CSS鼠标悬停图片加边框效果，页面布局发生错位的解决办法

.recomend-list{    width:1200px;    a{        @extend %fl;        margin-right: 30px;        width: 260px;        height: 440px;        border: 2px solid transparent;        @extend %borderbox;        &:hover{            border-color: #109ef3;        }    }    img{        width: 100%;        height: 100%;    }}