mnako/worldclock.html

## worldclock.html
<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<style>
		html, body {
			background-color: rgb(39, 39, 42);
		}
		body, h2, p {
			margin: 0;
			padding: 0;
			font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, Segoe UI, Roboto, Helvetica Neue, Arial, Noto Sans, sans-serif, Apple Color Emoji, Segoe UI Emoji, Segoe UI Symbol, Noto Color Emoji;
		}

		.container {
			position: relative;
			text-align: left;
			color: #4f4f4f;
			width: 100vw;
			height: 100vh;
			display: flex;
			align-items: center;
			justify-content: center;
			flex-direction: column;
		}

		.container h2 {
			padding: 2rem;
			font-size: 2rem;
			color: rgb(244, 244, 245);
		}

		.container h2 small {
			font-size: .875rem;
			background-clip: text;
			background-image: linear-gradient(to right, rgb(236, 72, 153), rgb(168, 85, 247), rgb(59, 130, 246));
			color: transparent;
			text-transform: uppercase;
		}

		@media only screen and (min-width: 768px) {
			.container {
				flex-direction: row;
			}
			.container h2 {
				padding: 3rem;
				font-size: 3rem;
			}
		}
	</style>
</head>
<body>
	<div class="container">
		<h2 data-locale="Warsaw" data-offset="1">
			<p></p>
			<small>Warsaw, Poland</small>
		</h2>

		<h2 data-locale="Hanoi" data-offset="7">
			<p></p>
			<small>Hanoi, Vietnam</small>
		</h2>

		<h2 data-locale="Tokyo" data-offset="9">
			<p></p>
			<small>Tokyo, Japan</small>
		</h2>
	</div>

	<script>
		function searchClocks() {
			document.querySelectorAll(".container h2").forEach(item => {
				const timezone = {
					locale: item.getAttribute("data-locale"),
					offset: item.getAttribute("data-offset")
				};
				item.querySelector("p").innerHTML = calcTime(timezone);
				setInterval(() => {
					item.querySelector("p").innerHTML = calcTime(timezone);
				}, 1000);
			});
		}

		function calcTime(timezone) {
			const d = new Date(),
			utc = d.getTime() + (d.getTimezoneOffset() * 60000),
			nd = new Date(utc + (3600000 * timezone.offset));

			return nd.toLocaleDateString(undefined, {
				hourCycle: "h24",
				year: "numeric",
				month: "short",
				day: "numeric",
				weekday: "short",
				hour: "numeric",
				minute: "numeric"
			});
		}

		searchClocks();
	</script>
</body>
</html>
	<!DOCTYPE html>
	<html lang="en">
	<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<style>
	html, body {
	background-color: rgb(39, 39, 42);
	}
	body, h2, p {
	margin: 0;
	padding: 0;
	font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, Segoe UI, Roboto, Helvetica Neue, Arial, Noto Sans, sans-serif, Apple Color Emoji, Segoe UI Emoji, Segoe UI Symbol, Noto Color Emoji;
	}

	.container {
	position: relative;
	text-align: left;
	color: #4f4f4f;
	width: 100vw;
	height: 100vh;
	display: flex;
	align-items: center;
	justify-content: center;
	flex-direction: column;
	}

	.container h2 {
	padding: 2rem;
	font-size: 2rem;
	color: rgb(244, 244, 245);
	}

	.container h2 small {
	font-size: .875rem;
	background-clip: text;
	background-image: linear-gradient(to right, rgb(236, 72, 153), rgb(168, 85, 247), rgb(59, 130, 246));
	color: transparent;
	text-transform: uppercase;
	}

	@media only screen and (min-width: 768px) {
	.container {
	flex-direction: row;
	}
	.container h2 {
	padding: 3rem;
	font-size: 3rem;
	}
	}
	</style>
	</head>
	<body>
	<div class="container">
	<h2 data-locale="Warsaw" data-offset="1">
	<p></p>
	<small>Warsaw, Poland</small>
	</h2>

	<h2 data-locale="Hanoi" data-offset="7">
	<p></p>
	<small>Hanoi, Vietnam</small>
	</h2>

	<h2 data-locale="Tokyo" data-offset="9">
	<p></p>
	<small>Tokyo, Japan</small>
	</h2>
	</div>

	<script>
	function searchClocks() {
	document.querySelectorAll(".container h2").forEach(item => {
	const timezone = {
	locale: item.getAttribute("data-locale"),
	offset: item.getAttribute("data-offset")
	};
	item.querySelector("p").innerHTML = calcTime(timezone);
	setInterval(() => {
	item.querySelector("p").innerHTML = calcTime(timezone);
	}, 1000);
	});
	}

	function calcTime(timezone) {
	const d = new Date(),
	utc = d.getTime() + (d.getTimezoneOffset() * 60000),
	nd = new Date(utc + (3600000 * timezone.offset));

	return nd.toLocaleDateString(undefined, {
	hourCycle: "h24",
	year: "numeric",
	month: "short",
	day: "numeric",
	weekday: "short",
	hour: "numeric",
	minute: "numeric"
	});
	}

	searchClocks();
	</script>
	</body>
	</html>