<!--
Source - https://stackoverflow.com/a
Posted by Alexey Ivanov
Retrieved 2025-12-23, License - CC BY-SA 3.0
-->

.container {  position: relative; }

.container:before {
    content: "";
    position: absolute;
    top: 0; 
    bottom: 0; 
    left: 0; 
    right: 0;
    z-index: 1;
    background-image: url('39C3/39C3-Visual-Power-Cycles-Repetition-RGB_electric-violet.png');
    opacity: 0.1;
}

.content {
    position: relative; 
    z-index: 2;
}