html, body { width:100%; height:100%; margin:0; overflow:hidden; background:#0b0b0c; }
body { font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif; }
#fluid { display:block; width:100%; height:100%; touch-action:none; }
.hint { position:fixed; left:50%; bottom:18px; transform:translateX(-50%); padding:7px 10px; border:1px solid rgba(255,255,255,.18); border-radius:999px; color:rgba(255,255,255,.7); background:rgba(0,0,0,.24); backdrop-filter:blur(8px); font-size:12px; letter-spacing:.08em; text-transform:uppercase; pointer-events:none; transition:opacity .4s ease; }
.hint.hidden { opacity:0; }