css 网格线

白色网格线

background: #58a;
    background-image:
        linear-gradient(rgba(255,255,255,.3) 1px, transparent 0),
        linear-gradient(90deg, rgba(255,255,255,.3) 1px, transparent 0),
        linear-gradient(white 1px, transparent 0),
        linear-gradient(90deg, white 1px, transparent 0);
    background-size: 15px 15px, 15px 15px, 75px 75px, 75px 75px;

黑色网格线

background-image: linear-gradient(90deg, rgba(50, 0, 0, 0.05) 3%, rgba(0, 0, 0, 0) 3%), linear-gradient(360deg,rgba(50, 0, 0, 0.05) 3%, rgba(0, 0, 0, 0) 3%);
    // background-size: 20px 20px;
     background-position: center center;