JAVASCRIPT
$(window).load(function() {
var objectA = $('.a');
var objectB = $('.b');
var objectC = $('.c');
var objectAOffsetTop = objectA.offset().top;
var objectBOffsetTop = objectB.offset().top;
$(window).scroll(function() {
var scroll = $(window).scrollTop();
if ((scroll >= objectAOffsetTop) && (scroll <= objectBOffsetTop)) {
objectC.addClass("active");
} else {
objectC.removeClass("active");
}
});
});
