#topnav {
  width: 100%;
  height: 160px;
  position: relative;
}

/* This is art work and applies to ALL elements */

#topnav ul {
    padding: 0; 
    text-decoration:none;
    list-style-type: none; 
    list-style-image: none; 
}
#topnav ul a:hover {
    color: #49ff1f;
}
#topnav ul li a {
    background:#d6f8cc;
    text-decoration:none;
    text-align:center;
    margin-left: 0;
    margin-right: 0;
    text-decoration: none;
    padding: 2px 8px 2px 8px; 
    color: purple;
    box-shadow: 0 0 5px #333333;
    border-radius: 10px;
    background: linear-gradient(top, #efefef, #caf6bb);
}

/* Applies only to top-level (horizontal) menu */
 *
#topnav > ul {
  margin-left: 20%;
  margin-right: auto;
}
#topnav > ul li {
    float: left;        /* Makes the menu horizontal */
}
#topnav > ul li + li {
    margin-left: 3px;	/* Spacing between elements */
}

/* Applies only to SECOND-LEVEL (vertical) sublists */

#topnav ul li ul {
    width: 20px;	/* guarantees the sublist is vertical */
    height: 80px;
    margin-top: 8px;    /* spacing down from main menu */
}
#topnav ul li ul li + li {
    margin-top: 6px;    /* vertical spacing between list elements */
}