- absolute加margin方案
div{ position: absolute; width: 100px; height: 100px; left: 50%; top: 50%: margin-top: -50px; margin-left: -50px; }
- fixed 加 margin 方案
div{ position: fixed; width: 100px; height: 100px; top: 0; right:0; left: 0; bottom: 0; margin: auto; }
- display:table 方案
div{ display: table-cell; vertical-align: middle; text-align: center; width: 100px; height: 100px; }
- 行内元素line-height方案
div{ text-align: center; line-height: 100px; }
- flex 弹性布局方案
div{ display: flex; align-items: center; justify-content:center }
- transform 未知元素宽高解决方案
div{ position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%) }