--surface);-webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  border:1px solid var(--line-soft);border-radius:var(--radius-lg);
  padding:20px;text-align:left;
  transition:transform .2s cubic-bezier(.2,.8,.3,1),box-shadow .2s ease,border-color .2s ease;
}
.mode-card:hover{
  transform:translateY(-3px);box-shadow:var(--shadow-lg);border-color:var(--line);
}
.mode-icon{font-size:19px;color:var(--accent);margin-bottom:12px}
html[data-theme="dark"] .mode-icon{text-shadow:0 0 16px rgba(255,92,70,.5)}
.mode-name{font-size:15.5px;font-weight:600;letter-spacing:-.005em}
.mode-desc{font-size:12.5px;color:var(--ink-3);margin-top:5px;line-height:1.55}
.mode-card.primary{
  background:linear-gradient(155deg,var(--accent-2) 0%,#cf3520 100%);border-color:transparent;
  box-shadow:0 14px 34px -14px rgba(255,92,70,.7),inset 0 1px 0 rgba(255,255,255,.22);
}
.mode-card.primary:hover{transform:translateY(-3px);box-shadow:0 20px 44px -14px rgba(255,92,70,.8),inset 0 1px 0 rgba(255,255,255,.28)}
.mode-card.primary .mode-icon,.mode-card.primary .mode-name{color:#fff}
.mode-card.primary .mode-icon{text-shadow:none}
.mode-card.primary .mode-desc{color:rgba(255,255,255,.78)}
.mode-card.primary b{color:#fff}

/* ============ Quiz ============ */
.quiz-bar{
  position:sticky;top:0;z-index:5;display:flex;align-items:center;gap:16px;
  padding:16px 0 14px;margin-bottom:8px;
  background:var(--bg);
}
html[data-theme="dark"] .quiz-bar{
  background:rgba(8,8,10,.72);
  -webkit-backdrop-filter:blur(18px) saturate(180%);backdrop-filter:blur(18px) saturate(180%);
  padding-inline:14px;margin-inline:-14px;border-bottom:1px solid var(--line-soft);
}
.quiz-title{font-weight:600;font-size:16px;letter-spacing:-.01em}
.quiz-progress{
  margin-left:auto;font-size:12.5px;color:var(--ink-3);display:flex;gap:8px;align-items:center;
  font-variant-numeric:tabular-nums;
}
.ghost-btn{
  padding:6px 12px;border-radius:9px;border:1px solid var(--line);font-size:13px;
  color:var(--ink-2);background:var(--surface);transition:all .16s ease
}
.ghost-btn:hover{border-color:var(--ink-3);color:var(--ink)}
.ghost-btn.danger{color:var(--accent);border-color:var(--accent-soft)}
.ghost-btn.danger:hover{background:var(--accent-soft)}
.quiz-wrap{max-width:720px;margin:0 auto}
.card-q{
  background:var(--surface);
  -webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  border:1px solid var(--line);border-radius:var(--radius-lg);
  padding:40px 42px 32px;box-shadow:var(--shadow-lg);
  min-height:420px;display:flex;flex-direction:column;
}
html[data-theme="dark"] .card-q{
  background:linear-gradient(165deg,rgba(255,255,255,.062),rgba(255,255,255,.022));
}
.q-tags{display:flex;gap:7px;margin-bottom:20px;flex-wrap:wrap}
.tag{
  font-size:10.5px;letter-spacing:.09em;padding:3.5px 9px;border-radius:20px;
  background:var(--surface-2);color:var(--ink-3);border:1px solid var(--line-soft);
  text-transform:uppercase;font-weight:500;
}
.tag.lv{
  background:var(--accent-soft);color:var(--accent);border-color:transparent;font-weight:600;
  box-shadow:inset 0 0 0 1px rgba(255,92,70,.16);
}
.q-prompt{
  font-family:var(--jp);font-size:46px;line-height:1.35;font-weight:400;
  letter-spacing:.03em;word-break:keep-all;color:var(--ink);
}
html[data-theme="dark"] .q-prompt{text-shadow:0 4px 34px rgba(255,255,255,.07)}
.q-prompt-ro{
  display:block;font-family:var(--ui);font-size:13.5px;color:var(--muted);
  margin-top:8px;letter-spacing:.14em;text-transform:lowercase;font-weight:400;
}
.q-prompt.small{font-size:26px;line-height:1.7}
.q-prompt.small .q-prompt-ro{font-size:12.5px;margin-top:5px}
.q-prompt.cn{font-family:var(--ui);font-size:30px;font-weight:600;letter-spacing:-.01em}
.q-sub{color:var(--ink-3);font-size:13.5px;margin-top:12px;font-family:var(--jp-sans)}
.speak-btn{
  align-self:flex-start;margin-top:22px;display:inline-flex;align-items:center;gap:8px;
  padding:9px 15px;border-radius:11px;background:var(--surface-2);border:1px solid var(--line-soft);
  font-size:13px;color:var(--ink-2);transition:all .16s ease
}
.speak-btn:hover{border-color:var(--accent);color:var(--accent);background:var(--accent-soft)}
.speak-btn .sp-icon{font-size:11px}
.speak-btn.playing{
  background:var(--accent-soft);border-color:var(--accent);color:var(--accent);
  box-shadow:0 0 0 1px rgba(255,92,70,.2),0 6px 20px -8px rgba(255,92,70,.55);
}

