Hello,   I am using GSAP for animation, What I am going is when user scrolls the 300 from the top then .signup_header class will active with top:100 which is working in the desktop. Now I have to set top:50px in the mobile device then how can I set for it.? because in the mobile also it's talking 100px.   I mean can we change the animation or CSS for the mobile device?   $(window).bind('scroll', function () {         if ($(window).scrollTop() > 300) {