1、把图片作为边框

border:10px solid transparent;border-image:url('./assets/images/login_bg.png') 30 round;

2、斜线边框
斜线边框可以给页面元素增加一份生动感。可以使用linear-gradient()函数来设置。

 .box{position:relative;border-top:4px solid #667db6;border-bottom:4px solid #5991ce;background:linear-gradient(45deg, #5991ce 49%, transparent 49%) 100% 0,linear-gradient(-45deg, #5991ce 49%, transparent 49%) 100% 100%;background-size:30px 30px;background-repeat:no-repeat;}