.q-options{display:grid;gap:9px;margin-top:28px}
.opt{
  display:flex;align-items:center;gap:13px;padding:14px 17px;border-radius:12px;
  border:1px solid var(--line-soft);text-align:left;background:var(--surface-2);
  -webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  transition:transform .16s cubic-bezier(.2,.8,.3,1),border-color .16s ease,background .16s ease,box-shadow .16s ease;
}
.opt:hover{
  background:var(--surface-solid);border-color:var(--line);transform:translateY(-1px);
}
.opt-key{
  width:24px;height:24px;flex:0 0 24px;border-radius:7px;background:var(--surface-solid);
  border:1px solid var(--line);display:grid;place-items:center;font-size:11.5px;
  color:var(--ink-3);font-weight:600;font-variant-numeric:tabular-nums;transition:all .16s ease;
}
.opt:hover .opt-key{color:var(--ink);border-color:var(--ink-3)}
.opt-text{font-size:15.5px;display:flex;flex-direction:column;align-items:flex-start;gap:2px}
.opt-ro{font-size:11.5px;color:var(--muted);letter-spacing:.1em;text-transform:lowercase}
.opt.jp{font-family:var(--jp)}
.opt.ok{
  border-color:rgba(62,207,142,.5);
  background:linear-gradient(90deg,var(--green-soft),transparent);
  box-shadow:inset 0 0 0 1px rgba(62,207,142,.18),0 10px 30px -14px rgba(62,207,142,.45);
}
.opt.ok .opt-key{background:var(--green);color:#04140d;border-color:transparent;box-shadow:0 4px 12px -4px rgba(62,207,142,.7)}
.opt.bad{
  border-color:rgba(255,92,70,.5);
  background:linear-gradient(90deg,var(--accent-soft),transparent);
  box-shadow:inset 0 0 0 1px rgba(255,92,70,.18),0 10px 30px -14px rgba(255,92,70,.45);
}
.opt.bad .opt-key{background:var(--accent);color:#fff;border-color:transparent;box-shadow:0 4px 12px -4px rgba(255,92,70,.7)}
.opt.dim{opacity:.32}
.opt:disabled{cursor:default}

.q-feedback{display:none;margin-top:24px;padding-top:20px;border-top:1px solid var(--line-soft)}
.q-feedback.show{display:block;animation:fade .24s ease}
.fb-head{font-size:15px;font-weight:600;margin-bottom:12px;letter-spacing:-.01em}
.fb-head.ok{color:var(--green)}
.fb-head.bad{color:var(--accent)}
.fb-body{font-size:14px;color:var(--ink-2);line-height:1.85}
.fb-body .fb-row{display:flex;gap:9px;align-items:baseline;padding:2px 0}
.fb-body .fb-k{
  color:var(--ink-3);font-size:10.5px;letter-spacing:.1em;min-width:38px;
  text-transform:uppercase;font-weight:500;
}
.fb-body .jp{font-family:var(--jp);font-size:17px;color:var(--ink)}
.fb-ex{border-left:2px solid rgba(255,92,70,.4);padding-left:13px;margin-top:10px}
.fb-ex-jp{font-family:var(--jp);font-size:16px}
.fb-ex-zh{font-size:13px;color:var(--ink-3)}

