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8px;font-size:1rem;line-height:1.65}.rectangle-area-board-wrap{max-width:620px;margin:12px auto 18px;padding:40px 64px 54px}.rectangle-area-grid{-webkit-user-select:none;user-select:none;background:#fff;border:2px solid #8ca7e4;width:100%;display:grid;position:relative;overflow:visible;box-shadow:0 12px 24px #3052a51a}.rectangle-area-cell{background:#fbfcff;border-bottom:1px dashed #b9c8ea;border-right:1px dashed #b9c8ea;min-width:0;min-height:0;transition:background .13s;display:block}.rectangle-area-cell.is-filled{background:#dce8ff}.rectangle-area-selection{z-index:1;box-sizing:border-box;pointer-events:none;background:#517fe329;border:3px solid #3157d5;min-width:0;min-height:0;transition:left .13s,top .13s,width .13s,height .13s;position:absolute}.rectangle-area-length-label,.rectangle-area-width-label{color:#17306d;white-space:nowrap;background:#fff;border-radius:999px;padding:3px 8px;font-size:.78rem;font-weight:800;line-height:1.25;display:block;position:absolute;box-shadow:0 2px 6px #1d397a24}.rectangle-area-length-label{top:-1.9rem;left:50%;transform:translate(-50%)}.rectangle-area-width-label{top:50%;left:-4.45rem;transform:translateY(-50%)}.rectangle-area-handle{z-index:2;box-sizing:border-box;color:#0000;width:44px;height:44px;box-shadow:none;cursor:grab;pointer-events:auto;touch-action:none;background:0 0;border:0;border-radius:0;display:block;position:absolute}.rectangle-area-handle:focus-visible{outline-offset:3px;outline:3px solid #ff8a4c}.rectangle-area-handle:active{cursor:grabbing;box-shadow:none;background:0 0}.rectangle-area-length-handle{cursor:ew-resize;top:50%;right:-24px;transform:translateY(-50%)}.rectangle-area-width-handle{cursor:ns-resize;bottom:-24px;left:50%;transform:translate(-50%)}.rectangle-area-corner-handle{z-index:3;box-sizing:border-box;width:32px;height:32px;box-shadow:none;pointer-events:auto;touch-action:none;background:0 0;border:0;position:absolute}.rectangle-area-corner-handle:focus-visible{outline-offset:3px;outline:3px solid #ff8a4c}.rectangle-area-top-left-corner-handle{cursor:nwse-resize;top:-17px;left:-17px}.rectangle-area-top-right-corner-handle{cursor:nesw-resize;top:-17px;right:-17px}.rectangle-area-bottom-left-corner-handle{cursor:nesw-resize;bottom:-17px;left:-17px}.rectangle-area-bottom-right-corner-handle{cursor:nwse-resize;bottom:-17px;right:-17px}.rectangle-area-formula{color:#17306d;background:#f5f8ff;border:1px solid #9eb2ec;border-radius:14px;max-width:580px;margin:0 auto 14px;padding:12px 16px;font-size:1rem;line-height:1.65}.rectangle-area-controls{gap:10px;max-width:560px;margin:0 auto 16px;display:grid}.rectangle-area-control-group{color:#344460;text-align:left;background:#fff;border:1px solid #d1dbf2;border-radius:14px;grid-template-columns:minmax(92px,1fr) repeat(2,minmax(112px,auto));align-items:center;gap:8px;padding:8px;font-weight:800;display:grid}.rectangle-area-control-group button{color:#24499c;background:#f6f8ff;border-color:#8fa9e7;min-height:44px;font-weight:800}.rectangle-area-control-group button:active{background:#eaf0ff;transform:translateY(1px)}.clock-face{aspect-ratio:1;cursor:grab;touch-action:none;-webkit-user-select:none;user-select:none;background:radial-gradient(circle,#fff 0 8%,#f8fbff 9% 100%);border:12px solid #a7d5f0;border-radius:50%;width:min(72vw,300px);margin:22px auto;position:relative;box-shadow:inset 0 0 0 2px #3157d5,0 12px 26px #3157d529}.clock-face.is-turning{cursor:grabbing;box-shadow:inset 0 0 0 2px #3157d5,0 0 0 6px #ff8a4c29,0 12px 26px #3157d529}.clock-number{color:#17306d;pointer-events:none;place-items:center;width:1.6rem;height:1.6rem;margin:-.8rem;font-weight:800;display:grid;position:absolute;top:50%;left:50%}.clock-hand{transform-origin:50% 100%;pointer-events:none;border-radius:999px 999px 0 0;width:8px;position:absolute;bottom:50%;left:calc(50% - 