:root{
  --bg:#fff; --text:#1d1d1f; --text2:#6e6e73; --text3:#aeaeb2;
  --line:rgba(0,0,0,.08); --fill:#f5f5f7;
  --green:#34c759; --green-t:rgba(52,199,89,.12);
  --red:#ff3b30;   --red-t:rgba(255,59,48,.10);
  --learn:#c7c7cc;
  --r:18px;
  --jp:"Hiragino Sans","Hiragino Kaku Gothic ProN","Noto Sans JP","Yu Gothic",system-ui,sans-serif;
  --safe-b:env(safe-area-inset-bottom,0px);
  color-scheme:light;
}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{margin:0;background:var(--bg);color:var(--text)}
body{font:100%/1.45 -apple-system,BlinkMacSystemFont,"SF Pro Text",system-ui,sans-serif;-webkit-font-smoothing:antialiased;overscroll-behavior-y:none}
button{font:inherit;color:inherit;border:0;background:none;cursor:pointer;touch-action:manipulation}
[hidden]{display:none!important}
#app{max-width:480px;margin:0 auto;padding:0 16px calc(84px + var(--safe-b))}

/* ---------- titles ---------- */
.large-title{padding:28px 4px 12px}
.large-title h1{font-size:2.125rem;line-height:1.1;letter-spacing:-.022em;font-weight:700;margin:0}
.sub{margin:4px 0 0;color:var(--text2);font-size:.875rem}
.sub.warn{color:var(--red)}

/* ---------- today card ---------- */
.today{display:flex;align-items:center;justify-content:space-between;gap:16px;
  padding:18px 18px 18px 22px;border:1px solid var(--line);border-radius:var(--r);margin-top:8px}
.today-nums{display:flex;gap:28px}
.today-nums div{display:flex;flex-direction:column}
.num{font-size:2rem;font-weight:600;letter-spacing:-.02em;line-height:1.1;font-variant-numeric:tabular-nums}
.lbl{font-size:.8125rem;color:var(--text2)}
.btn-primary{background:var(--text);color:#fff;font-weight:600;padding:13px 26px;border-radius:999px;
  transition:transform .1s ease-out,opacity .2s}
.btn-primary:active{transform:scale(.96)}
.btn-primary:disabled{opacity:.25;pointer-events:none}

/* ---------- overall progress ---------- */
.overall{padding:18px 4px 6px}
.bar{height:6px;border-radius:3px;background:var(--fill);overflow:hidden;display:flex}
.bar i{display:block;height:100%;transition:width .5s cubic-bezier(.2,.8,.2,1)}
.bar .k{background:var(--green)} .bar .l{background:var(--learn)}
.legend{display:flex;gap:16px;margin-top:10px;font-size:.8125rem;color:var(--text2);font-variant-numeric:tabular-nums}
.legend span{display:inline-flex;align-items:center;gap:6px}
.dot{width:8px;height:8px;border-radius:50%;display:inline-block}
.dot.known{background:var(--green)} .dot.learning{background:var(--learn)} .dot.new{background:transparent;box-shadow:inset 0 0 0 1.5px var(--learn)}

/* ---------- list tools ---------- */
.list-tools{position:sticky;top:0;z-index:5;padding:14px 0 10px;margin:0 -16px;padding-left:16px;padding-right:16px;
  background:rgba(255,255,255,.82);-webkit-backdrop-filter:blur(20px) saturate(180%);backdrop-filter:blur(20px) saturate(180%)}
input[type=search]{width:100%;font:inherit;font-size:1rem;padding:10px 14px;border-radius:12px;border:0;background:var(--fill);outline:none;color:var(--text);-webkit-appearance:none}
input[type=search]::placeholder{color:var(--text3)}
.seg{display:flex;margin-top:10px;background:var(--fill);border-radius:10px;padding:2px}
.seg button{flex:1;padding:6px 0;font-size:.8125rem;font-weight:500;border-radius:8px;color:var(--text2);transition:background .2s,color .2s}
.seg button.on{background:#fff;color:var(--text);box-shadow:0 1px 3px rgba(0,0,0,.1)}