.q-actions{display:flex;gap:10px;margin-top:auto;padding-top:26px}
.pill{
  padding:11px 22px;border-radius:11px;font-size:14px;font-weight:500;border:1px solid var(--line);
  background:var(--surface-2);color:var(--ink-2);transition:all .16s ease;
}
.pill:hover{background:var(--surface-solid);border-color:var(--ink-3);color:var(--ink)}
.pill.ok{
  background:linear-gradient(155deg,var(--accent-2),#cf3520);color:#fff;border-color:transparent;flex:1;
  box-shadow:0 12px 28px -12px rgba(255,92,70,.75),inset 0 1px 0 rgba(255,255,255,.22);font-weight:600;
}
.pill.ok:hover{color:#fff;filter:brightness(1.06);transform:translateY(-1px)}
.pill.again{border-color:rgba(255,92,70,.3);color:var(--accent)}
.pill.again:hover{background:var(--accent-soft);border-color:var(--accent)}
.q-hint{text-align:center;font-size:11.5px;color:var(--ink-3);margin-top:16px}
kbd{
  font-family:var(--ui);font-size:10.5px;border:1px solid var(--line);border-bottom-width:2px;
  border-radius:5px;padding:1px 5px;color:var(--ink-3);margin:0 1px;background:var(--surface-2)
}

/* ============ Writing ============ */
.write-wrap{max-width:860px;margin:0 auto}
.write-card{
  background:var(--surface);
  -webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  border:1px solid var(--line);border-radius:var(--radius-lg);
  padding:28px 30px 24px;box-shadow:var(--shadow-lg)
}
html[data-theme="dark"] .write-card{background:linear-gradient(165deg,rgba(255,255,255,.055),rgba(255,255,255,.02))}
.w-prompt{display:flex;align-items:center;gap:18px}
.speak-btn.big{padding:13px 20px;font-size:14px;margin-top:0;border-radius:13px}
.speak-btn.big .sp-icon{font-size:14px}
.w-prompt-body{flex:1;min-width:0}
.w-zh{font-size:23px;font-weight:600;letter-spacing:-.015em}
.w-ro{
  font-size:15px;color:var(--accent);letter-spacing:.1em;margin-top:4px;
  text-transform:lowercase;font-family:var(--jp-sans);font-weight:500
}
html[data-theme="dark"] .w-ro{text-shadow:0 0 20px rgba(255,92,70,.35)}
.icon-btn{
  width:36px;height:36px;border-radius:10px;border:1px solid var(--line-soft);background:var(--surface-2);
  color:var(--ink-2);display:grid;place-items:center;font-size:14px;transition:all .16s ease;flex:0 0 36px
}
.icon-btn:hover{border-color:var(--accent);color:var(--accent);background:var(--accent-soft)}
.icon-btn.danger{color:var(--accent)}
.icon-btn.small{width:26px;height:26px;flex:0 0 26px;font-size:11px;border-radius:8px}
.w-hint{
  margin-top:12px;font-size:13px;color:var(--ink-3);padding:9px 13px;background:var(--surface-2);
  border-radius:10px;display:none;border:1px dashed var(--line)
}
.w-hint.show{display:block}
.w-canvas-area{margin-top:16px;position:relative}
#pad{
  width:100%;height:auto;touch-action:none;display:block;border-radius:14px;
  background:var(--surface-2);border:1px solid var(--line);cursor:crosshair
}
html[data-theme="dark"] #pad{background:rgba(255,255,255,.028)}
.pad-tools{position:absolute;right:10px;top:10px;display:flex;gap:6px;align-items:center;flex-direction:column}
.pad-divider{width:16px;height:1px;background:var(--line)}
.chip-btn{
  padding:5px 10px;border-radius:8px;border:1px solid var(--line-soft);
  background:var(--surface-solid);color:var(--ink-2);font-size:11.5px;transition:all .16s ease;
  -webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);
}
.chip-btn:hover{border-color:var(--accent);color:var(--accent)}
.chip-btn.active{
  background:linear-gradient(155deg,var(--accent-2),#cf3520);color:#fff;border-color:transparent;
  box-shadow:0 6px 16px -8px rgba(255,92,70,.7);
}
.w-actions{margin-top:16px}
.w-actions .pill{
  width:100%;background:linear-gradient(155deg,var(--accent-2),#cf3520);color:#fff;
  border-color:transparent;padding:12px;font-weight:600;
  box-shadow:0 12px 28px -12px rgba(255,92,70,.7),inset 0 1px 0 rgba(255,255,255,.22);
}
.w-actions .pill:hover{color:#fff;filter:brightness(1.06)}
.w-answer{display:none;margin-top:22px;padding-top:20px;border-top:1px solid var(--line-soft)}
.w-answer.show{display:block;animation:fade .3s ease}
.wa-label{
  font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:var(--ink-3);
  margin-bottom:12px;font-weight:600;
}
.wa-main{margin-bottom:14px}
.wa-kana{display:flex;align-items:center;gap:11px}
.wa-kana span{font-family:var(--jp);font-size:38px;line-height:1.3;word-break:keep-all}
.wa-ro{color:var(--accent);letter-spacing:.1em;font-size:14.5px;margin-top:2px}
.wa-zh{color:var(--ink-2);font-size:13.5px;margin-top:2px}
.reveal-canvas{
  width:100%;height:auto;display:block;border-radius:14px;background:var(--surface-2);
  border:1px solid var(--line);margin-top:6px
}
html[data-theme="dark"] .reveal-canvas{background:rgba(255,255,255,.028)}
.wa-grade{margin-top:18px}
.wa-grade-title{font-size:11px;color:var(--ink-3);letter-spacing:.12em;text-transform:uppercase;margin-bottom:9px}
.wa-grade-btns{display:grid;grid-template-columns:repeat(3,1fr);gap:9px}
.grade{
  padding:12px 0;border-radius:11px;border:1px solid var(--line-soft);font-size:13.5px;
  background:var(--surface-2);transition:all .16s cubic-bezier(.2,.8,.3,1);font-weight:500;
}
.grade:hover{transform:translateY(-2px);box-shadow:var(--shadow)}
.grade.again{color:var(--accent);border-color:rgba(255,92,70,.3)}
.grade.again:hover{background:var(--accent-soft);border-color:var(--accent);box-shadow:0 8px 22px -10px rgba(255,92,70,.6)}
.grade.hard{color:var(--amber);border-color:rgba(242,177,60,.3)}
.grade.hard:hover{border-color:var(--amber);box-shadow:0 8px 22px -10px rgba(242,177,60,.55)}
.grade.ok{color:var(--green);border-color:rgba(62,207,142,.3)}
.grade.ok:hover{border-color:var(--green);box-shadow:0 8px 22px -10px rgba(62,207,142,.55)}

