<section id="photo-gallery">
		<div class="gallery-item">
				<img src="https://picsum.photos/200/300?random=1">
		</div>
		<div class="gallery-item">
				<img src="https://picsum.photos/200/100?random=1">
		</div>
		<div class="gallery-item">
				<img src="https://picsum.photos/400/400?random=1">
		</div>
		<div class="gallery-item">
				<img src="https://picsum.photos/400/600?random=1">
			</div>
		<div class="gallery-item">
				<img src="https://picsum.photos/200/200?random=1">
			</div>
		<div class="gallery-item">
				<img src="https://picsum.photos/500/400?random=1">
			</div>
	</section>
#photo-gallery{
	column-count: 3;
	column-gap: 10px;
	width:600px; 
	margin:0 auto;
}
img{
	max-width: 100%;
	height: auto;
}

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External JavaScript

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