.item-1,
.item-2,
.item-3 {
    position: absolute;

    animation-duration: 20s;
    animation-timing-function: ease-in-out;
    animation-iteration-count: infinite;
}

.item-1{
    animation-name: anim-1;
}

.item-2{
    animation-name: anim-2;
}

.item-3{
    animation-name: anim-3;
}

@keyframes anim-1 {
    0%, 8.3% { left: -100%; opacity: 0; }
    8.3%,25% { left: 25%; opacity: 1; }
    33.33%, 100% { left: 110%; opacity: 0; }
}

@keyframes anim-2 {
    0%, 33.33% { left: -100%; opacity: 0; }
    41.63%, 58.29% { left: 25%; opacity: 1; }
    66.66%, 100% { left: 110%; opacity: 0; }
}

@keyframes anim-3 {
    0%, 66.66% { left: -100%; opacity: 0; }
    74.96%, 91.62% { left: 25%; opacity: 1; }
    100% { left: 110%; opacity: 0; }
}