:root{--bg:#e9edf0;--panel:#fff;--ink:#1b2226;--muted:#56636c;--line:#d0d8de;--chip:#dde4ea;--accent:#1864ab;--accent-ink:#fff;--good:#2b8a3e;--bad:#c92a2a;--board:#fff;--f-ui:"Atkinson Hyperlegible", "IBM Plex Sans Arabic", system-ui, -apple-system, sans-serif;--f-brand:"Kalam", "Comic Sans MS", cursive;--f-board:"Patrick Hand", "IBM Plex Sans Arabic", "Comic Sans MS", sans-serif}@media (prefers-color-scheme:dark){:root{--bg:#13181b;--panel:#1d2428;--ink:#e5ebee;--muted:#9aa7b0;--line:#2e393f;--chip:#283237;--accent:#4c9be8;--accent-ink:#0b1620;--good:#51cf66;--bad:#ff8787;--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark}}*{box-sizing:border-box}[hidden]{display:none!important}html,body{margin:0}body{background:var(--bg);color:var(--ink);font:16px/1.45 var(--f-ui);padding:env(safe-area-inset-top,0px) max(12px, env(safe-area-inset-right,0px)) 24px max(12px, env(safe-area-inset-left,0px))}button,input,select{font:inherit;color:inherit}button{cursor:pointer;border:1px solid var(--line);background:var(--panel);border-radius:8px;min-height:40px;padding:8px 14px}button:disabled{opacity:.5;cursor:default}button.primary{background:var(--accent);color:var(--accent-ink);border-color:var(--accent);font-weight:700}button.secondary{border-color:var(--accent);color:var(--accent);font-weight:700}button.ghost{color:var(--muted);background:0 0;border-color:#0000}button[aria-pressed=true]{background:var(--chip);font-weight:700}:focus-visible{outline:3px solid var(--accent);outline-offset:2px}select,input[type=text],input:not([type]){border:1px solid var(--line);background:var(--panel);border-radius:8px;min-height:40px;padding:8px 10px}.top{flex-wrap:wrap;align-items:center;gap:8px 14px;padding:10px 0;display:flex}.brand{font:700 26px/1 var(--f-brand);color:var(--accent)}.brand.big{font-size:40px}.problem{color:var(--muted);align-items:center;gap:8px;display:flex}.problem select{max-width:min(70vw,420px)}#own{flex:260px;max-width:520px}.grow{flex:1}.layout{grid-template-columns:minmax(0,1fr);gap:16px;min-width:min(100%,560px);max-width:min(1100px,143vh - 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