If at the time of designing my page I find that to use an external javascript library, such as a carousel image gallery, it needs to implement a CSS stylesheet, but these styles make other aspects change of the page, how can I easily limit all that sheet to a single div, without modifying each and every one of the selectors on the page? I ask this because I happened to have two external libraries, each one needed to link a CSS sheet of its own, but these were stepped on each other, thus generating a malfunction of the plugins.