/* ============ Library ============ */
.lib-head{
  position:sticky;top:0;z-index:5;background:var(--bg);padding:16px 0 12px;margin-bottom:8px;
}
html[data-theme="dark"] .lib-head{
  background:rgba(8,8,10,.72);
  -webkit-backdrop-filter:blur(18px) saturate(180%);backdrop-filter:blur(18px) saturate(180%);
  padding-inline:14px;margin-inline:-14px;border-bottom:1px solid var(--line-soft);
}
.search-box{
  display:flex;align-items:center;gap:10px;background:var(--surface);border:1px solid var(--line-soft);
  border-radius:12px;padding:11px 15px;box-shadow:var(--shadow);transition:border-color .18s ease,box-shadow .18s ease
}
.search-box:focus-within{
  border-color:var(--accent);
  box-shadow:0 0 0 3px var(--accent-soft),var(--shadow);
}
.sb-icon{color:var(--ink-3);font-size:16px}
#libSearch{flex:1;border:none;outline:none;background:transparent;font-size:15px;color:var(--ink)}
#libSearch::placeholder{color:var(--ink-3)}
.lib-filters{display:flex;gap:7px;margin-top:11px;flex-wrap:wrap}
.lib-tools{display:flex;gap:8px;margin-top:11px;flex-wrap:wrap}
.lib-list{display:grid;gap:7px}
.lib-row{
  display:flex;align-items:center;gap:14px;background:var(--surface);
  -webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  border:1px solid var(--line-soft);border-radius:12px;padding:12px 16px;
  transition:border-color .16s ease,transform .16s ease;
}
.lib-row:hover{border-color:var(--line);transform:translateY(-1px)}
.lib-kana{font-family:var(--jp);font-size:22px;min-width:130px;line-height:1.35;display:flex;flex-direction:column;gap:3px}
.lib-kana-ro{font-family:var(--ui);font-size:11.5px;color:var(--muted);letter-spacing:.1em;line-height:1.25;text-transform:lowercase}
.lib-ro{display:none}
.lib-zh{font-size:13.5px;color:var(--ink-2);flex:1}
.lib-state{
  font-size:10.5px;color:var(--ink-3);padding:3px 9px;border-radius:20px;background:var(--surface-2);
  border:1px solid var(--line-soft);white-space:nowrap;letter-spacing:.06em;text-transform:uppercase;font-weight:500;
}
.lib-state.new{color:var(--ink-3)}
.lib-state.learn{color:var(--blue)}
.lib-state.due{color:var(--accent);background:var(--accent-soft);border-color:transparent}
.lib-state.master{color:var(--green)}
.lib-actions{display:flex;gap:6px}
.lib-empty{text-align:center;color:var(--ink-3);padding:60px 0;font-size:14px}
.num-input{
  width:78px;padding:7px 10px;border-radius:9px;border:1px solid var(--line);
  background:var(--surface-solid);text-align:center;font-variant-numeric:tabular-nums;
}
.num-input:focus{outline:none;border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-soft)}
.select{
  max-width:230px;padding:7px 10px;border-radius:9px;border:1px solid var(--line);
  background:var(--surface-solid);font-size:13px;
}
.select:focus{outline:none;border-color:var(--accent)}

