.slider {
    width: 100%;
    margin: auto;
    overflow: hidden;
    position: relative;
}

.slider ul {
    display: flex;
    padding: 0;
    width: 400%;
    
    animation: cambio 20s infinite;
    animation-direction: alternate;
    transition-timing-function: ease-in;
}

.slider li {
    width: 100%;
    list-style: none;
}

.slider img {
    width: 100%;
}

.slider .description1 {
    padding: 20px;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translateX(-50%) translateY(-50%);
    z-index: 10;
}

.slider .description2 {
    padding: 20px;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translateX(-50%) translateY(-50%);
    z-index: 20;
}


@keyframes cambio {
    0% { margin-left: 0; }
    20% { margin-left: 0; }
    
    25% { margin-left: -100%; }
    45% { margin-left: -100%; }
    
    50% { margin-left: -200%; }
    70% { margin-left: -200%; }
    
    75% { margin-left: -300%; }
    100% { margin-left: -300%; }
}

@media (max-width:767px) {
    .slider {
        margin-top: 70px;
    }
    
    .slider img{
        height: 150px;
    }
}

@media (min-width:1024px) {
    .slider {
        width: 100%;
        margin: auto;
        overflow: hidden;
        position: relative;
        top: 78px;
    }
}