function removejscssfile(filename, filetype){

    var targetelement=(filetype=="js")? "script" : (filetype=="css")? "link" : "none"; //determine element type to create nodelist from

    var targetattr=(filetype=="js")? "src" : (filetype=="css")? "href" : "none"; //determine corresponding attribute to test for

    var allsuspects=document.getElementsByTagName(targetelement);

    for (var i=allsuspects.length; i>=0; i--){ //search backwards within nodelist for matching elements to remove

      if (allsuspects[i] && allsuspects[i].getAttribute(targetattr)!=null && allsuspects[i].getAttribute(targetattr).indexOf(filename)!=-1){

          allsuspects[i].parentNode.removeChild(allsuspects[i]); //remove element by calling parentNode.removeChild()

      }

    }

}

removejscssfile("//maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css", "css") ;//remove all occurences "somestyle.css" on page