#bg-css {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background-color: #ffffff;
    opacity: 0.1;
    background-size: 7px 7px;
    background-image: repeating-linear-gradient(45deg, #f74545 0, #f74545 0.7000000000000001px, #ffffff 0, #ffffff 50%);
}