Swiper Last slide space 

adding slidePerView and SpaceBetween will solve it – slidesPerView: “1.5”

http://sumnima-clear.mybigcommerce.com/

var swiper = new Swiper(".swiper", {
    slidesPerView: 4,
    spaceBetween: 16,
    breakpoints: {
        320: {
            watchSlidesProgress: true,
            slidesPerView: "1.5",
            shortSwipes: false
        },
        500: {
            watchSlidesProgress: true,
            slidesPerView: "2",
            shortSwipes: false
        },
        1024: {
            preventInteractionOnTransition: true,
            watchSlidesProgress: true,
            slidesPerView: "4.5",
            shortSwipes: false
        },
    },
});