···设置两个盒子
<div class="parent"> <div class="child"> </div></div>
方法一:absolute
<!-- //父元素相对定位,子元素绝对定位 -->
<!-- //绝对定位盒子模型有个特点:left + right + width + padding + margin = 包含块的宽度;此时可以将left、right设置为0;padding、margin未设置是默认为0;所以将margin设置为auto,使得元素自动居中; -->
<style type="text/css"> *{ margin: 0; padding: 0; } .parent{ position: relative; width: 200px; height: 200px; border: 1px solid black; } .child{ position: absolute; left: 0; right: 0; top: 0; bottom: 0; margin: auto; width: 100px; height: 100px; background: pink; } </style>
方法二:absolute + 负margin
.parent{ position: relative; width: 200px; height: 200px; border: 1px solid black; } .child{ position: absolute; left: 50%; top: 50%; margin-left: -50px; margin-top: -50px; width: 100px; height: 100px; background: pink; } 方法三:flex布局 //只需设置父节点属性,无需设置子元素 // 父元素设置 display: flex; justify-content:center; align-items:Center;
转载于:https://www.cnblogs.com/veraNotes/p/10885636.html
