View some examples of work I've done for other clients.
// Show filtered elements function w3AddClass(element, name) { var i, arr1, arr2; arr1 = element.className.split(" "); arr2 = name.split(" "); for (i = 0; i < arr2.length; i++) { if (arr1.indexOf(arr2[i]) == -1) { element.className += " " + arr2[i]; } } } // Hide elements that are not selected function w3RemoveClass(element, name) { var i, arr1, arr2; arr1 = element.className.split(" "); arr2 = name.split(" "); for (i = 0; i < arr2.length; i++) { while (arr1.indexOf(arr2[i]) > -1) { arr1.splice(arr1.indexOf(arr2[i]), 1); } } element.className = arr1.join(" "); }