.navbar button.navbar-toggler .hamburger span {
  background-color: #000000;
  transition: all .3s ease;
  -webkit-transition: all .3s ease;
}
.navbar.navbar-short button.navbar-toggler .hamburger span {
  position: absolute;
  right: 0;
  width: 30px;
  height: 2px;
  border-right: 5px;
  background-color: #fff;
  transition: all .3s ease;
  -webkit-transition: all .3s ease;
}