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HTML 

              
                <div id="kaleidoscope" class="kaleidoscope"></div>
!

CSS 

              
                // Use segmentCount to add styles for the required number of segments.
// Only 6 and 8 work for now because I can't be bothered to fix the image overlap
$segmentCount: 8;
$step: 360 / $segmentCount;
$bgColour: rgb(51, 82, 102);
$imageUrl: 'https://assets.codepen.io/1366040/kaleidoscope-flower.svg';
// Uncomment this for a different photo
// $imageUrl: 'https://picsum.photos/1000';
// $imageUrl: 'https://assets.codepen.io/1366040/5328478.jpg';
// $imageUrl: 'https://assets.codepen.io/1366040/waves.png';

html, body {
	height: 100vh;
	overflow: hidden;
}

// Make the animation take the whole available space
.kaleidoscope {
	width: 100vw;
	height: 100vh;
	overflow: hidden;
	background: $bgColour;

	// Place all segments in the bottom left quadrant of the screen
	&__segment {
		position: absolute;
		left: 0;
		top: 50%;
		height: 100vmax;
		width: 50%;
		z-index: 0;
		overflow: hidden;
		// Use the top right corner as the attachment point for when we're doing our rotations
		transform-origin: 100% 0;
		
		// Rotate each segment by an appropriate number of degrees so that they cover the whole space. 
		// Every one of them will have their initial top right corner in the middle of the screen
		@for $i from 1 through $segmentCount {
			&:nth-child(#{$i}) {
				transform: rotate(#{$step * $i}deg);
			}
		}
	}

	// Image is actually a div / wrapper inside the kaleidoscope__section element
	// We apply a background image to it and rotate it so that only a portion of it is visible
	&__image {
		position: relative;
		top: 0;
		left: 100%;
		height: 100%;
		width: 100%;
		background-image: url($imageUrl);
		background-position: center;
		transform-origin: 0 0;
		// scaleX(-1) will flip the image horizontally so we get the mirror-like reflection in each pair of sections
		transform: scaleX(-1) rotate(0deg);
		transition: background-position 1s;

		.kaleidoscope__segment:nth-child(2n) & {
			// Reverse the flip on images in every other section
			transform: rotate(#{360 / $segmentCount}deg);
		}
	}
	
}
!

JS 

              
                (function () {
	// Either 6 or 8 for now, please!
	const segmentCount = 8;
	const wrapper = document.querySelector('#kaleidoscope');
	let images = createSegments(segmentCount, wrapper);

	// Generate the segments and image wrappers with js
	// Could be done on the BE if that's your thing
	function createSegments(count, wrapper) {
		let images = [];

		for(let i = 0; i < count; i++) {
			const element = document.createElement('div');
			element.classList.add('kaleidoscope__segment');

			const image = document.createElement('div');
			image.classList.add('kaleidoscope__image');

			element.appendChild(image);
			images.push(image);
			wrapper.appendChild(element);
		}

		return images;
	}

	// Update background position on mouse move
	function handleMouseMove(e) {
		const nx = e.pageX;
		const ny = -e.pageY;

		images.forEach(image => {
			image.style.backgroundPosition = [nx + "px", ny + "px"].join(' ');
		});
	}

	// Do not do the animation for people who do not want it
	if(window.matchMedia("(prefers-reduced-motion: no-preference)")) {
		wrapper.addEventListener("mousemove", handleMouseMove);
	}
})();
!
999px

Console