html {
background: url("https://img4.goodfon.com/wallpaper/nbig/2/39/tokho-toukhou-devushka-fon-mech.jpg") no-repeat center center fixed;
-webkit-background-size: cover;
-moz-background-size: cover;
-o-background-size: cover;
background-size: cover;
}
.card {
opacity: 0.9;
}
.blurry {
backdrop-filter: blur(7px) !important;
}
pre code {
color: #fff;
background-color: #aaa;
border: 1px solid #999;
display: block;
padding: 5px;
overflow-x: auto;
white-space: pre-wrap;
white-space: -moz-pre-wrap;
white-space: -pre-wrap;
white-space: -o-pre-wrap;
word-wrap: break-word;
}