/* ---------- list ---------- */
.vlist{list-style:none;margin:0;padding:0}
.vlist li{display:flex;align-items:center;gap:14px;padding:12px 4px;border-bottom:1px solid var(--line);cursor:pointer;transition:background .15s}
.vlist li:active{background:var(--fill)}
.vlist .w{flex:0 0 auto;min-width:88px;max-width:45%}
.vlist .w b{display:block;font:500 1.125rem/1.3 var(--jp)}
.vlist .w small{display:block;font:.75rem/1.3 var(--jp);color:var(--text2)}
.vlist .m{flex:1;font-size:.9375rem;color:var(--text2);overflow:hidden;text-overflow:ellipsis;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical}
.vlist .dot{flex:0 0 auto}
.empty{text-align:center;color:var(--text3);padding:40px 0}
.more{display:block;width:100%;padding:16px;color:var(--text2);font-size:.875rem}

/* ---------- tab bar ---------- */
.tabbar{position:fixed;left:0;right:0;bottom:0;z-index:20;display:flex;justify-content:center;gap:0;
  padding:6px 0 calc(6px + var(--safe-b));
  background:rgba(255,255,255,.82);-webkit-backdrop-filter:blur(20px) saturate(180%);backdrop-filter:blur(20px) saturate(180%);
  border-top:1px solid var(--line)}
.tabbar button{flex:0 1 160px;display:flex;flex-direction:column;align-items:center;gap:1px;font-size:.6875rem;font-weight:500;color:var(--text3);padding:4px 0;transition:color .2s}
.tabbar .ti{font:500 1.25rem/1.2 var(--jp)}
.tabbar button.on{color:var(--text)}

/* ---------- study ---------- */
.study{position:fixed;inset:0;z-index:40;background:#fff;display:flex;flex-direction:column;
  max-width:480px;margin:0 auto;padding:12px 16px calc(16px + var(--safe-b));animation:rise .35s cubic-bezier(.2,.9,.25,1)}
@keyframes rise{from{transform:translateY(24px);opacity:0}to{transform:none;opacity:1}}
.study-top{display:flex;align-items:center;gap:14px;height:44px}
.icon-btn{width:36px;height:36px;border-radius:50%;background:var(--fill);color:var(--text2);font-size:.875rem;display:grid;place-items:center}
.icon-btn:active{transform:scale(.92)}
.progress{flex:1;height:4px;border-radius:2px;background:var(--fill);overflow:hidden}
.progress i{display:block;height:100%;width:0;background:var(--text);transition:width .35s cubic-bezier(.2,.8,.2,1)}
.count{font-size:.8125rem;color:var(--text2);font-variant-numeric:tabular-nums;min-width:44px;text-align:right}

.stage{flex:1;display:flex;align-items:center;justify-content:center;perspective:1400px;padding:18px 0;min-height:0}
.card{position:relative;width:100%;height:100%;max-height:520px;touch-action:none;user-select:none;-webkit-user-select:none;will-change:transform}
.face{position:absolute;inset:0;border-radius:24px;background:#fff;border:1px solid var(--line);
  box-shadow:0 10px 30px rgba(0,0,0,.06),0 1px 2px rgba(0,0,0,.04);
  display:flex;flex-direction:column;align-items:center;justify-content:center;padding:28px 24px;text-align:center;
  backface-visibility:hidden;-webkit-backface-visibility:hidden;transition:transform .5s cubic-bezier(.2,.8,.2,1),border-color .15s}
.back{transform:rotateY(180deg)}
.card.flipped .front{transform:rotateY(-180deg)}
.card.flipped .back{transform:rotateY(0)}
.tag{position:absolute;top:18px;left:20px;font-size:.6875rem;letter-spacing:.06em;text-transform:uppercase;color:var(--text3);font-weight:600}
.jp-big{font:500 clamp(3rem,16vw,4.5rem)/1.15 var(--jp);letter-spacing:.02em;word-break:keep-all}
.jp-big.long{font-size:clamp(2rem,10vw,2.75rem)}
.jp-mid{font:500 2.25rem/1.2 var(--jp)}
.jp-small{font:1.125rem/1.4 var(--jp);color:var(--text2);margin-top:8px;min-height:1.4em}
.hint{position:absolute;bottom:18px;margin:0;font-size:.8125rem;color:var(--text3)}
.meaning{font-size:1.375rem;font-weight:600;letter-spacing:-.01em;line-height:1.3;margin-top:20px}
.example{margin-top:24px;padding-top:18px;border-top:1px solid var(--line);width:100%}
.example:empty,.example.none{display:none}
.ex-jp{font:1.0625rem/1.6 var(--jp);margin:0}
.ex-en{font-size:.875rem;color:var(--text2);margin:6px 0 0}

