:root{color-scheme:light dark;--bg: #f6f7f9;--bg-tint: rgba(99, 102, 241, .07);--surface: #ffffff;--surface-2: #f2f3f6;--surface-hi: #ffffff;--ink: #0d1117;--ink-soft: #5a6373;--ink-faint: #8d95a3;--line: #e5e7ec;--line-strong: #d5d8e0;--accent: #4f46e5;--accent-hi: #6366f1;--accent-ink: #ffffff;--accent-soft: #eef0ff;--accent-line: #d8dbfb;--green: #047857;--green-soft: #e7f6ef;--green-line: #a9ddc6;--amber: #b45309;--red: #be123c;--red-soft: #fdeef1;--red-line: #f2bccb;--radius-sm: 10px;--radius: 14px;--radius-lg: 18px;--radius-xl: 24px;--shadow-sm: 0 1px 2px rgba(13, 17, 23, .05), 0 1px 1px rgba(13, 17, 23, .03);--shadow: 0 1px 2px rgba(13, 17, 23, .05), 0 6px 16px -8px rgba(13, 17, 23, .14);--shadow-lg: 0 1px 2px rgba(13, 17, 23, .05), 0 18px 40px -20px rgba(13, 17, 23, .28);--shadow-accent: 0 8px 24px -12px rgba(79, 70, 229, .65);--ease: cubic-bezier(.2, 0, 0, 1);--dur: .16s}@media(prefers-color-scheme:dark){:root{--bg: #0a0b0e;--bg-tint: rgba(99, 102, 241, .16);--surface: #15171c;--surface-2: #1d2027;--surface-hi: #1a1d23;--ink: #eef1f6;--ink-soft: #9aa3b2;--ink-faint: #6e7787;--line: #262a33;--line-strong: #333846;--accent: #818cf8;--accent-hi: #a5b4fc;--accent-ink: #0b0d16;--accent-soft: rgba(129, 140, 248, .14);--accent-line: rgba(129, 140, 248, .32);--green: #34d399;--green-soft: rgba(52, 211, 153, .13);--green-line: rgba(52, 211, 153, .36);--amber: #fbbf24;--red: #fb7185;--red-soft: rgba(251, 113, 133, .13);--red-line: rgba(251, 113, 133, .36);--shadow-sm: 0 1px 2px rgba(0, 0, 0, .5);--shadow: 0 1px 2px rgba(0, 0, 0, .5), 0 6px 16px -8px rgba(0, 0, 0, .7);--shadow-lg: 0 1px 2px rgba(0, 0, 0, .5), 0 18px 40px -20px rgba(0, 0, 0, .9);--shadow-accent: 0 8px 24px -12px rgba(129, 140, 248, .5)}}*{margin:0;padding:0;box-sizing:border-box}html,body{height:100%}body{font-family:-apple-system,BlinkMacSystemFont,SF Pro Text,Hiragino Sans,Hiragino Kaku Gothic ProN,Noto Sans 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var(--ease)}.pin-gate{flex:1;min-height:0;overflow-y:auto;display:grid;place-items:center;padding:24px;padding-top:max(24px,env(safe-area-inset-top))}.pin-card{width:100%;max-width:340px;text-align:center;display:flex;flex-direction:column;gap:14px;padding:32px 24px;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-xl);box-shadow:var(--shadow-lg)}.pin-logo{font-size:44px;line-height:1}.pin-title{font-size:22px;font-weight:700}.pin-desc{color:var(--ink-soft);font-size:13px;margin-top:-6px}.pin-input{width:100%;min-height:56px;padding:14px;font-size:26px;text-align:center;letter-spacing:12px;text-indent:12px;border:1px solid var(--line-strong);border-radius:var(--radius);background:var(--surface-2);color:var(--ink);outline:none;transition:border-color var(--dur) var(--ease),box-shadow var(--dur) var(--ease)}.pin-input:focus{border-color:var(--accent);background:var(--surface);box-shadow:0 0 0 4px 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var(--line);border-radius:var(--radius);box-shadow:var(--shadow-sm)}.tool-btn:active{transform:scale(.98)}.tool-btn:disabled{opacity:.35;box-shadow:none}.tool-btn-on{color:var(--accent);background:var(--accent-soft);border-color:var(--accent-line)}.tool-icon{font-size:14px;line-height:1}.quiz{margin-top:10px;min-height:0;overflow-y:auto}.choice-list{list-style:none;display:flex;flex-direction:column;gap:8px}.choice{width:100%;min-height:48px;display:flex;align-items:center;gap:10px;padding:11px 14px;text-align:left;font-size:14px;line-height:1.5;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow-sm)}.choice:active{transform:scale(.99);border-color:var(--accent-line);background:var(--accent-soft)}.choice:disabled{cursor:default}.choice-text{flex:1;overflow-wrap:anywhere}.choice-mark{font-size:15px;font-weight:700;flex-shrink:0}.choice-correct{background:var(--green-soft);border-color:var(--green-line);color:var(--green);font-weight:650;opacity:1}.choice-wrong{background:var(--red-soft);border-color:var(--red-line);color:var(--red);font-weight:650;opacity:1}.quiz-result{margin-top:14px;display:flex;flex-direction:column;gap:10px;align-items:center}.quiz-verdict{font-size:14px;font-weight:700}.quiz-ok{color:var(--green)}.quiz-ng{color:var(--red)}.quiz-next{width:100%}.grade-row{display:grid;grid-template-columns:1fr 1fr 1fr;gap:10px;margin-top:12px;min-height:76px}.grade-btn{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:3px;padding:10px 8px;border-radius:var(--radius);background:var(--surface);border:1px solid var(--line);box-shadow:var(--shadow-sm);font-size:13px;font-weight:700}.grade-btn:active{transform:scale(.97);box-shadow:none}.grade-emoji{font-size:22px;line-height:1.2}.grade-again{color:var(--red)}.grade-hard{color:var(--amber)}.grade-easy{color:var(--green)}.study-done{align-items:center;justify-content:center;gap:12px;text-align:center}.done-emoji{font-size:52px;line-height:1}.done-text{font-size:17px;font-weight:700}.done-sub{color:var(--ink-soft);font-size:13px;margin-top:-6px}