/* ============ Lesson ============ */
.lesson-progress{font-size:12.5px;color:var(--ink-3);margin-top:8px}
.lesson-wrap{display:grid;grid-template-columns:280px 1fr;gap:20px;align-items:start}
.lesson-list{display:flex;flex-direction:column;gap:6px;position:sticky;top:96px}
.lesson-item{
  display:flex;align-items:center;gap:10px;padding:11px 13px;border-radius:11px;
  background:var(--surface);-webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  border:1px solid var(--line-soft);cursor:pointer;
  transition:border-color .16s ease,background .16s ease,transform .16s ease;text-align:left;width:100%
}
.lesson-item:hover{border-color:var(--line);transform:translateX(2px)}
.lesson-item.active{
  border-color:var(--accent);background:var(--accent-soft);
  box-shadow:inset 0 0 0 1px rgba(255,92,70,.16);
}
.lesson-item .li-idx{
  font-size:11px;color:var(--ink-3);min-width:22px;height:22px;border-radius:50%;
  background:var(--surface-2);display:flex;align-items:center;justify-content:center;flex:0 0 auto;
  font-variant-numeric:tabular-nums;
}
.lesson-item.done .li-idx{background:var(--green-soft);color:var(--green)}
.lesson-item .li-body{flex:1;min-width:0}
.lesson-item .li-title{font-size:13.5px;color:var(--ink);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.lesson-item .li-sub{font-size:11px;color:var(--ink-3);margin-top:2px}
.lesson-detail{
  background:var(--surface);-webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  border:1px solid var(--line);border-radius:var(--radius-lg);
  padding:26px 28px 24px;min-height:420px;box-shadow:var(--shadow-lg)
}
html[data-theme="dark"] .lesson-detail{background:linear-gradient(165deg,rgba(255,255,255,.055),rgba(255,255,255,.02))}
.lesson-detail .ld-head{margin-bottom:18px}
.lesson-detail .ld-title{font-family:var(--display);font-size:28px;font-weight:400;letter-spacing:.01em}
.lesson-detail .ld-goal{font-size:13px;color:var(--ink-3);margin-top:6px;line-height:1.7}
.lesson-detail .ld-actions{display:flex;gap:9px;margin:18px 0 6px;flex-wrap:wrap}
.ld-sec{margin-top:22px}
.ld-sec-title{
  font-size:11px;color:var(--ink-3);letter-spacing:.14em;margin-bottom:10px;
  text-transform:uppercase;font-weight:600;
}
.ld-word{display:flex;align-items:baseline;gap:12px;padding:9px 0;border-bottom:1px solid var(--line-soft)}
.ld-word:last-child{border-bottom:none}
.ld-w-k{font-family:var(--jp);font-size:20px;min-width:112px}
.ld-w-h{font-family:var(--jp);font-size:13.5px;color:var(--ink-3);min-width:104px}
.ld-w-r{font-size:12.5px;color:var(--accent);min-width:104px;letter-spacing:.06em}
.ld-w-z{font-size:13px;color:var(--ink-2);flex:1}
.ld-memo{font-size:12.5px;color:var(--ink-3);line-height:1.8;background:var(--surface-2);
  border-radius:10px;padding:12px 14px;border:1px solid var(--line-soft)}
.ld-memo b{color:var(--ink-2);font-weight:600}
.ld-kana-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(92px,1fr));gap:9px}
.ld-kana{
  background:var(--surface-2);border:1px solid var(--line-soft);border-radius:11px;
  padding:12px 8px;text-align:center;cursor:pointer;transition:all .16s cubic-bezier(.2,.8,.3,1)
}
.ld-kana:hover{
  border-color:var(--accent);transform:translateY(-2px);
  box-shadow:0 8px 22px -10px rgba(255,92,70,.55);
}
.ld-kana .kk{font-family:var(--jp);font-size:26px;line-height:1.2}
.ld-kana .kr{font-size:11.5px;color:var(--accent);margin-top:4px;letter-spacing:.06em}
.ld-kana .kt{font-size:11px;color:var(--ink-3);margin-top:2px}
.ld-ex{margin-top:11px;border-left:2px solid rgba(255,92,70,.4);padding-left:13px}
.ld-ex-jp{font-family:var(--jp);font-size:15.5px;line-height:1.75}
.ld-ex-zh{font-size:12.5px;color:var(--ink-3);margin-top:3px}

