css图片根据父元素大小改变大小

<a class="position-relative heightAuto" href="javascrpt:;">
  <img class="objectfit-scale" src="./images/302143215.jpg" alt="">
</a>
<style>
    .position-relative{
        position: relative;
        width:500px;
        height:500px;   //可自定义
    }
    .objectfit-scale{
    height: 100%;
	width: auto;
	left:50%;
	position: absolute;
	-webkit-transform: translateX(-50%);
	-ms-transform: translateX(-50%);
	-moz-transform: translateX(-50%);
    object-fit: scale-down;
}
</style>