:root { color-scheme: dark; background: #000; color: #aaa; }
* { box-sizing: border-box; }
html, body { margin: 0; min-height: 100%; background: #000; }
body { min-height: 100vh; display: grid; grid-template-columns: minmax(0, 1fr); place-items: center; font-family: 'Courier New', Courier, monospace; }
main { min-width: 0; width: min(100%, 1000px); padding: 24px 10px; }
#display-wrap { width: 100%; overflow: hidden; margin: 0 auto 24px; }
#display { width: 960px; height: 600px; font: 20px/24px 'Courier New', Courier, monospace; white-space: pre; background: #000; outline: none; user-select: none; transform-origin: top left; }
.line { height: 24px; display: flex; }
.cell { display: inline-block; width: 12px; height: 24px; flex: 0 0 12px; text-align: center; overflow: hidden; }
nav { display: flex; flex-wrap: wrap; justify-content: center; gap: 6px 18px; }
button { font: inherit; color: #aaa; background: #000; border: 1px solid #333; padding: 6px 10px; cursor: pointer; touch-action: manipulation; }
button:hover, button:focus-visible { color: #fff; border-color: #aaa; outline: none; }
.arrows { margin-top: 12px; }
.arrows button { min-width: 42px; }
#hint { text-align: center; font-size: 12px; margin: 16px 0 0; color: #777; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); border: 0; }
@media (max-width: 600px) { main { padding: 12px 6px; } nav { gap: 6px; font-size: 12px; } }