JAVASCRIPT

jquery select multiple elements with same class

function checkads() {
    $('.someclass').each(function(){           
       if($(this).height() < 50) {
             $(this).parent().parent().prepend('<div id="ad-notice">Please support our website</div>');
       }
   });
}

$(document).ready(checkads);

jquery select 2 classes

$(".class1, .class2, .class3") //select classes independently