:root{color-scheme:light;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:#171717;background:#fff;font-size:16px}*{box-sizing:border-box}body{margin:0;line-height:1.6}main{max-width:440px;margin:auto;padding:18px 18px max(24px,env(safe-area-inset-bottom))}header{display:flex;align-items:center;justify-content:space-between;gap:12px}h1{font-size:24px;letter-spacing:2px;margin:0}header span{font-size:12px;color:#666}h2{font-size:17px;margin:0}button{font:inherit;color:inherit;cursor:pointer;touch-action:manipulation;-webkit-tap-highlight-color:transparent;border:1px solid #d5d5d5;border-radius:8px;background:#f5f5f5;min-height:48px}button:focus-visible,summary:focus-visible{outline:3px solid #666;outline-offset:3px}button:active:not(:disabled){background:#ddd}button:disabled{color:#999;background:#f6f6f6;border-color:#e9e9e9;cursor:default}details{margin:10px 0 18px;font-size:14px;color:#555;border-bottom:1px solid #e5e5e5;padding-bottom:8px}summary{cursor:pointer;min-height:36px;display:flex;align-items:center;touch-action:manipulation}summary:after{content:'＋';margin-left:auto}details[open] summary:after{content:'−'}details p{margin:10px 0}.progress{display:flex;justify-content:space-between;align-items:center;gap:8px;font-size:14px;margin-bottom:12px}.progress span{color:#666;font-size:12px}.slots{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px}.slot{height:64px;border:1px solid #ccc;border-radius:8px;display:grid;place-items:center;font:32px ui-monospace,monospace;background:#fafafa}.slot.active{border:2px solid #171717;background:#fff}#message{font-size:14px;color:#555;margin:10px 0;min-height:23px}.keyboard{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px}.keyboard button{height:52px;font-size:23px;font-variant-numeric:tabular-nums}.keyboard .edit{font-size:14px;background:white}.primary{background:#171717;color:#fff;border-color:#171717;font-weight:600;width:100%;margin-top:10px;min-height:50px}.primary:active:not(:disabled){background:#444}#result{border-top:1px solid #ddd;margin-top:16px;padding-top:16px}#result h2{font-size:23px}#answer{margin:8px 0}.history{margin-top:25px}.legend{font-size:12px;color:#666;margin:4px 0 12px}table{width:100%;border-collapse:collapse;text-align:center}th{font-size:12px;color:#666;font-weight:500;border-bottom:1px solid #ddd;padding:8px 3px}td{padding:10px 3px;border-bottom:1px solid #eee;font-variant-numeric:tabular-nums}td:nth-child(2){font:22px ui-monospace,monospace;letter-spacing:6px}tbody tr:first-child{background:#f4f4f4}#empty{font-size:14px;color:#777;text-align:center;padding:12px}.restart{display:block;background:white;margin:20px auto 0;padding:8px 20px;color:#666;font-size:14px}#storage-warning{font-size:14px}dialog{border:1px solid #ccc;border-radius:12px;padding:22px;width:calc(100% - 32px);max-width:400px;color:#171717;background:#fff}dialog::backdrop{background:#0006}.dialog-actions{display:flex;gap:10px}.dialog-actions button{flex:1;margin:0}dialog h2{font-size:18px}dialog p{font-size:14px}[hidden]{display:none!important}@media(max-width:350px){main{padding-left:14px;padding-right:14px}header span{font-size:12px}.slots{gap:8px}}@media(max-height:700px){main{padding-top:12px}details{margin-bottom:12px}.slot{height:54px}.keyboard button{height:48px}}

.flying-digit{position:fixed;left:0;top:0;width:0;height:0;display:flex;align-items:center;justify-content:center;font:32px ui-monospace,monospace;pointer-events:none;z-index:20;color:#171717;will-change:transform}
.feedback-overlay{position:fixed;inset:0;display:grid;place-items:center;z-index:30;pointer-events:none;padding:24px}
.feedback-card{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:8px;background:#171717;color:white;border-radius:18px;padding:32px 44px;box-shadow:0 16px 65px #0003;min-width:220px}
.feedback-card strong{font-size:42px;letter-spacing:2px;line-height:1.2}.feedback-card span{font-size:26px;letter-spacing:3px}
@media(prefers-reduced-motion:reduce){.flying-digit{display:none}}

.home-nav{max-width:460px;margin:0 auto;padding:12px 18px 0}.home-nav a{display:inline-flex;align-items:center;min-height:44px;color:#555;font-size:14px;text-decoration:none;touch-action:manipulation}