#nav-icon{
  width: 35px;
  height: 35px;
  -webkit-transform: rotate(0deg);
  -moz-transform: rotate(0deg);
  -o-transform: rotate(0deg);
  transform: rotate(0deg);
  -webkit-transition: .5s ease-in-out;
  -moz-transition: .5s ease-in-out;
  -o-transition: .5s ease-in-out;
  transition: .5s ease-in-out;
  cursor: pointer;
}


#nav-icon {
}

#nav-icon span {
  display: block;
  position: absolute;
  height: 3px;
  width: 50%;
  opacity: 1;
  -webkit-transform: rotate(0deg);
  -moz-transform: rotate(0deg);
  -o-transform: rotate(0deg);
  transform: rotate(0deg);
  -webkit-transition: .25s ease-in-out;
  -moz-transition: .25s ease-in-out;
  -o-transition: .25s ease-in-out;
  transition: .25s ease-in-out;
}

#nav-icon span:nth-child(even) {
  left: 50%;
}

#nav-icon span:nth-child(odd) {
  left:0px;
}

#nav-icon span:nth-child(1), #nav-icon span:nth-child(2) {
  top: 0px;
}

#nav-icon span:nth-child(3), #nav-icon span:nth-child(4) {
  top: 8px;
}

#nav-icon span:nth-child(5), #nav-icon span:nth-child(6) {
  top: 16px;
}

#nav-icon.open span:nth-child(1),#nav-icon.open span:nth-child(6) {
  -webkit-transform: rotate(45deg);
  -moz-transform: rotate(45deg);
  -o-transform: rotate(45deg);
  transform: rotate(45deg);
}

#nav-icon.open span:nth-child(2),#nav-icon.open span:nth-child(5) {
  -webkit-transform: rotate(-45deg);
  -moz-transform: rotate(-45deg);
  -o-transform: rotate(-45deg);
  transform: rotate(-45deg);
}

#nav-icon.open span:nth-child(1) {
  left: 5px;
  top: 4px;
}

#nav-icon.open span:nth-child(2) {
  left: calc(50% - 5px);
  top: 4px;
}

#nav-icon.open span:nth-child(3) {
  left: -50%;
  opacity: 0;
}

#nav-icon.open span:nth-child(4) {
  left: 100%;
  opacity: 0;
}

#nav-icon.open span:nth-child(5) {
  left: 5px;
  top: 12px;
}

#nav-icon.open span:nth-child(6) {
  left: calc(50% - 5px);
  top: 12px;
}