body {
    background-color:purple ;
 padding-top:0rem;
  background-attachment: scroll;
    background-size: 1700px;
        background-position: top;
        color: rgb(200, 255, 0);
        text-align: left;
        background-repeat: no-repeat;
        font-size: 30px;  
        font-family: Verdana, Geneva, Tahoma, sans-serif;   
    }

ul {
list-style-type: none;
margin: 0;
padding: 3px;
overflow: hidden;
background-color: black;
position: fixed;
top: 0;
width: 100%;
}

li {
float: left;
}

li a {
display: block;
color: rgb(226, 226, 226);
text-align: center;
padding: 14px 16px;
text-decoration:none;
font-size: 20px;
font-family: 'Times New Roman', Times, serif;

}

li a:hover {
background-color: rgb(39, 16, 1);
}
 img{
     display:block;
   margin-left: auto;
   margin-right: auto;
   width: 50%;

 }