.stamp{position:absolute;top:22px;padding:4px 12px;border-radius:8px;font-weight:700;font-size:.9375rem;opacity:0;pointer-events:none;border:2px solid}
.stamp.missed{right:22px;color:var(--red);border-color:var(--red)}
.stamp.got{left:22px;color:var(--green);border-color:var(--green)}

.grade{display:flex;gap:12px;transition:opacity .25s}
.grade.off{opacity:0;pointer-events:none}
.grade button{flex:1;padding:16px 0;border-radius:16px;font-weight:600;font-size:1.0625rem;transition:transform .1s ease-out,background .15s}
.grade button:active{transform:scale(.97)}
.btn-miss{background:var(--red-t);color:var(--red)}
.btn-got{background:var(--green-t);color:#248a3d}

.done{position:absolute;inset:0;background:#fff;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding:24px;animation:fade .3s ease}
@keyframes fade{from{opacity:0}to{opacity:1}}
.done h2{font-size:1.75rem;letter-spacing:-.02em;margin:24px 0 6px}
.done p{color:var(--text2);margin:0 0 28px}
.done-ring{width:88px;height:88px;border-radius:50%;display:grid;place-items:center;font-size:1.5rem;font-weight:600;font-variant-numeric:tabular-nums}

/* ---------- sheet ---------- */
.scrim{position:fixed;inset:0;z-index:50;background:rgba(0,0,0,.25);animation:fade .25s ease}
.sheet{position:fixed;left:0;right:0;bottom:0;z-index:51;max-width:480px;margin:0 auto;background:#fff;border-radius:22px 22px 0 0;
  padding:10px 24px calc(28px + var(--safe-b));text-align:center;box-shadow:0 -8px 40px rgba(0,0,0,.12);touch-action:none;will-change:transform}
.grabber{width:36px;height:5px;border-radius:3px;background:var(--learn);margin:0 auto 22px}
.stats{display:grid;grid-template-columns:repeat(3,1fr);margin:24px 0 0;padding-top:16px;border-top:1px solid var(--line)}
.stats div{display:flex;flex-direction:column}
.stats dt{font-size:.75rem;color:var(--text2);order:2}
.stats dd{margin:0;font-weight:600;font-size:1.0625rem;font-variant-numeric:tabular-nums}
.stats .g{color:var(--green)} .stats .r{color:var(--red)}

.toast{position:fixed;left:50%;bottom:calc(96px + var(--safe-b));transform:translateX(-50%);z-index:60;background:rgba(29,29,31,.92);color:#fff;
  padding:10px 16px;border-radius:12px;font-size:.875rem;animation:fade .2s ease;max-width:90vw}

@media (prefers-reduced-motion:reduce){
  .face{transition:opacity .2s ease}
  .back{transform:none;opacity:0}
  .card.flipped .front{transform:none;opacity:0}
  .card.flipped .back{opacity:1}
  .study,.scrim,.done{animation:none}
}
@media (prefers-reduced-transparency:reduce){
  .tabbar,.list-tools{background:#fff;backdrop-filter:none;-webkit-backdrop-filter:none}
}

