body{
    margin: 35px auto;
    background-color: black;
}
a{
    display: block;
    text-decoration: none;
    color: black;
}
a:hover{
background-color: blue;
color: white;
}
nav{
     margin: 35px auto;
    width: 460px;
    height: 25px;
}
li{
    list-style-type: none;;
    line-height: 25px;
    height: 25px;
    width: 100px;
    float: left;
    margin-left: 15px;
    text-align: center;
    background-color: purple;
}
@media only screen and (max-width=1000px){
nav li{
    clear: left;
margin: 0px 0px 20px 20px;
background-color: red;
color: white
}
}