index.html

<!doctype html>

<title>bad.shoes</title>

<style>
body, html {
	margin: 0;
	padding: 0;
	width: 100%;
	height: 100%;
	overflow: hidden;
}
</style>

<div id="player"></div>

<script>
var tag = document.createElement('script');
tag.src = "https://www.youtube.com/iframe_api";
var firstScriptTag = document.getElementsByTagName('script')[0];
firstScriptTag.parentNode.insertBefore(tag, firstScriptTag);

var player;
function onYouTubeIframeAPIReady() {
	player = new YT.Player('player', {
		height: '100%',
		width: '100%',
		videoId: 'wCF3ywukQYA',
		playerVars: {
			controls: 0,
			disablekb: 1,
			start: 120,
			end: 126,
			autoplay: 1,
			iv_load_policy: 3
		},
		events: {
			onReady: onPlayerReady
		}
	})
}
function onPlayerReady() {
	var justDidSeek = true;
	setInterval(function() {
		var time = player.getCurrentTime();
		if (!justDidSeek && (time >= 125.5 || time < 120)) {
			player.seekTo(120, true);
			player.playVideo();
			justDidSeek = true;
		} else {
			justDidSeek = false;
		}
	}, 100);
}
</script>