<button class="menu-2">
  Menu
  <span></span>
  <span></span>
  <span></span>
</button>

.menu-2 {
  appearance: none;
  position: absolute;
  right: 50%;
  top: 100px;
  transform: translateX(-50%);
  width: 28px;
  height: 18px;
  font-size: 0;
  padding: 0;
  border: 0;
  background: transparent;
  cursor: pointer;
  
  &:after {
    content: "";
    position: absolute;
    left: -12px;
    top: -16px;
    z-index: -1;
    width: 50px;
    height: 50px;
    background: #E83474;
    border-radius: 7px;
    opacity: 0.5;
    transition: 0.3s ease-out;
  }
  
  span {
    display: block;
    width: 100%;
    height: 3px;
    background: #000;
    margin-bottom: 5px;
    border-radius: 5px;
    transition: 0.3s ease-out;
  }
  
  &:hover {
    span {
      background: #fff;
    }
    
    &:after {
      opacity: 1;
    }
  }
}

document.querySelector('.menu').addEventListener('click', function(){
  alert('clicked!');
});