#home   {
        width: 65%
        min-width: 950px;
        background-color: #fff;
        padding: 30px;
        margin-top: 20px;
        margin-bottom: 20px;
        box-shadow: 0 2px 6px rgba(100, 100, 100, 0.3);
}
body {
margin: 0 auto;
opacity: 0.8;
width: 65%;
min-width: 1080px;
background-color: #fff;
padding: 30px;
margin-top: 50px;
margin-bottom: 50px;
box-shadow: 0 2px 6px rgba(100, 100, 100, 0.3);
}
body {
    color: #000;
    background: url(https://s2.ax1x.com/2019/09/10/na9CLV.png) fixed;
        background-repeat: repeat;
        background-size: auto;
    background-size: cover;
    background-repeat: repeat;
    font-size: 12px;
    min-height: 101%;
}


fieldset, img {
    border: 0;
        border-top-color: currentcolor;
        border-top-style: none;
        border-top-width: 0px;
        border-right-color: currentcolor;
        border-right-style: none;
        border-right-width: 0px;
        border-bottom-color: currentcolor;
        border-bottom-style: none;
        border-bottom-width: 0px;
        border-left-color: currentcolor;
        border-left-style: none;
        border-left-width: 0px;
        border-image-outset: 0;
        border-image-repeat: stretch;
        border-image-slice: 100%;
        border-image-source: none;
        border-image-width: 1;
}

{
    margin: 0;
        margin-top: 0px;
        margin-right: 0px;
        margin-bottom: 0px;
        margin-left: 0px;
    padding: 0;
        padding-top: 0px;
        padding-right: 0px;
        padding-bottom: 0px;
        padding-left: 0px;
}

<canvasid="c_n9"width="1920"height="990"style="position: fixed; top: 0px; left: 0px; z-index: -1; opacity: 0.5;"></canvas>

<script src="https://files.cnblogs.com/files/siwuxie095/canvas-nest.min.js"></script>