HTML 代码

<div class="box">
	<div class="card">正面</div>
	<div class="card back">背面</div>
</div>

CSS 代码

* {
	margin: 0;
	padding: 0;
}
.box {
	position: relative;
	width: 300px;
	height: 320px;
	transition: 2s;
	transform-style: preserve-3d;
}
.box:hover {
	transform: rotateY(180deg);
}
.card {
	position: absolute;
	top: 0;
	left: 0;
	width: 100%;
	height: 320px;
	backface-visibility: hidden;
	background-color: #ff6600;
}
.card.back {
	transform: rotateY(180deg);
	background-color: #ff2200;
}

效果如下：