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Babel includes JSX processing.

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Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.


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If enabled, your code will be formatted when you actively save your Pen. Note: your code becomes un-folded during formatting.

Editor Settings

Code Indentation

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	<input id=un type=checkbox> <label for=un>un</label>
	<input id=deux type=checkbox checked> <label for=deux>deux</label>
	<input id=trois type=checkbox> <label for=trois>trois</label>
	<input id=quatre type=checkbox> <label for=quatre>quatre</label>


	display: grid;
	width: 100px; height: 70px;
	line-height: 60px;
	text-align: center;
	cursor: pointer;
	border: 0; 
	appearance: none; -webkit-appearance: none;

	grid-area: 1/1;
	border-radius: 40px;
	mix-blend-mode: hard-light;
	pointer-events: none;

	transform: translate(10px, 10px);
	background: green;
	text-indent: -20px;
	font-size: 25px;
	content: '✓';
	color: white;

	background: blue;
	font-size: 50px;
	content: '⨯';

	mix-blend-mode: unset;
	color: transparent;

	display: grid;
	grid:  repeat(4, 100px) / 150px 1fr;
	align-items: center;
	width: max-content;

	font: 60px Girassol;
	color: lime;
	text-shadow: 2px 2px 0 blue;
	cursor: pointer;

	display: grid;
	height: 100vh;
	align-items: center; 
	justify-items: center;
	background: white;
	user-select: none; -webkit-user-select:  none;
	-webkit-tap-highlight-color: transparent;


This code is for heuristic purposes only. Other ways you can play this are by trying different blend mode values, or using a single element with two backgrounds that are blended with `background-blend-mode`. You can also not blend the elements at first and do it after the box is checked. Hide the pseudo-elements or replace them with normal elements that can be hidden if they don't work as expected in other UAs or medias.