User:Volker Siegel/modern.css

    /* This moves the sidebar off-screen */ 
    #mw-panel { 
        opacity: 0; 
        margin-left: -11em; 
    } 
    /* This moves other stuff into the leftover space */ 
    #content, #head-base, #footer, #mw-head-base { 
        margin-left: -1px; 
    } 
    /* Nicer presentation for the left-hand tabs */ 
    #left-navigation { 
        margin-left: 1em; 
    }