function removeClasses(el, classes){
    var elClasses;
    if (useClassList && el.classList) {
        el.classList.remove(classes);
        return el.className;
    }
    classes = [].concat(classes||[]).join(' ').split(/\s+/);
    // return element classes that are NOT in the 'classes' array
    elClasses = (el.className||'').split(/\s+/).filter(function(cls){
        return classes.indexOf(cls) === -1;
    });
    // set the new className and return the string
    return el.className = elClasses.join(' ');
}
// remove className(s) from an element
remove className(s) from an element
remove className ( s ) from an element
function removeClasses(el, classes){
    var elClasses;
    if (useClassList && el.classList) {
        el.classList.remove(classes);
        return el.className;
    }
    classes = [].concat(classes||[]).join(' ').split(/\s+/);
    elClasses = (el.className||'').split(/\s+/).filter(function(cls){
        return classes.indexOf(cls) === -1;
    });
    return el.className = elClasses.join(' ');
}
function removeClasses ( el , classes ) { var elClasses ; if ( useClassList && el . classList ) { el . classList . remove ( classes ) ; return el . className ; } classes = [ ] . concat ( classes || [ ] ) . join ( ' ' ) . split ( / \s+ / ) ; elClasses = ( el . className || '' ) . split ( / \s+ / ) . filter ( function ( cls ) { return classes . indexOf ( cls ) === - 1 ; } ) ; return el . className = elClasses . join ( ' ' ) ; }
remove className(s) from an element
remove className ( s ) from an element
// return element classes that are NOT in the 'classes' array // set the new className and return the string