:root{--bg: #111317;--panel: #1a1d23;--panel-2: #232730;--fg: #e9ecf1;--muted: #9aa3b2;--accent: #6ea8fe;--good: #5fd08a;--bad: #f0726f;--warn: #f4c267;--border: #2c313b;font-family:system-ui,-apple-system,Hiragino Kaku Gothic ProN,Yu Gothic,Noto Sans CJK SC,Microsoft YaHei,sans-serif;color-scheme:dark}*{box-sizing:border-box}html,body{margin:0;height:100%;background:var(--bg);color:var(--fg)}#app{height:100%}button{font:inherit;color:inherit;cursor:pointer}kbd{display:inline-block;min-width:1.4em;padding:1px 6px;text-align:center;border:1px solid var(--border);border-bottom-width:2px;border-radius:5px;background:var(--panel-2);font-size:.8em;font-family:ui-monospace,SFMono-Regular,Menlo,monospace;color:var(--muted)}.app-shell{height:100%;display:flex;flex-direction:column;max-width:860px;margin:0 auto;padding:16px}.muted{color:var(--muted)}.center{text-align:center}.topbar{display:flex;align-items:center;justify-content:space-between;gap:12px;padding-bottom:12px;border-bottom:1px solid var(--border)}.topbar h1{font-size:18px;margin:0;font-weight:600}.progress{font-variant-numeric:tabular-nums;color:var(--muted);font-size:14px}.lesson-grid{display:grid;grid-template-columns:repeat(8,1fr);gap:8px;margin:16px 0}.lesson-cell{position:relative;padding:10px 4px 8px;border:1px solid var(--border);border-radius:8px;background:var(--panel);text-align:center;-webkit-user-select:none;user-select:none}.lesson-cell.sel{border-color:var(--accent);background:#1d2735}.lesson-cell.cursor{outline:2px solid var(--accent);outline-offset:1px}.lesson-cell .ln{font-size:15px;font-weight:600}.lesson-cell .due{font-size:11px;color:var(--warn);min-height:14px}.lesson-cell .tot{font-size:11px;color:var(--muted)}.row{display:flex;gap:10px;align-items:center;flex-wrap:wrap}.spacer{flex:1}.btn{padding:8px 14px;border:1px solid var(--border);border-radius:8px;background:var(--panel-2)}.btn.primary{background:var(--accent);color:#0b1220;border-color:var(--accent);font-weight:600}.pill{padding:4px 10px;border-radius:999px;border:1px solid var(--border);background:var(--panel);font-size:13px}.pill.on{border-color:var(--accent);color:var(--accent)}.help{margin-top:auto;padding-top:12px;border-top:1px solid var(--border);color:var(--muted);font-size:13px;line-height:1.9}.card-area{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:20px;text-align:center}.qtype-tag{color:var(--muted);font-size:13px;letter-spacing:.04em}.prompt-jp{font-size:52px;font-weight:600;line-height:1.2}.prompt-cn{font-size:34px;font-weight:600}.prompt-sub{font-size:18px;color:var(--muted)}.answer-input{font:inherit;font-size:30px;text-align:center;width:min(440px,80vw);padding:10px 14px;background:var(--panel);color:var(--fg);border:1px solid var(--border);border-radius:10px;outline:none}.answer-input:focus{border-color:var(--accent)}.audio-btn{font-size:40px;width:84px;height:84px;border-radius:50%;border:1px solid var(--border);background:var(--panel)}.choices{display:flex;flex-direction:column;gap:10px;width:min(560px,90vw)}.choice{display:flex;align-items:center;gap:12px;padding:12px 16px;border:1px solid var(--border);border-radius:10px;background:var(--panel);text-align:left;font-size:20px}.choice .num{flex:none;width:26px;height:26px;display:grid;place-items:center;border-radius:6px;background:var(--panel-2);font-size:14px;color:var(--muted)}.choice.correct{border-color:var(--good);background:#16271d}.choice.wrong{border-color:var(--bad);background:#2a1819}.reveal{width:min(560px,92vw);background:var(--panel);border:1px solid var(--border);border-radius:12px;padding:18px 20px}.reveal .surface{font-size:40px;font-weight:700}.reveal .reading{font-size:24px;color:var(--accent);margin-top:2px}.reveal .meaning{font-size:20px;margin-top:8px}.reveal .pos{font-size:14px;color:var(--muted)}.reveal .yours{margin-top:12px;padding-top:12px;border-top:1px dashed var(--border);font-size:16px}.reveal .yours .val{font-size:22px}.reveal .yours .ok{color:var(--good)}.reveal .yours .ng{color:var(--bad)}.rating-bar{display:flex;gap:8px}.rate{display:flex;flex-direction:column;align-items:center;gap:2px;padding:8px 14px;border-radius:9px;border:1px solid var(--border);background:var(--panel-2);min-width:78px}.rate .lbl{font-size:14px}.rate .sub{font-size:11px;color:var(--muted)}.rate.again{border-color:var(--bad)}.rate.hard{border-color:var(--warn)}.rate.good{border-color:var(--good)}.rate.easy{border-color:var(--accent)}.done-screen{text-align:center;display:flex;flex-direction:column;gap:14px;align-items:center}.big-num{font-size:56px;font-weight:700}.actions{display:flex;gap:10px;flex-wrap:wrap;justify-content:center}.btn.dunno{border-color:var(--warn);color:var(--warn)}.rate .k{display:inline-block;margin-right:4px;opacity:.55;font-size:.85em}.rate.sel{outline:2px solid currentColor;outline-offset:1px}.rating-bar{flex-wrap:wrap;justify-content:center}@media (max-width: 640px){.kbd-only{display:none!important}.app-shell{padding:12px}.lesson-grid{grid-template-columns:repeat(5,1fr);gap:6px}.lesson-cell{padding:8px 2px 6px}.prompt-jp{font-size:40px}.prompt-cn{font-size:26px}.answer-input{font-size:24px;width:92vw}.card-area{justify-content:flex-start;padding-top:10px;overflow-y:auto;gap:16px}.rate{flex:1 1 42%;min-width:0;padding:12px 8px}.choice{font-size:18px;padding:14px 16px}.btn,.pill{padding:10px 16px}.audio-btn{width:96px;height:96px;font-size:44px}}