复杂的背景图案

网格

body{
            background: white;
            background-image: linear-gradient(90deg,rgba(200,0,0,.5) 50%,transparent 0),
                              linear-gradient(rgba(200,0,0,.5) 50%,transparent 0);
            background-size: 30px 30px;
        }

桌布方格纹

不管网格多大，线条始终是1px:

body{
            background: #58a;
            background-image: linear-gradient(white 1px, transparent 0),
                              linear-gradient(90deg,white 1px, transparent 0);
            background-size: 30px 30px;
        }

蓝图网格

 body{
            background: #58a;
            background-image: 
                linear-gradient(white 2px, transparent 0),
                linear-gradient(90deg,white 2px, transparent 0),
                linear-gradient(hsla(0,0%,100%,.3) 1px, transparent 0),
                linear-gradient(90deg,hsla(0,0%,100%,.3) 1px, transparent 0);
            background-size: 75px 75px, 75px 75px,
                             15px 15px, 15px 15px;
        }

更逼真的蓝图网格
波点

        body{
            background: #655;
            background-image: radial-gradient(tan 30%,transparent 0),radial-gradient(tan 30%,transparent 0);
            background-size: 30px 30px;
            background-position: 0 0,15px 15px;
        }

使用偏移定位的波点 sass预处理器代码
棋盘

 body{
            background: #eee;
            background-image: linear-gradient(45deg,#bbb 25%,transparent 0),
                              linear-gradient(45deg,transparent 75%,#bbb 0),
                              linear-gradient(45deg,#bbb 25%,transparent 0),
                              linear-gradient(45deg,transparent 75%,#bbb 0);
            background-size: 30px 30px;
            background-position: 0 0,15px 15px,15px 15px,30px 30px;
        }

用两个直角三角形拼接再偏移