:root{font-family:Aptos,Segoe UI,sans-serif;color:#211d18;background:#fff;color-scheme:light;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;--ink: #211d18;--muted: #6f6f6f;--paper: #ffffff;--line: rgba(0, 0, 0, .16);--clay: #111111;--sage: #333333;--sand: #f1f1f1;--black: #050505;--panel: #101010;--panel-soft: #181818;--panel-line: rgba(255, 255, 255, .16);--panel-muted: #b7b7b7}*{box-sizing:border-box}html,body,#root{min-height:100%;margin:0}body{min-height:100vh;overflow:hidden;color:var(--ink);background:#fff}button,input{font:inherit}button{border:1px solid var(--line);border-radius:8px;background:#fff;color:var(--ink);cursor:pointer}button:disabled{opacity:.5;cursor:not-allowed}input{width:100%;border:1px solid var(--line);border-radius:8px;background:#fff;color:var(--ink);padding:.62rem .7rem}input[type=range]{padding:0;border:0;background:transparent;touch-action:auto}.physics-stage{position:relative;width:100vw;height:100vh;overflow:hidden;background-color:#fff;background-image:radial-gradient(circle,rgba(0,0,0,.16) 1px,transparent 1.2px);background-position:var(--grid-x, 0) var(--grid-y, 0);background-size:var(--grid-size, 34px) var(--grid-size, 34px)}.exercise-menu-screen{min-height:100vh;display:grid;place-items:center;padding:28px;background-color:#fff;background-image:radial-gradient(circle,rgba(0,0,0,.14) 1px,transparent 1.2px);background-size:34px 34px}.exercise-menu-shell{width:min(980px,100%);display:grid;gap:1.35rem}.exercise-menu-header{display:grid;gap:.35rem}.exercise-menu-header span{color:var(--muted);font-size:.9rem;font-weight:800}.exercise-menu-header h1{margin:0;font-family:Georgia,Times New 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minmax(0,1fr);align-items:center;gap:.55rem;min-height:46px;padding:.3rem;text-align:left;border-color:#ffffff29;background:var(--panel-soft);color:#fff}.asset-mini img{width:36px;height:36px;object-fit:cover;border-radius:50%}.asset-mini span{overflow:hidden;white-space:nowrap;text-overflow:ellipsis}@media (max-width: 760px){.physics-box{max-width:calc(100vw - 24px)}.viewport-status span{display:none}.two-up,.action-grid{grid-template-columns:1fr}.menu-return{right:72px;max-width:calc(100vw - 144px);padding:0 .85rem;overflow:hidden;white-space:nowrap;text-overflow:ellipsis}.addition-layout{grid-template-columns:1fr}.operation-switcher{grid-template-columns:repeat(2,minmax(0,1fr))}.addition-board{width:100%}.addition-row{grid-template-columns:30px 24px repeat(var(--addition-columns),44px)}.addition-cell{width:44px;height:44px;font-size:1.25rem}.division-answer-row{grid-template-columns:72px repeat(var(--addition-columns),44px)}.division-house-row{grid-template-columns:72px minmax(0,1fr)}.division-divisor{width:62px;height:44px}.division-house{grid-template-columns:repeat(var(--addition-columns),44px)}.division-work{margin-left:72px}.division-work-row{grid-template-columns:24px repeat(var(--division-work-cells),44px)}.division-work-sign{min-height:44px}}