圆角

        div{width: 100px;height: 100px;background-color: saddlebrown;border-radius: 5px;}

阴影

        div{width: 200px;height: 100px;background-color: saddlebrown;margin: 0 auto;box-shadow: 10px 10px 20px rgba(0, 0, 0, 0.5);}