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HTML 

              
                <!-- This uses the old checkbox-and-siblings trick, by using the CSS :checked property, check the CSS below. The order of these HTML elements is therefore important -->

<input id="btn" type="checkbox"><!-- will be hidden -->
<label for="btn"></label><!-- toggle, will activate checkbox -->
<div class="plate"></div><!-- animating background -->



















<a target="_blank" href="https://codepen.io/josfabre/pens/public" style="position: fixed; left: 2em; top: 2em; font-family: Sans-Serif; color: #fcfcfc; font-size: 13px; text-decoration: none; text-transform: uppercase; padding: 0.5em 1em; border: 1px solid #fcfcfc; border-radius: 6px; opacity: 0.9; ">All my pens</a>

<section style="position: fixed; left: 2em; bottom: 2em; font-family: 'Telefon', Sans-Serif; color:grey;">
  <h3>Other pens</h3>
  <ul style="display:flex;list-style-type:none;margin: 0; padding: 0;">
  <li style="margin-right: 1em;"><a href="https://codepen.io/josfabre/pen/abReBvP" target="_blank" style="color:grey;text-decoration:none;font-size:0.8rem;"><img style="border-radius: 8px;height: 100px; width: auto;box-shadow: 0 0 10px grey;" src="https://assets.codepen.io/439000/Screenshot+2023-06-07+at+08.39.48.png"><br>Real Slots Reels - Slot Machine</a></li>
  <li style="margin-right: 1em;"><a href="https://codepen.io/josfabre/pen/jOegyyJ" target="_blank" style="color:grey;text-decoration:none;font-size:0.8rem;"><img style="border-radius: 8px;height: 100px; width: auto;box-shadow: 0 0 10px grey;" src="https://assets.codepen.io/439000/Screenshot+2023-06-07+at+08.56.26.png"><br>Magnifying Glass Newspaper</a></li>
</section>
!

CSS 

              
                body {
	height: 100vh;
	background-image: linear-gradient(45deg, #555 10%, #888 90%);
	display: flex;
	justify-content: center;
	align-items: center;
  overflow: hidden;
}

.plate {
	position: fixed;
	left: 50%;
	top: 50%;
	width: 100vw;
	height: 0;
	padding-bottom: 100%;
	border-radius: 50%;
	transform: translate(-50%, -50%) rotate(0) scale(2);
	z-index: -1;
	background-image: repeating-conic-gradient(
		from 45deg at 50% 50%,
		#4a4 0deg 10deg,
		#5b5 10deg 20deg,
		#6c6 20deg 30deg
	);
	visibility: hidden;
	opacity: 0;
}

@keyframes rot {
	to {
		transform: translate(-50%, -50%) rotate(360deg) scale(2);
	}
}

input[type="checkbox"] {
	display: none;

  /* toggle in the OFF state */
	~ label {
		position: relative;
		display: block;
		width: 140px;
		height: 72px;
		border-radius: 40px;
		border: 4px solid #999;
		transition: transform 200ms cubic-bezier(0.41, -0.01, 0.63, 1.09);
		cursor: pointer;
		background: rgba(black, 0.3);

		&::before,
		&::after {
			position: absolute;
			top: 2px;
			left: 2px;
			width: 68px;
			height: 68px;
			border-radius: 36px;
			content: "";
			transition: all 220ms cubic-bezier(0.76, 0.01, 0.15, 0.97);
		}

		&::before {
			background-image: linear-gradient(45deg, #383 10%, #4b4 90%);
		}

		&::after {
			background-color: #999;
		}
	}

	/* toggle in the ON state */
	&:checked ~ label {
		border: 4px solid #fff;
		transform: scale(1.01);
		box-shadow: 0 0 120px 10px #9f9;
		border-color: #afa;
		background: rgba(green, 0.6);

		&::before {
			width: 136px;
		}

		&::after {
			transform: translateX(68px);
			background-color: #4c4;
			box-shadow: -4px 0 4px rgba(black, 0.1);
		}
	}

  /* This is the part that activates the background when the checkbox is checked */
	&:checked ~ div {
		// background: yellow;
		opacity: 1;
		visibility: visible;
		transition: opacity 240ms, visibility 0s;
		animation: rot 10s linear infinite;
	}
}
!

JS
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999px

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