Several commonly used methods for centering CSS boxes (summary)

The first one:

Using the CSS position property

<style type="text/css">
        .div1 {
            width: 100px;
            height: 100px;
            border: 1px solid #000000;
            position: relative;
        }

        .div2 {
            width: 40px;
            height: 40px;
            background-color: red;
            position: absolute;
            margin: auto;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
        }
    </style>

    <div class="div1">
        <div class="div2">
        </div>
    </div>

Effect picture:

Second type:

Use the new CSS3 attributes table-cell, vertical-align:middle;

<style type="text/css">
        .div1 {
            width: 100px;
            height: 100px;
            border: 1px solid #000000;
            display: table-cell;
            vertical-align: middle;
        }

        .div2 {
            width: 40px;
            height: 40px;
            background-color: red;
            margin: auto;
        }

    </style>

    <div class="div1">
        <div class="div2">
        </div>
    </div>

Effect:

The third type:

Layout using flexbox

<style type="text/css">
    .div1 {
        width: 100px;
        height: 100px;
        border: 1px solid #000000;
        display: flex;
        /*!*flex-direction: column;*!Optional*/
        justify-content: center;
        align-items: center;
    }

    .div2 {
        height: 40px;
        width: 40px;
        background-color: red;
    }
</style>
<div class="div1">
    <div class="div2">
    </div>
</div>

Effect:

The fourth type:

Using the transform attribute (disadvantage: need to support Html5)

<style type="text/css">
    .div1 {
        width: 100px;
        height: 100px;
        border: 1px solid #000000;
        position: relative;
    }

    .div2 {
        height: 40px;
        width: 40px;
        background-color: red;
        position: absolute;
        top: 50%;
        left: 50%;
        -ms-transform: translate(-50%, -50%);
        -moz-transform: translate(-50%, -50%);
        -o-transform: translate(-50%, -50%);
        transform: translate(-50%, -50%);
    }
</style>
<div class="div1">
    <div class="div2">
    </div>
</div>

Effect picture:

This concludes this article on several commonly used methods (summary) for centering a CSS box. For more information on centering a CSS box, please search 123WORDPRESS.COM’s previous articles or continue browsing the following related articles. I hope you will support 123WORDPRESS.COM in the future!

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