html {
    position: relative;
    min-height: 100%;
  }

footer {
    position: absolute;
    bottom: 0;
    width: 100%;
    background-color: #f5f5f5;
}

.navbar-nav li:hover > ul.dropdown-menu {
  display: block;
}
.dropdown-submenu {
  position:relative;
}
.dropdown-submenu>.dropdown-menu {
  top: 0;
  left: 100%;
  margin-top:-6px;
}

/* rotate caret on hover */
.dropdown-menu > li > a:hover:after {
  text-decoration: underline;
  transform: rotate(-90deg);
}