body::before, .header{
    background-image: url('/static/img/background.jpg');
    background-size: cover;
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
}

.header .mdl-navigation__link{
    color: #fff!important;
}

.header .material-icons {
    color: #eee!important;
}

.card-content {
    opacity: .85;
}

.card{
    background-color: #2a2a2a;;
    color:#eee !important;
}
article p span{
    color:#eee !important;
}
.date a {
    color:#eee;
}
pre, pre code{
    background: #aaa;
}
.card ul{
    background-color: #2a2a2a !important;
}
body::before, .header{
    background-image: url('/static/img/background.jpg');
    background-size: cover;
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
}

.header .mdl-navigation__link{
    color: #fff!important;
}

.header .material-icons {
    color: #eee!important;
}

.card-content {
    opacity: .85;
}

.card{
    background-color: #2a2a2a;;
    color:#eee !important;
}
article p span{
    color:#eee !important;
}
.date a {
    color:#eee;
}

.card ul{
    background-color: #2a2a2a !important;
}
Change stardust theme pre background-color
Change stardust theme pre background-color
