:root { color-scheme: dark; background: black; }
body { margin: 0; min-width: 800px; min-height: 600px; height: 100vh; display: grid; place-items: center; }
.viewport { position: relative; width: 800px; height: 600px; }
canvas { display: block; width: 800px; height: 600px; }
canvas:focus { outline: none; }
.viewport:fullscreen { width: 100%; height: 100%; }
.browser-page { position: absolute; left: 0; top: 0; width: 800px; height: 564px; border: 0; background: white; }
.browser-page[hidden] { display: none; }
.zone-banner, .html-view { position: absolute; border: 0; background: white; }
.zone-banner[hidden], .html-view[hidden] { display: none; }
.text-input-host { position: absolute; left: 0; bottom: 0; width: 1px; height: 1px; padding: 0; border: 0; opacity: 0; pointer-events: none; resize: none; }