DNS - 旭氏美术馆

css3垂直居中4种方式

未知元素宽度

#target{
  position:absolute;
  left:50%;
  top:50%;
  transform:translate(-50%,-50%)
}

flex

#container{
  display:flex;
  justify-content:center;
  align-items:center;
}

table

body{
  display:table;
}
#container{
  display:table-cell;
  vertical-align:middle;
}
#target{ 
  display:inline-block;
}

元素已知宽度 ``` #target{ width:20px; height:20px; background-color:yellow; position:absolute; left:50%; top:50%; margin: -10px 0 0 -10px

} ```

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