图片水平垂直居中

HTML

<div class="box">
    <img src="http://www.sogou.com/images/logo/new/sogou.png" alt=""/>
</div>

CSS

* {
    margin: 0;
    padding: 0;
}

.box {
    height: 100vh;
    width: 100%;
    background-color: #919191;
}

img {
    width: 100%;
    height: 100%;
    display: block;
    object-fit: none;
    /*
    object-fit: contain;
    object-fit: cover;
    */
    /* object-position: 10px 10px; */
}