SOURCE

<div class="flipper">
	<span class="flipper-object flipper-vertical">
		<span class="panel front">the front</span>
		<span class="panel back">the back</span>
	</span>
</div>

.flipper {
	position: relative;
	width: 300px;
	height: 44px;
	perspective: 300px;
}
.flipper-object {
	position:absolute;
	transition: transform 1s;
	width: 100%;
	height: 100%;
	transform-style: preserve-3d;
}
.panel {
	border: 1px solid black;
	position: absolute;
	backface-visibility: hidden;
	width: 100%;
	height: 100%;
	display: flex;
	align-items: center;
	justify-content: center;
}
.flipper-vertical .back {
	transform: rotateX(180deg);
	/* background-color: tomato; */
}
.flipper-object .front {
	/* background-color: #739328; */
}

.flipper:hover .flipper-vertical {
	transform: rotateX(180deg);
}