body{
    /* 透视 */
    perspective: 800px;
}
div{
    transform-style:preserve-3d;
    width:259px;
    height:396px;
    margin: 100px auto;
    position: relative;
}
div img{
    position: absolute;
    width:259px;
    height:396px;
    left:0;
    top:0;
    transition: all linear 2s;
    z-index: 0;
}
div img:nth-child(1){
    /* 这张图片背向我们的时候能否看到 */
    backface-visibility:hidden;
    z-index: 1;
}
div:active img{
    transform:rotateY(180deg)
}

    <div id="box">
        <img src="./pkOne.jpg" alt="">
        <img src="./pkTwo.jpg" alt="">
    </div>