#navwrap.affix {
  top: 0;
  background: none;
  width: 100%;
  z-index: 1000;
  left: 0;
  position: fixed;
}
#navwrap.affix .zen-container {
  background: rgba(0,0,0,0.8);
  padding: 10px 30px;
}
#navwrap.affix ul {
  margin-bottom: 0;
}