m0_46360310的博客

.parent { background-color: gray; height: 500px; width: 500px; position: relative;}.child { background-color: greenyellow; height: 100px; width: 100px; position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%);}.parent { ba

问题 <div class="box"> <div class="leftbox"></div> <div class="rightbox"></div> </div>如果给leftbox和rightbox添加上宽高与浮动的话，box盒子无法被撑开。在尾部添加一个没有尺寸的空元素 <div class="box"> <div class="leftbox"></div>

HTML部分代码<div class="wrap"> <ul class="list"> <li class="item active">0</li> <li class="item">1</li> <li class="item">2</li> <li class="item">3</li> <li class="item">4</l