.mainmenu, .submenu {
  list-style: none;
  padding: 0;
  margin: 0;
}

.mainmenu a {
  display: block;
  background-color: #B71C1C;
  text-decoration: none;
  padding: 5px;
  color: #fff;
}

.mainmenu a:hover {
    background-color: #E65F5F;
    list-style:none
}

.mainmenu ul li {
    list-style: none;
}

.mainmenu li:hover .submenu {
  display: block;
  max-height: 100%;
}

.submenu a {
  background-color: transparent;
  color: #000;
}

.submenu a:hover {
  background-color: #E65F5F;
}

.submenu {
  overflow: hidden;
  max-height: 0;
  -webkit-transition: all 0.2s ease-out;
}