آموزش ساخت اسلایدر دست‌نویس : صفر تا صد HTML ,CSS ,JS

.slider-container{
    padding: 40px;
    max-width: 1300px;
    margin: 0 auto;
    position: relative;
}.slider{
    width: 100%;
    overflow: hidden;
    display: flex;
    scroll-behavior: smooth;
    gap: 8px;
}.items{
    min-width: 100%;
    max-width: 100%;
}.item{
    min-width: 100%;
    max-width: 100%;
    height: 300px;
    object-fit: cover;
}.nav-buttons{
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    font-size: 24px;
    background: #1C1C1C; 
    color: white;
    width: 35px;
    height: 35px;
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 50%;
    cursor: pointer;
}#left{
    left: 0px;
}#right{
    right: 0px;
}
@media screen and (min-width:724px) {
   .items{
      min-width: 50%;
      max-width: 50%;
    }
}
@media screen and (min-width:1024px) {
   .items{
        min-width: 33.333%;
        max-width: 33.333%;
    }
}

const width = window.innerWidth 
const counts = width < 724 ? 1 : width < 1024 ? 2 : 3; 

const next = document.getElementById("right"); 
const prev = document.getElementById("left"); 
const slider = document.querySelector(".slider"); 
const items = document.querySelectorAll(".items"); 

let scrollNavigation = 0; 
const sliderGap = 8 ; // .slider{gap:8px} 
const scrollValue = items[0].offsetWidth + sliderGap;  

const goNext = () =>{ 
    if (scrollNavigation < items.length - counts) { 
            scrollNavigation += 1; 
    } else { 
            scrollNavigation = 0; 
    }
    slider.scrollLeft = scrollValue * scrollNavigation; 
}; 
const goPrev = () =>{ 
    if (scrollNavigation > 0) { 
            scrollNavigation -= 1; 
    } else { 
            scrollNavigation = items.length - counts; 
    } 
    slider.scrollLeft = scrollValue * scrollNavigation; 
}; 

next.addEventListener("click", goNext); 
prev.addEventListener("click", goPrev); 

setInterval(()=>{ 
        goNext(); 
},5000)