Disco Flash
page decoration 1997 still worksFlashes the background between two colours. Put this on your entry page. Please do not.
In 2026: Works. Genuinely a seizure risk above about 3 flashes per second, so this version is throttled and stops after 12 flashes.
Where it came from: Origin unclear, and probably better left that way. Wikipedia ↗
<script language="JavaScript">
var on = false, flashes = 0;
var disco = setInterval(function () {
on = !on;
document.body.style.backgroundColor = on ? "#FF00FF" : "#00FFFF";
if (++flashes > 12) {
clearInterval(disco);
document.body.style.backgroundColor = "";
}
}, 350);
</script>