/* ============ Stats ============ */
.chart{
  display:flex;align-items:flex-end;gap:6px;height:150px;background:var(--surface);
  -webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  border:1px solid var(--line-soft);border-radius:var(--radius);padding:18px 16px 12px
}
.chart-col{flex:1;display:flex;flex-direction:column;align-items:center;gap:7px;height:100%;justify-content:flex-end}
.chart-bar{
  width:100%;max-width:30px;border-radius:6px 6px 3px 3px;min-height:3px;transition:height .5s cubic-bezier(.2,.8,.3,1);
  position:relative;background:linear-gradient(180deg,var(--accent-2),#cf3520);
}
html[data-theme="dark"] .chart-bar{box-shadow:0 4px 18px -6px rgba(255,92,70,.6)}
.chart-bar.zero{background:var(--line);box-shadow:none}
.chart-lbl{font-size:9.5px;color:var(--ink-3);white-space:nowrap}
.dist{display:flex;flex-direction:column;gap:10px}
.dist-row{display:flex;align-items:center;gap:12px}
.dist-name{font-size:12.5px;color:var(--ink-2);width:100px;flex:0 0 100px}
.dist-bar{
  flex:1;height:26px;background:var(--surface-2);border-radius:7px;overflow:hidden;
  border:1px solid var(--line-soft)
}
.dist-fill{
  height:100%;border-radius:6px;transition:width .6s cubic-bezier(.2,.8,.3,1);
  background:linear-gradient(90deg,var(--accent),var(--accent-2));
}
html[data-theme="dark"] .dist-fill{box-shadow:0 0 20px -4px rgba(255,92,70,.6)}
.dist-num{font-size:12px;color:var(--ink-3);width:52px;text-align:right;font-variant-numeric:tabular-nums}

.mini-log{display:flex;flex-direction:column;gap:5px}
.log-row{
  display:flex;align-items:center;gap:11px;padding:9px 14px;background:var(--surface);
  -webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  border:1px solid var(--line-soft);border-radius:10px;font-size:13.5px
}
.log-row .lk{font-family:var(--jp);font-size:17px;min-width:110px}
.log-row .lz{color:var(--ink-2);flex:1;font-size:13px}
.log-row .ls{font-size:10.5px;padding:2.5px 9px;border-radius:20px;letter-spacing:.06em;text-transform:uppercase;font-weight:600}
.log-row .ls.bad{background:var(--accent-soft);color:var(--accent)}
.log-row .ls.ok{background:var(--green-soft);color:var(--green)}
.empty{color:var(--ink-3);font-size:13px;padding:22px 0;text-align:center}

