html, body { margin: 0; width: 100%; height: 100%; overflow: hidden; background: #10141d; color: #fff; font: 15px system-ui, sans-serif; }
canvas { display: block; }
#loading, #error { position: fixed; z-index: 2; left: 50%; top: 50%; transform: translate(-50%, -50%); padding: 12px 16px; border-radius: 8px; background: #10141ddd; }
#error { max-width: min(85vw, 600px); color: #ffd3d3; }
#help { position: fixed; z-index: 1; left: 50%; bottom: 18px; transform: translateX(-50%); padding: 8px 12px; border-radius: 8px; background: #10141dbb; text-align: center; pointer-events: none; }
button#VRButton { border: 0; border-radius: 5px; }
#cardboardButton { position: fixed; z-index: 3; right: 18px; bottom: 18px; border: 0; border-radius: 5px; padding: 12px 16px; background: #fff; color: #111; font: 600 14px system-ui, sans-serif; }
body.cardboard #help { display: none; }