.burgers
  label.burger.burger1(for="burger1")
    input#burger1.hidden(type="checkbox")
    span
  label.burger.burger2(for="burger2")
    input#burger2.hidden(type="checkbox")
    span
  label.burger.burger3(for="burger3")
    input#burger3.hidden(type="checkbox")
    span
  label.burger.burger4(for="burger4")
    input#burger4.hidden(type="checkbox")
    span
.description Click on the hamburgers to see the action.

:root{
  --color-black: black;
}
.hidden{
  visibility:hidden;position: absolute;   width: 0; height: 0;
}

@function rem($size) {
  $remSize: $size / 16px;
  @return $remSize * 1rem;
}
// The mixin
@mixin menu(
	$width: 1.5rem,
	$height: rem(2),
	$gutter: rem(3),
	$color: white,
	$round: 0,
	$transition-duration: 0.3s
) {
  @if unit($width) == "px" {
    $width: rem($width);
  }
  @if unit($height) == "px" {
    $height: rem($height);
  }
  @if unit($gutter) == "px" {
    $gutter: rem($gutter);
  }

  // Set margins
  $margin: $height + $gutter;
  $margin-left: $width / 2;
  $margin-top: $height / 2;

  // Set specific styles for each bar
  $top: $height + $gutter;

  // set global Variables
  $menu-height: $height !global;
  $menu-gutter: $gutter !global;
  $menu-color: $color !global;
  $menu-margin: $margin !global;
  $menu-margin-left: $margin-left !global;
  $menu-margin-top: $margin-top !global;
  $menu-top: $top !global;

  // The code for the span
  user-select: none;
  position: absolute;
  margin: #{$margin-top} auto #{$margin} -#{$margin-left};
  text-indent: -999em;
  top: 50%;
  left: 50%;
  margin-top: -#{$menu-height/2};
  cursor: pointer;

  // Set styles to bars
  &,
  &:before,
  &:after {
    display: block;
    width: $width;
    height: $height;
    background-color: $color;
    transition: $transition-duration;
    opacity: 1;
    @if $round != 0 {
      border-radius: $round;
    }
  }
  // Bottom and top bar
  &:before,
  &:after {
    position: absolute;
    content: "";
  }

  // Top bar
  &:before {
    top: -#{$top};
  }

  // Bottom bar
  &:after {
    top: #{$top};
  }
}

@mixin menu-close {
  &:before,
  &:after {
    top: 0px;
    margin-top: -#{($menu-height/2) + ($menu-gutter + $menu-height)};
    @content;
  }
  & {
    background-color: transparent;
  }
  &:before {
    transform: translateY($menu-gutter + $menu-height) rotate(45deg);
  }
  &:after {
    transform: translateY($menu-gutter + $menu-height) rotate(-45deg);
  }
}

@mixin menu-close-rtl {
  &:before,
  &:after {
    top: 0px;
    margin-top: -#{($menu-height/2) + ($menu-gutter + $menu-height)};
    @content;
  }
  & {
    background-color: transparent;
  }
  &:before {
    transform: translateY($menu-gutter + $menu-height) rotate(-45deg);
  }
  &:after {
    transform: translateY($menu-gutter + $menu-height) rotate(45deg);
  }
}

@mixin menu-close-rotator {
  &:before,
  &:after {
    top: 0px;
    margin-top: -#{($menu-height/2) + ($menu-gutter + $menu-height)};
    @content;
  }
  & {
    transform: rotate(-360deg);
    background-color: transparent;
  }
  &:before {
    transform: translateY($menu-gutter + $menu-height) rotate(-45deg);
  }
  &:after {
    transform: translateY($menu-gutter + $menu-height) rotate(45deg);
  }
}
@mixin menu-close-middle {
  &:before,
  &:after {
    top: 0px;
    margin-top: -#{($menu-height/2) + ($menu-gutter + $menu-height)};
    @content;
  }
  & {
    animation: menuCloseMiddle--base 0.5s forwards;
  }
  &:before {
    animation: menuCloseMiddle--before 0.5s forwards;
  }
  &:after {
    animation: menuCloseMiddle--after 0.5s forwards;
    @at-root {
      @keyframes menuCloseMiddle--base {
        0% {
          background-color: rgba(0, 0, 0, 1);
        }
        80% {
          background-color: rgba(0, 0, 0, 1);
        }
        100% {
          background-color: rgba(0, 0, 0, 0);
        }
      }
      @keyframes menuCloseMiddle--after {
        0% {
          transform: translateY(0) rotate(0);
        }
        80% {
          transform: translateY($menu-gutter + $menu-height) rotate(0);
        }
        100% {
          transform: translateY($menu-gutter + $menu-height) rotate(45deg);
        }
      }
      @keyframes menuCloseMiddle--before {
        0% {
          transform: translateY(0) rotate(0);
        }
        80% {
          transform: translateY($menu-gutter + $menu-height) rotate(0);
        }
        100% {
          transform: translateY($menu-gutter + $menu-height) rotate(-45deg);
        }
      }
    }
  }
}
@mixin menu-reset {
  &:before,
  &:after {
    margin-top: 0;
    @content;
  }
  & {
    background-color: $menu-color;
  }
  &:before {
    transform: translateY(0) rotate(0deg);
    top: -#{$menu-top};
  }
  &:after {
    transform: translateY(0) rotate(0deg);
    top: #{$menu-top};
  }
}
@mixin menu-body {
  &,
  &:before,
  &:after {
    @content;
  }
}
@mixin menu-body-first {
  &:before {
    @content;
  }
}
@mixin menu-body-middle {
  & {
    @content;
  }
}
@mixin menu-body-last {
  &:after {
    @content;
  }
}

@mixin menu-body-close {
  &:before,
  &:after {
    @content;
  }
}

.burger {
  display: block;
  position: relative;
  width: 3rem;
  height: 3rem;
  border-radius: 3px;
  box-shadow: 0 0 grid(1) rgba(0, 0, 0, 0.25), 0 0 grid(0.2) rgba(0, 0, 0, 0.1);
  background-color: var(--color-white);
  margin: 0.5rem;
  span {
    @include menu(1.5rem, 0.125rem, 0.4rem, var(--color-black));
  }
}
.burgers {
  display: flex;
}
.burger1 {
  input:checked + span {
    @include menu-close();
  }
}
.burger2 {
  input:checked + span {
    @include menu-close-rtl();
  }
}
.burger3 {
  input:checked + span {
    @include menu-close-rotator();
  }
}
.burger4 {
  input:checked + span {
    @include menu-close-middle();
  }
}

///

body,
html {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-flow: wrap;
}
.description {
  width: 100%;
  text-align: center;
  color: rgba(0, 0, 0, 0.25);
}