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0 100%}.arithmetic-timeline input{width:100%;min-height:44px;accent-color:var(--blue);cursor:pointer}.arithmetic-timeline span{color:var(--muted);margin-left:auto}.arithmetic-problem{background:#fff;border-radius:12px;padding:16px;line-height:1.9}.arithmetic-problem p{margin-top:0}.arithmetic-problem ul{padding-left:20px}.arithmetic-problem strong{color:var(--blue)}.relation-analysis{margin-top:20px}.relation-chain{gap:10px;padding:0;list-style:none;display:grid}.relation-chain li{border:1px solid var(--border);background:#fff;border-radius:10px;gap:12px;padding:14px;display:flex}.relation-chain li>span{color:var(--blue);background:var(--blue-soft);text-align:center;border-radius:50%;min-width:28px;height:28px;line-height:28px}.relation-chain p{margin:5px 0 0;font-size:14px;line-height:1.7}.expression-choices{border:0;gap:8px;margin:20px 0;padding:0;display:grid}.expression-choices legend{padding:0 0 10px;font-size:14px}.expression-choices button{text-align:left;overflow-wrap:anywhere;background:#fff;border:1px solid #cbd5ee;border-radius:10px;justify-content:start;min-height:44px}.expression-choices button:hover{border-color:var(--blue);background:var(--blue-soft)}.quantity-summary{color:var(--muted);margin-top:20px;font-size:13px}.arithmetic-bar{border:1px solid #cbd5ee;border-radius:8px;height:38px;display:flex;overflow:hidden}.arithmetic-bar span{opacity:.42;border-right:2px solid #fff}.arithmetic-bar .revealed{opacity:1}.arithmetic-player [data-part="0"]{background:#3563e9}.arithmetic-player [data-part="1"]{background:#c38b2c}.arithmetic-player [data-part="2"]{background:#4c9679}.quantity-summary ul{flex-wrap:wrap;gap:12px;padding:0;list-style:none;display:flex}.quantity-summary i{border-radius:2px;width:10px;height:10px;margin-right:6px;display:inline-block}.bracket-comparison{margin-top:18px;font-size:14px;line-height:1.9}.bracket-comparison summary{cursor:pointer;min-height:44px;color:var(--blue);padding:10px 0}.arithmetic-static{border-top:1px solid var(--border);margin-top:20px;padding-top:8px;line-height:1.8}.arithmetic-static li{margin-bottom:16px}@media (width>=768px) and (width<=1100px){.arithmetic-player,.arithmetic-stage{padding:18px}.arithmetic-heading{flex-wrap:wrap}}.large-number-player{min-width:0;padding:24px}.large-number-player select,.large-number-player input:not([type=range]){max-width:100%;min-height:44px;color:var(--ink);font:inherit;background:#fff;border:1px solid #cbd5ee;border-radius:9px;padding:8px 10px}.large-number-player .button{min-height:44px}.large-number-player :is(button,input,select):focus-visible{outline:3px solid var(--blue);outline-offset:3px}.large-number-stage{border:1px solid var(--border);background:#f7f9ff;border-radius:14px;min-width:0;margin-top:20px;padding:20px}.large-number-stage h3{margin:0 0 16px;font-size:17px}.number-input-form{flex-wrap:wrap;align-items:end;gap:10px;margin:18px 0 8px;display:flex}.number-input-form label{flex:180px;gap:7px;min-width:0;font-size:13px;display:grid}.number-input-form input{width:100%}.number-tool-note{color:var(--muted);font-size:12px;line-height:1.8}.number-mode-buttons{margin:18px 0}.number-banner{border:1px solid var(--border);background:#fff;border-radius:10px;gap:8px;margin-bottom:18px;padding:16px;display:grid}.number-banner>span{color:var(--muted);font-size:12px}.number-banner>strong{font-variant-numeric:tabular-nums;letter-spacing:1px;overflow-wrap:anywhere;font-size:clamp(20px,2.1vw,29px)}.number-banner small{color:var(--muted);font-size:11px}.number-classes{grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:10px;display:grid}.number-classes