var scrollTopBtn=document.querySelector('#scroll');window.onscroll=function(){scrollFunction()};function scrollFunction(){if(document.body.scrollTop>0||document.documentElement.scrollTop>0){scrollTopBtn.style.display="block";}else{scrollTopBtn.style.display="none";}}
scrollTopBtn.addEventListener('click',function(){window.scroll({top:0,left:0,behavior:'smooth'});});