<div class="mask">
  <div class="swiper-container">
    <div class="swiper-wrapper">
      <div class="swiper-slide">Slide 1</div>
      <div class="swiper-slide">Slide 2</div>
      <div class="swiper-slide">Slide 3</div>
      <div class="swiper-slide">Slide 4</div>
      <div class="swiper-slide">Slide 5</div>
      <div class="swiper-slide">Slide 6</div>
      <div class="swiper-slide">Slide 7</div>
      <div class="swiper-slide">Slide 8</div>
      <div class="swiper-slide">Slide 9</div>
      <div class="swiper-slide">Slide 10</div>
      <div class="swiper-slide">Slide 11</div>
      <div class="swiper-slide">Slide 12</div>
      <div class="swiper-slide">Slide 13</div>
      <div class="swiper-slide">Slide 14</div>
      <div class="swiper-slide">Slide 15</div>
      <div class="swiper-slide">Slide 16</div>
      <div class="swiper-slide">Slide 17</div>
      <div class="swiper-slide">Slide 18</div>
      <div class="swiper-slide">Slide 19</div>
      <div class="swiper-slide">Slide 20</div>
    </div>
    <!-- Add Pagination -->
    <div class="swiper-pagination"></div>
  </div>
</div>

html,
body {
  position: relative;
  height: 100%;
  overflow: hidden;
}
body {
  background: #eee;
  font-family: Helvetica Neue, Helvetica, Arial, sans-serif;
  font-size: 14px;
  color: #000;
  margin: 0;
  padding: 0;
}
.swiper-container {
  width: 55%;
  height: 100%;
  margin-left: auto;
  margin-right: auto;
}
.swiper-wrapper {
  transition-timing-function: linear !important;
}
.swiper-slide {
  text-align: center;
  font-size: 18px;
  background: #fff;
  height: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
  transition: 0.3s all;
  /*     transform: scale(0.8); */
}

/* .swiper-slide-prev,
.swiper-slide-next,
.swiper-slide-duplicate-prev,
.swiper-slide-duplicate-next {
  transform: scale(0.9)
} */

.swiper-slide-active,
.swiper-slide-duplicate-active {
  transform: scale(1);
  opacity: 1;
}

.mask {
  width: 100%;
  height: 100%;
  mask: linear-gradient(
    to right,
    rgba(0, 0, 0, 0) 0%,
    rgba(0, 0, 0, 1) 20%,
    rgba(0, 0, 0, 1) 80%,
    rgba(0, 0, 0, 0) 100%
  );
}

var swiper = new Swiper(".swiper-container", {
  slidesPerView: 3,
  loop: true,
  centeredSlides: true,
  spaceBetween: 30,
  pagination: {
    el: ".swiper-pagination",
    clickable: true
  },
  speed: 1000,
autoplay: {
    delay: 0,
    enabled: true,
  }
});