/* ============ Settings ============ */
.set-card{
  background:var(--surface);-webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  border:1px solid var(--line-soft);border-radius:var(--radius-lg);
  padding:6px 22px;margin-bottom:16px;box-shadow:var(--shadow)
}
.set-row{display:flex;align-items:center;gap:20px;padding:16px 0;border-bottom:1px solid var(--line-soft)}
.set-row:last-child{border-bottom:none}
.set-info{flex:1}
.set-name{font-size:14.5px;font-weight:500}
.set-desc{font-size:12.5px;color:var(--ink-3);margin-top:2px}
.set-title{
  font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:var(--ink-3);
  padding:18px 0 8px;font-weight:600;
}
.set-note{font-size:13px;color:var(--ink-2);line-height:1.8;padding:6px 0}
code{
  background:var(--surface-2);border:1px solid var(--line-soft);border-radius:5px;
  padding:1px 5px;font-size:12.5px
}
.code{
  background:var(--surface-2);border:1px solid var(--line-soft);border-radius:10px;padding:14px;font-size:12.5px;
  overflow-x:auto;line-height:1.7;margin:8px 0;color:var(--ink-2)
}
.range{width:170px;accent-color:var(--accent)}
.range-val{font-size:12.5px;color:var(--ink-3);width:32px;font-variant-numeric:tabular-nums}
.switch{position:relative;width:44px;height:25px;flex:0 0 44px}
.switch input{opacity:0;width:0;height:0}
.switch span{
  position:absolute;inset:0;background:var(--line);border-radius:25px;
  transition:background .22s cubic-bezier(.2,.8,.3,1)
}
.switch span::after{
  content:"";position:absolute;left:3px;top:3px;width:19px;height:19px;border-radius:50%;
  background:#fff;transition:transform .22s cubic-bezier(.2,.8,.3,1);box-shadow:0 1px 3px rgba(0,0,0,.35)
}
.switch input:checked + span{
  background:linear-gradient(150deg,var(--accent-2),#cf3520);
  box-shadow:0 4px 14px -5px rgba(255,92,70,.75);
}
.switch input:checked + span::after{transform:translateX(19px)}

/* ============ Toast ============ */
.toast{
  position:fixed;left:50%;bottom:34px;transform:translate(-50%,20px);opacity:0;pointer-events:none;
  background:var(--surface-solid);color:var(--ink);padding:12px 22px;border-radius:12px;font-size:13.5px;
  transition:all .3s cubic-bezier(.2,.8,.3,1);z-index:100;box-shadow:var(--shadow-lg);
  -webkit-backdrop-filter:var(--blur);backdrop-filter:var(--blur);
  border:1px solid var(--line);
}
.toast.show{opacity:1;transform:translate(-50%,0)}

/* ============ Motion preference ============ */
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.01ms!important;transition-duration:.01ms!important}
}

/* ============ Responsive ============ */
@media (max-width:900px){
  .app{flex-direction:column}
  .sidebar{
    width:100%;flex:0 0 auto;flex-direction:row;align-items:center;gap:12px;
    padding:10px 14px;border-right:none;border-bottom:1px solid var(--line);overflow-x:auto;
    background:var(--surface-solid);
  }
  html[data-theme="dark"] .sidebar{
    background:rgba(10,10,13,.9);
    -webkit-backdrop-filter:blur(20px) saturate(180%);backdrop-filter:blur(20px) saturate(180%);
  }
  .brand{padding:0;gap:9px}
  .brand-text{display:none}
  .nav{flex-direction:row;gap:4px;flex:1;overflow-x:auto;-webkit-overflow-scrolling:touch}
  .nav-item{padding:7px 11px;font-size:13px;white-space:nowrap;background:none}
  .nav-item.active::before{display:none}
  .nav-item span.ni{display:none}
  .sidebar-foot{flex-direction:row;margin:0;padding:0;gap:9px;align-items:center}
  .streak{padding:0}
  .streak-num{font-size:19px}
  .streak-lbl{display:none}
  .level-switch{display:flex;gap:4px}
  .lv{padding:6px 9px}
  .view{padding:22px 18px 90px}
  .hero{flex-direction:column;align-items:flex-start;gap:18px}
  .hero-title{font-size:30px}
  .stat-grid{grid-template-columns:repeat(2,1fr)}
  .card-q{padding:26px 20px 22px;min-height:auto}
  .q-prompt{font-size:34px}
  .lib-row{flex-wrap:wrap;gap:8px}
  .lib-kana{min-width:auto}
  .lib-zh{flex:1 1 100%}
  .lesson-wrap{grid-template-columns:1fr}
  .lesson-list{position:static;flex-direction:row;overflow-x:auto;padding-bottom:4px}
  .lesson-item{flex:0 0 auto}
  .lesson-item .li-title{white-space:nowrap}
  .wa-grade-btns{grid-template-columns:1fr}
  .q-actions{flex-direction:column}
}