*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
.play{
    width: 90%;
    max-width: 1680px;
    margin: auto;
    overflow: hidden;   
}
.play ul{
    display: flex;
    padding: 0;
    width: 400%;
    margin-top: 6px;
    
    animation: cambio 20s infinite alternate linear;
}
.play li{
    width: 100%;
    list-style: none;
}
.play img{
    width: 100%;
}
@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%;}
            
}