CSS代码

body::before {
            background-image: linear-gradient(90deg, rgba(60, 10, 30, .04) 3%, transparent 0), linear-gradient(1turn, rgba(60, 10, 30, .04) 3%, transparent 0);
            background-size: 20px 20px;
            background-position: 50%;
            background-repeat: repeat;
}