* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

.img-slider {
    position: relative;
    width: 100vw;
    height: 400px;
}
.img-slider .slider-container {
    position: absolute;
    width: 300%;
    top: 0;
    left: 0;
    overflow: hidden;
    animation: slider 26s infinite;
}
.img-slider .slider-container .slide {
    position: relative;
    width: 33.33333333%;
    height: 100%;
    float: left;
    overflow: hidden
}
.img-slider .slider-container .slide img {
  display: block;
  width: 100%;
  height: 100%;
}
@keyframes slider {
    0%, 25%, 100%{left: 0}
    
    30%, 55%{left: -100%}
    
    60%, 85%{left: -200%}
}