html
<div class="content">
<div>我是內(nèi)容</div>
</div>
第一種
.content
width: 300px;
height: 300px;
position: relative;
border: 1px solid #ccc;
div
display:inline-block;
position: absolute;
left: 50%;
top: 50%;
transform: translate(-50%,-50%);
background-color: red;
image.png
第二種
.content
width: 300px;
height: 300px;
border: 1px solid #ccc;
display: table-cell;
text-align: center;
vertical-align: middle;
div
display:inline;
background-color: red;
image.png
第三種
.content
width: 300px;
height: 300px;
border: 1px solid #ccc;
display: flex;
justify-content: center;
align-items: center;
div
background-color: red;
image.png
