@media only screen and (max-width: 768px) {
    /* For mobile phones: */
    #menu {
      min-width: inherit !important;
    }
  
    .top-banner {
      display: none;
    }
  }

#menu {
    border-bottom: 2px solid black;
    background-color:#fff;
    width: 100%;
    z-index: 1;
    overflow: hidden;
    min-width: 700px;
}

.pure-menu {
    border-right: 2px solid black;   
    width:200px;
    float: left;
    overflow: auto;
    padding: 5px;
}

.pure-menu-list {
    padding-bottom: 10px;
}

.top-banner {
    padding: 5px;
    float: left;
    width: 400px;
    bottom: 1px;
}

.pure-menu-heading {
    margin-bottom: 1em;
    border-bottom: 2px solid black;
}