var $html = $("html");
if ($html.hasClass('m320') || $html.hasClass('m768')) {
// do stuff
// https://stackoverflow.com/questions/10559153/jquery-hasclass-for-multiple-values-in-an-if-statement
}
jQuery('button').click(function(){
var hcls =jQuery('p').hasClass('class2').addClass('class2');
if(hcls == true){
alert('Yuor class is remove ');
}
else{
alert('your class is nnot remove');
}
});