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HTML

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Insecure Resource

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <main>
	<div class="bounds">
		<div class="static">
			<p>This is a non-draggable element</p>
			<p>the boxes shouldn't be dragging over</p>
		</div>
		<div class="static">
			<p>This is another non-draggable</p>
			<p>element placed randomly</p>
		</div>
		<div class="box">box 1</div>
		<div class="box">box 2</div>
		<div class="box">box 3</div>
		<div class="box">box 4</div>
		<div class="box">box 5</div>
	</div>
</main>
!

CSS 

              
                main {
	position: relative;
	background-color: #CCD1D9;
	width: 100%;
	height: 100%;
	padding: 64px;
	display: flex;
	justify-content: center;
	align-items: center;
}

.bounds {
	background-color: #fff;
	width: 100%;
	max-width: 1000px;
	height: 600px;

	.static {
		position: absolute;
		background-color: #A0D468;
		padding: 12px;
		border-radius: 8px;
		z-index: 1;
		pointer-events: none;
		
		&.overlapping {
			background-color: #ED5565;
		}
	}

	.box {
		position: absolute;
		background-color: #E6E9ED;
		width: 200px;
		padding: 24px;
		border: 1px solid #CCD1D9;
		border-radius: 12px;
		text-align: center;
		z-index: 2;
	}
}
!

JS 

              
                /* just randomly placing the boxes for a more entertaining example */
document.querySelectorAll('.box').forEach(box => {
	gsap.set(box, {
		x: 'random(0, 800, 1)',
		y: 'random(0, 600, 1)'
	});
});

gsap.set(document.querySelectorAll('.static')[1], {
	x: 'random(200, 300, 1)',
	y: 'random(200, 400, 1)'
});

/* makind the boxes draggable */
Draggable.create('.box', {
	bounds: '.bounds',
	type: 'x,y',
	edgeResistance: .8,
	inertia: true,
	onDrag: overlapHandler,
	onDragEnd: overlapHandler,
	onThrowComplete: overlapHandler
});

/* this where we check if any of the boxes is touching a static */
function overlapHandler()
{
	document.querySelectorAll('.static').forEach(static => {
		let isOverlapping = false;
		document.querySelectorAll('.box').forEach(box => {
			if (Draggable.get(box).hitTest(static)) {
				isOverlapping = true;
			}
		});
		
		static.classList[isOverlapping ? 'add' : 'remove']('overlapping');
	});
}

overlapHandler();
!
999px

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