body {
    margin: 0;
    padding: 0;
    /* background-color: #000; */
}

.cont {
    position: relative;
    /* width: 100%;
    height: 800px;*/
    z-index: 0;
}

.block {
    position: relative;
    /* margin: 300px auto 0; */
    width: 500px;
    height: 250px;
    background: linear-gradient(0deg, #b47e34, #ddc599);
    border-radius: 10px;
    margin: 10px;
}

.block:before,
.block:after {
    content: '';
    position: absolute;
    left: -2px;
    top: -2px;
    background: linear-gradient(45deg, #fb0094, #0000ff, #00ff00, #ffff00, #ff0000, #fb0094, #0000ff, #00ff00, #ffff00, #ff0000);
    /* background: linear-gradient(45deg, #b47e34, #1f4128, #ddc599, white, #b47e34, blue, red, yellow, gray); */
    /* background: linear-gradient(45deg, #FFFFFF, #FFFFCC, #FFFF99, #FFFF66, #FFFF33, #FFFF00, #FFCCFF, #FFCCCC, #FFCC99, #FFCC66, #FFCC33, #FFCC00, #FF99FF, #FF99CC, #FF9999, #FF9966, #FF9933, #FF9900, #FF66FF, #FF66CC, #FF6699, #FF6666, #FF6633, #FF6600, #FF33FF, #FF33CC, #FF3399, #FF3366, #FF3333, #FF3300, #FF00FF, #FF00CC, #FF0099, #FF0066, #FF0033, #FF0000, #CCFFFF, #CCFFCC, #CCFF99, #CCFF66, #CCFF33, #CCFF00, #CCCCFF, #CCCCCC, #CCCC99, #CCCC66, #CCCC33, #CCCC00, #CC99FF, #CC99CC, #CC9999, #CC9966, #CC9933, #CC9900, #CC66FF, #CC66CC, #CC6699, #CC6666, #CC6633, #CC6600, #CC33FF, #CC33CC, #CC3399, #CC3366, #CC3333, #CC3300, #CC00FF, #CC00CC, #CC0099, #CC0066, #CC0033, #CC0000, #99FFFF, #99FFCC, #99FF99, #99FF66, #99FF33, #99FF00, #99CCFF, #99CCCC, #99CC99, #99CC66, #99CC33, #99CC00, #9999FF, #9999CC, #999999, #999966, #999933, #999900, #9966FF, #9966CC, #996699, #996666, #996633, #996600, #9933FF, #9933CC, #993399, #993366, #993333, #993300, #9900FF, #9900CC, #990099, #990066, #990033, #990000, #66FFFF, #66FFCC, #66FF99, #66FF66, #66FF33, #66FF00, #66CCFF, #66CCCC, #66CC99, #66CC66, #66CC33, #66CC00, #6699FF, #6699CC, #669999, #669966, #669933, #669900, #6666FF, #6666CC, #666699, #666666, #666633, #666600, #6633FF, #6633CC, #663399, #663366, #663333, #663300, #6600FF, #6600CC, #660099, #660066, #660033, #660000, #33FFFF, #33FFCC, #33FF99, #33FF66, #33FF33, #33FF00, #33CCFF, #33CCCC, #33CC99, #33CC66, #33CC33, #33CC00, #3399FF, #3399CC, #339999, #339966, #339933, #339900, #3366FF, #3366CC, #336699, #336666, #336633, #336600, #3333FF, #3333CC, #333399, #333366, #333333, #333300, #3300FF, #3300CC, #330099, #330066, #330033, #330000, #00FFFF, #00FFCC, #00FF99, #00FF66, #00FF33, #00FF00, #00CCFF, #00CCCC, #00CC99, #00CC66, #00CC33, #00CC00, #0099FF, #0099CC, #009999, #009966, #009933, #009900, #0066FF, #0066CC, #006699, #006666, #006633, #006600, #0033FF, #0033CC, #003399, #003366, #003333, #003300, #0000FF, #0000CC, #000099, #000066, #000033, #000000); */
    /* background: linear-gradient(45deg, black, white, maroon, white, #b47e34, white); */
    /* background: linear-gradient(45deg, white, gray, white, #b47e34); */
    background-size: 400%;
    width: calc(100% + 4px);
    height: calc(100% + 4px);
    z-index: -1;
    animation: steam 20s linear infinite;
    border-radius: 10px;
}

@keyframes steam {
    0% {
        background-position: 0 0;
    }
    50% {
        background-position: 400% 0;
    }
    100% {
        background-position: 0 0;
    }
}

.block:after {
    filter: blur(50px);
}