SOURCE

 <div class="img-box">
    <img src="https://www.keaidian.com/uploads/allimg/190424/24110307_4.jpg" class="img">
 </div>

.img-box{
    width: 390px;
    height: 296px;
    overflow: hidden;  
}
.img{
    display: block;
    width: 100%;
    height: 100%;
    transition: all 1s;
}
.img:hover{
    transform: scale(1.4); //放大 倍数随意
}