<div class="quadrado"></div>
body {
	display: flex;
	justify-content: center;
	align-items: center;
	height: 100vh;
}

.quadrado {
	background: red;
	width: 50px;
	height: 50px;
	animation: go-back 1s;
}

@keyframes go-back {
	from {
		transform: translateX(100px);
	}
	to {
		transform: translateX(0);
	}
} 


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