:root{font-family:system-ui,Avenir,Helvetica,Arial,sans-serif;line-height:1.5;font-weight:400;color-scheme:light dark;color:#2f3437;background-color:#f8f9fa;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}*{box-sizing:border-box}html{min-width:320px}body{margin:0;min-height:100vh;display:flex;flex-direction:column;align-items:center;overflow-x:hidden}#app{width:100%;margin:0 auto;padding:22px 20px 10px;text-align:center;display:flex;flex-direction:column;gap:14px}h1{font-size:2.2rem;line-height:1.1;margin:0 0 .25rem}#game-controls-top{display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:10px}#game-controls-top label{font-weight:600}select,button{min-height:44px;font:inherit}select{max-width:100%;border:1px solid #b8c2cc;border-radius:8px;padding:.55rem 2rem .55rem .75rem;background-color:#fff;color:#2f3437}#question-display{min-height:2rem;font-size:1.35rem;font-weight:700;overflow-wrap:anywhere}#numberline-container{width:100%;border:1px solid #c7ccd1;border-radius:8px;background:#fff}#numberline-svg{display:block;width:100%;min-height:150px;touch-action:none;-webkit-user-select:none;user-select:none}#controls{display:flex;flex-wrap:wrap;justify-content:center;gap:10px;margin:8px 0 2px}button{border-radius:8px;border:1px solid #c4ccd4;padding:.65em 1.2em;font-weight:600;cursor:pointer;transition:border-color .2s,background-color .2s,transform .2s;background-color:#edf1f4;color:#2f3437}button:hover{border-color:#3273a8;background-color:#e5eef5}button:active{transform:translateY(1px)}button:focus,button:focus-visible,select:focus,select:focus-visible{outline:3px solid #7ab6e4;outline-offset:2px}#feedback-area{width:100%;max-width:72ch;align-self:center;margin-top:4px;padding:10px;border-radius:6px;min-height:2.75rem}#feedback-area.info{background-color:#e7f3ff;color:#00529b;border:1px solid #b8dcfc}#feedback-area.success{background-color:#d4edda;color:#155724;border:1px solid #c3e6cb}#feedback-area.warning{background-color:#fff3cd;color:#856404;border:1px solid #ffeeba}#feedback-area.error{background-color:#f8d7da;color:#721c24;border:1px solid #f5c6cb}#score-display{font-weight:700;font-size:1.2rem}.source-link{width:100%;margin:0 auto 18px;padding:0 20px;text-align:center;font-size:1rem}.source-link a{color:#1d638f}.tick text{fill:currentColor}.tick.major line{stroke:#333}.tick.minor line{stroke:#9aa3aa}.axis-line{stroke:#333}.draggable-marker{touch-action:none}.draggable-marker line,.draggable-marker circle{stroke:#d9534f;fill:#d9534f}.feedback-line-correct{stroke:#3f8f52}.feedback-text-correct{fill:#3f8f52}.feedback-text-user{fill:#d9534f}@media (max-width: 640px){#app{padding:14px 10px 8px;gap:10px}h1{font-size:1.55rem;margin-bottom:0}#game-controls-top{justify-content:stretch;gap:6px;text-align:left}#game-controls-top label{flex-basis:100%}select{width:100%;padding-top:.7rem;padding-bottom:.7rem}#question-display{min-height:1.8rem;font-size:1.25rem}#numberline-container{border-radius:6px}#numberline-svg{min-height:170px}#controls{display:grid;grid-template-columns:1fr;gap:8px;margin:4px 0 0}button{width:100%;padding:.8em 1em}#feedback-area{min-height:2.5rem;padding:8px;font-size:.95rem}#score-display{font-size:1rem}.source-link{margin-bottom:12px;padding:0 10px;font-size:.9rem}}@media (min-width: 641px) and (max-width: 900px){#app{padding-right:16px;padding-left:16px}h1{font-size:1.9rem}}@media (max-height: 520px) and (orientation: landscape) and (min-width: 520px){#app{display:grid;grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:8px 12px;padding:8px 12px 6px}h1{grid-column:1;font-size:1.35rem;text-align:left;margin:0;white-space:nowrap}#game-controls-top{grid-column:2;justify-content:end;gap:8px;text-align:right}#game-controls-top label{flex-basis:auto;white-space:nowrap}select,button{min-height:38px}select{width:auto;max-width:11rem;padding-top:.42rem;padding-bottom:.42rem}#question-display,#numberline-container,#controls,#feedback-area,#score-display{grid-column:1 / -1}#question-display{min-height:1.45rem;font-size:1.1rem}#numberline-svg{min-height:118px}#controls{display:flex;flex-wrap:nowrap;gap:8px;margin:0}button{width:auto;padding:.45em .9em}#feedback-area{min-height:2rem;padding:6px 8px;font-size:.9rem}#score-display{font-size:.95rem}.source-link{display:none}}@media (prefers-color-scheme: dark){:root{color:#eceff1;background-color:#16191b}select,button,#numberline-container{background-color:#23282c;color:#eceff1}select,button,#numberline-container{border-color:#535d66}button:hover{border-color:#8ac5f4;background-color:#2b343b}.source-link a{color:#9ed1f4}.tick.major line,.axis-line{stroke:#d1d5d8}.tick.minor line{stroke:#737d86}.draggable-marker line,.draggable-marker circle{stroke:#e57373;fill:#e57373}}