section{background:#fff;border:1px solid #d5ddea;border-radius:10px;padding:10px}.number-classes h4{text-align:center;color:var(--muted);margin:0 0 10px;font-size:13px}.number-classes .active-number-class{border-color:var(--blue);box-shadow:0 0 0 1px var(--blue)}.digit-row{grid-template-columns:repeat(4,minmax(0,1fr));gap:3px;display:grid}.digit-card{min-width:44px;min-height:114px;color:var(--ink);cursor:pointer;background:#f4f6fb;border:1px solid #0000;border-radius:6px;place-items:center;gap:8px;padding:10px 0;display:grid}.digit-card small{white-space:nowrap;font-size:10px}.digit-card strong{font-variant-numeric:tabular-nums;font-size:24px}.digit-card>span{color:var(--muted);font-size:10px}.digit-card[data-selected=true]{border-color:var(--blue);background:var(--blue-soft)}.digit-card[data-focus=true]{box-shadow:inset 0 -3px #c38b2c}.digit-card:hover{background:var(--blue-soft)}.number-place-detail{background:#fff;border-radius:10px;margin-top:12px;padding:14px;font-size:13px;line-height:1.8}.number-place-detail>span{color:var(--muted);display:block}.number-place-detail p{margin:6px 0}.number-place-detail label{flex-wrap:wrap;align-items:center;gap:10px;display:flex}.number-readout{gap:8px;padding:16px;line-height:1.8;display:grid}.number-readout>span{color:var(--muted);font-size:12px}.number-readout strong{color:var(--blue);font-size:18px}.number-result{color:#2c7154;overflow-wrap:anywhere;background:#eaf5ef;border-radius:10px;margin-top:14px;padding:16px;font-size:21px;font-weight:700}.unit-exchange{background:#fff;border-radius:10px;flex-wrap:wrap;justify-content:center;align-items:center;gap:20px;margin:20px 0;padding:16px;line-height:1.8;display:flex}.unit-pile{grid-template-columns:repeat(5,36px);gap:5px;display:grid}.unit-pile span{background:var(--blue-soft);color:var(--blue);border:1px solid #cbd5ee;border-radius:5px;place-items:center;min-height:30px;font-size:11px;display:grid}.number-line{border:1px solid var(--border);background:#fff;border-radius:10px;margin-top:20px}.number-line svg{width:100%;height:auto;display:block}.number-line text{fill:var(--ink);font-variant-numeric:tabular-nums;font-size:20px}.range-probes{flex-wrap:wrap;gap:8px;margin-top:12px;display:flex}.range-probes p{flex-basis:100%;font-size:13px}.range-probes .button{background:#fff;border:1px solid #cbd5ee;font-size:12px}.writing-task{background:#edf2ff;border-radius:10px;margin-bottom:16px;padding:16px;line-height:1.8}.writing-task p{font-size:13px}.number-comparison{gap:12px;margin:20px 0;display:grid}.number-comparison>div{gap:8px;display:grid}.number-comparison span{color:var(--muted);font-size:12px}.number-comparison strong{flex-wrap:wrap;gap:3px;display:flex}.number-comparison i{font-variant-numeric:tabular-nums;padding:3px;font-size:24px;font-style:normal}.deciding-digit{background:#fff0d5;border-bottom:3px solid #c38b2c}.encoding-fields{flex-wrap:wrap;align-items:end;gap:10px;margin:16px 0;display:flex}.encoding-fields label{flex:100px;gap:8px;min-width:0;font-size:12px;display:grid}.encoding-fields input{width:100%}.encoding-segments{grid-template-columns:4fr 2fr 3fr;gap:8px;display:grid}.encoding-segments>div{background:#fff;border:1px solid #cbd5ee;border-radius:10px;place-items:center;gap:10px;padding:12px 4px;display:grid}.encoding-segments span{color:var(--muted);font-size:12px}.encoding-segments strong{color:var(--blue);font-variant-numeric:tabular-nums;letter-spacing:2px;font-size:clamp(19px,2.1vw,28px)}@media (width>=768px) and (width<=1100px){.large-number-player{padding:18px}.large-number-stage{padding:16px}}