*{
    padding:0;
    margin: 0;   
}

.slider {
    margin: auto;
    margin-top: 15px;
    margin-bottom: 15px;
    width: 95%;
    height: 100%;
    background-color: aqua;
	overflow: hidden;
    /*border: 5px;
    border-style: groove;
    border-color: steelblue;*/
    position: relative;
    z-index: -3;
}

.slider ul {
    width: 400%;
	display: flex;
	animation: cambio 20s infinite alternate linear;
}

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

.slider img {
    padding: 0;
	width: 100%;
    height: 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%;}
}


/* RESPONSIVE DESIGN -- media screen and (max-width: 520px) and (min-width: 480px) */

@media only screen and (min-width : 250px) and (max-width : 480px)
{
    .slider {
    margin: auto;
    /*margin-top: 15px;
    margin-bottom: 15px;*/
    width: 100%;
    height: 100%;
    background-color: aqua;
	overflow: hidden;
    z-index: -3;
}
    
}