CSS vertical horizontal center, css vertical center

CSS vertical horizontal center, css vertical center

To sum up, text-align: center is used for horizontal center of elements in the row, margin-left: auto is used for horizontal center of block-level elements, and margin-right: auto is used for horizontal center;

 

First, we will discuss the situation of a single row.

There is no doubt that this is the simplest case.

The HTML structure is as follows:

1 <div class="demo">2     <span>111111111111111111111111111111111111</span>3 </div>

The height is not fixed (this method is also applicable when multiple texts are written and will not be discussed below)

1 .demo {2     text-align: center; 3     padding-top: 20px;4     padding-bottom: 20px;5 }

Fixed height

1 .demo {2     text-align: center;3     height: 100px;4     line-height: 100px;5 }

 

Next, we will discuss the situation of multiple rows.

The HTML structure is as follows:

1 <div class="demo">2     <span>111111111111111111111111111111111111<br />22222222222222222222</span>3 </div>

When the height is not fixed, you only need to add the pading value.

Fixed height

Method 1: Set "display: table" for the parent element and "display: table-cell" for the child element. The table feature is used.

 1 .demo { 2     height: 100px; 3     display: table; 4     margin-left: auto; 5     margin-right: auto; 6 } 7 .demo span { 8     display: table-cell; 9     vertical-align: middle;10 }

Method 2: Set position: relative for the parent element and position: absolute for the child element. It mainly utilizes the characteristics of the Center of translate relative to the element itself.

 1 .demo { 2   position: relative; 3   height: 100px; 4 } 5  6 .demo span { 7   position: absolute; 8   left: 50%; 9   top: 50%;10   -webkit-transform: translate(-50%, -50%);11       -ms-transform: translate(-50%, -50%);12           transform: translate(-50%, -50%);13 }

Method 3: Use flex layout.

.demo {  height: 100px;  display: -webkit-box;  display: -webkit-flex;  display: -ms-flexbox;  display: flex;  -webkit-box-pack: center;  -webkit-justify-content: center;      -ms-flex-pack: center;          justify-content: center;  -webkit-box-align: center;  -webkit-align-items: center;      -ms-flex-align: center;          align-items: center;}

Method 4: vertical center is implemented using the following: after,: before pseudo class, And the inline-block feature.

 1 .demo { 2   height: 100px; 3   text-align: center; 4 } 5  6 .demo:after, .demo:before { 7   display: inline-block; 8   vertical-align: middle; 9   width: 0;10   height: 100%;11   visibility: hidden;12   content: '';13 }14 15 .demo span {16   display: inline-block;17   vertical-align: middle;18 }

 

Now I think of this.