MediaWiki:Common.css

/* CSS placed here will be applied to all skins */
 
.collapseButton {          /* 'show'/'hide' buttons created dynamically */
    float: right;          /* by the CollapsibleTables javascript in    */
    font-weight: normal;   /* [[MediaWiki:Common.js]]are styled here    */
    text-align: right;     /* so they can be customised.                */
    width: auto;
}
.navbox .collapseButton {  /* In navboxes, the show/hide button balances */
    width: 6em;            /* the vde links from [[Template:Tnavbar]],   */
}                          /* so they need to be the same width.         */