let items=document.querySelectorAll('.carousel .carousel-item')
items.forEach((el)=>{const minPerSlide=4
let next=el.nextElementSibling
for(var i=1;i<minPerSlide;i++){if(!next){next=items[0]}
let cloneChild=next.cloneNode(true)
el.appendChild(cloneChild.children[0])
next=next.nextElementSibling}})