4px)}.minute-hand{background:#3157d5;height:36%}.hour-hand{background:#ff7a3d;height:27%;transition:transform .18s}.clock-pin{pointer-events:none;background:#17306d;border:3px solid #fff;border-radius:50%;width:18px;height:18px;position:absolute;top:calc(50% - 9px);left:calc(50% - 9px)}.clock-gesture-hint{color:#56647a;max-width:420px;margin:-8px auto 16px;font-size:.92rem}.clock-range-label{color:#344460;gap:6px;max-width:420px;margin:0 auto 16px;display:grid}.clock-range{min-width:0!important;margin-top:0!important}.fallback-card{background:#fff;border:1px solid #f2c98f;border-radius:20px;padding:24px;box-shadow:0 16px 48px #7d4b181a}.fallback-card h2,.fallback-card li+li{margin-top:8px}@media (width<=600px){.runtime{padding:24px 14px}.explorer{border-radius:18px;padding:18px}.tile-board{grid-template-columns:1fr}.balance-pan{width:110px;font-size:1rem}.part-whole-model{padding:14px}.model-bar,.model-empty-parts{height:52px}.model-total-label,.model-parts-label{font-size:.84rem}.solid-stage{border-radius:16px;height:310px}.solid-dimension,.solid-render-badge,.solid-compass{padding:5px 8px;font-size:.72rem}.solid-height{top:58%}.counter-frame{grid-template-columns:repeat(5,minmax(34px,46px));gap:6px;padding:10px}.clock-face{width:min(76vw,270px)}.array-model-row{grid-template-columns:56px minmax(0,1fr);gap:8px;padding:8px}.array-model-dots{gap:5px}.rectangle-area-board-wrap{padding:38px 54px 50px}.rectangle-area-control-group{text-align:center;grid-template-columns:1fr 1fr}.rectangle-area-control-group>span{grid-column:1/-1}.number-line-marker.is-minor:not(.is-start):not(.is-end){display:none}.number-line-controls button{min-width:0}.factor-board{gap:8px}.factor-card{min-width:128px;padding:12px}.solid-builder-layout{grid-template-columns:1fr}.solid-builder-grid{grid-template-columns:repeat(2,minmax(64px,1fr))}}@media (prefers-reduced-motion:reduce){*,:before,:after{scroll-behavior:auto!important;transition:none!important}}@keyframes slot-invitation{0%,to{transform:scale(1)}50%{transform:scale(1.035)}}@keyframes discovery-in{0%{opacity:0;transform:translateY(8px)scale(.98)}to{opacity:1;transform:translateY(0)scale(1)}}.money-explorer{text-align:center}.money-target{color:#17306d;font-size:1.05rem}.money-tray{background:#f6f8ff;border:2px dashed #9eb2ec;border-radius:14px;flex-wrap:wrap;justify-content:center;gap:8px;min-height:56px;margin:16px 0;padding:12px;display:flex}.money-coin{color:#7a4b12;background:#ffe9b8;border:2px solid #d8a13e;border-radius:999px;justify-content:center;align-items:center;min-width:56px;min-height:40px;padding:4px 10px;font-weight:600;display:inline-flex}.money-empty{color:#8a97ad;align-self:center}.money-total{color:#33415c}.money-controls{justify-content:center}.shape-sort-explorer{text-align:center}.sort-items{flex-wrap:wrap;justify-content:center;gap:10px;margin:16px 0;display:flex}.sort-item{color:#17306d;cursor:pointer;touch-action:manipulation;background:#edf2ff;border:2px solid #9eb2ec;border-radius:12px;min-height:44px;padding:8px 14px;font-size:1rem}.sort-item.is-selected{background:#dfe8ff;border-color:#3157d5;box-shadow:0 0 0 3px #3157d52e}.sort-item.is-placed{color:#56647a;cursor:default;background:0 0;border-style:dashed}.sort-groups{flex-wrap:wrap;justify-content:center;gap:14px;margin:8px 0 4px;display:flex}.sort-bin{background:#fbfcff;border:2px solid #cdd8f2;border-radius:16px;flex:150px;max-width:220px;padding:10px}.sort-bin-button{color:#17306d;cursor:pointer;touch-action:manipulation;background:#edf2ff;border:1px solid #9eb2ec;border-radius:12px;width:100%;min-height:44px;font-weight:600;display:block}.sort-bin-items{flex-wrap:wrap;justify-content:center;gap:6px;min-height:34px;margin-top:8px;display:flex}.sort-placed{color:#18763a;background:#eaf9ef;border:1px solid #9ed8b2;border-radius:999px;align-items:center;padding:4px 10px;display:inline-flex}