/* ================= GRAMMAR ================= */
.g-title{display:flex;align-items:flex-end;justify-content:space-between;gap:12px}
.seg-sm{margin:0 0 4px;flex:0 0 auto}
.seg-sm button{padding:5px 12px;flex:0 0 auto}
.g-overall{padding-top:8px}
.glist{list-style:none;margin:0;padding:0}
.g-head{font-size:.75rem;font-weight:600;letter-spacing:.06em;text-transform:uppercase;color:var(--text3);padding:22px 4px 6px}
.g-row{display:flex;align-items:center;gap:12px;padding:12px 4px;border-bottom:1px solid var(--line);cursor:pointer;transition:background .15s}
.g-row:active{background:var(--fill)}
.g-txt{flex:1;min-width:0}
.g-txt b{display:block;font:500 1.0625rem/1.35 var(--jp)}
.g-txt span{display:block;font-size:.875rem;color:var(--text2);margin-top:1px}
.g-check{flex:0 0 auto;width:26px;height:26px;border-radius:50%;box-shadow:inset 0 0 0 1.5px var(--learn);position:relative;transition:background .2s,box-shadow .2s,transform .1s}
.g-check:active{transform:scale(.88)}
.g-check.on{background:var(--green);box-shadow:none}
.g-check.on::after{content:"";position:absolute;left:9px;top:5px;width:6px;height:11px;border:solid #fff;border-width:0 2px 2px 0;transform:rotate(45deg)}

.gsheet{position:fixed;left:0;right:0;bottom:0;z-index:51;max-width:480px;margin:0 auto;height:88vh;height:88dvh;background:#fff;
  border-radius:22px 22px 0 0;box-shadow:0 -8px 40px rgba(0,0,0,.12);display:flex;flex-direction:column;will-change:transform}
.gs-handle{padding:10px 24px 14px;text-align:center;touch-action:none;position:relative;border-bottom:1px solid var(--line)}
.gs-handle .grabber{margin-bottom:16px}
.gs-close{position:absolute;top:14px;right:16px;width:30px;height:30px;font-size:.75rem}
.gs-title{font:600 1.75rem/1.25 var(--jp);margin:0;letter-spacing:.01em}
.gs-meaning{margin:6px 0 0;color:var(--text2);font-size:1rem}
.gs-body{flex:1;overflow-y:auto;-webkit-overflow-scrolling:touch;overscroll-behavior:contain;padding:8px 24px 24px}
.gs-lbl{font-size:.75rem;font-weight:600;letter-spacing:.06em;text-transform:uppercase;color:var(--text3);margin:22px 0 8px}
.gs-form{margin:0;white-space:pre-wrap;font:500 1rem/1.7 var(--jp);background:var(--fill);border-radius:14px;padding:14px 16px}
.gs-note{margin:14px 0 0;font-size:.9375rem;line-height:1.6}
.gs-ex{list-style:none;margin:0;padding:0;counter-reset:ex}
.gs-ex li{padding:14px 0 14px 28px;border-bottom:1px solid var(--line);position:relative;counter-increment:ex}
.gs-ex li:last-child{border-bottom:0}
.gs-ex li::before{content:counter(ex);position:absolute;left:0;top:16px;font-size:.75rem;font-weight:600;color:var(--text3);font-variant-numeric:tabular-nums}
.gx-jp{margin:0;font:1.125rem/1.55 var(--jp)}
.gx-kana{margin:2px 0 0;font:.8125rem/1.5 var(--jp);color:var(--text2)}
.gx-tr{margin:6px 0 0;font-size:.9375rem;color:var(--text2)}
.gs-foot{padding:12px 24px calc(12px + var(--safe-b));border-top:1px solid var(--line)}
.gs-learn{width:100%;padding:15px 0;border-radius:16px;font-weight:600;font-size:1.0625rem;background:var(--text);color:#fff;transition:background .2s,color .2s,transform .1s}
.gs-learn:active{transform:scale(.98)}
.gs-learn.on{background:var(--green-t);color:#248a3d}
.gs-lang{position:absolute;top:14px;left:16px;margin:0}
.gs-lang button{padding:4px 10px;font-size:.75rem}