.background-st-left {
    background-position: left top;
    background-image: url('img/Ziegelsteine-links.png');
}

.background-st-rechts {
    background-image: url('img/Ziegelsteine.png');
    background-position: right top;
    background-attachment: fixed;
    background-repeat: repeat-y;
}

.bg-opacity-90 {
}