<div class="container_slider_css">
        <img class="photo_slider_css" src="https://i.pinimg.com/736x/f4/d2/96/f4d2961b652880be432fb9580891ed62.jpg" alt="">
        <img class="photo_slider_css" src="https://funart.pro/uploads/posts/2021-04/1618119326_16-p-kotiki-obnimashki-zhivotnie-krasivo-foto-16.jpg" alt="">
        <img class="photo_slider_css" src="https://cs11.pikabu.ru/post_img/2019/02/04/12/1549312329147951618.jpg" alt="">
      </div>

.container_slider_css {
            margin: 50px auto;
            width: 1427px;
            height: 200px;
            overflow: hidden;
            position: relative;
          }

          .photo_slider_css {
            position: absolute;
            animation: round 9s infinite;
            opacity: 0;
            width: 100%;
          }

          @keyframes round {
            35% {
              opacity: 1;
            }
            50% {
              opacity: 0;
            }
          }
          img:nth-child(1) {
            animation-delay: 0s;
          }

          img:nth-child(2) {
            animation-delay: 3s;
          }

          img:nth-child(3) {
            animation-delay: 6s;
          }