css fold out menu not closing after clicking : I have created a simple fold out menu. When i click on menu icon, **menu opens**.

Now when i click on any option, it should get closed which is not happening. 
Please help, below is my code in [codepen][1]
> Please provide solution using css only. I do not wish to use js.


  [1]: https://codepen.io/ersaurabh101/pen/yjaOgv

`html code`

    <nav role="navigation">
      <div id="menuToggle">
        <!--
        A fake / hidden checkbox is used as click reciever,
        so you can use the :checked selector on it.
        -->
        <input type="checkbox" />
        
    
        <span></span>
        <span></span>
        <span></span>
        
    
        <ul id="menu">
          <a href="#"><li>Home</li></a>
          <a href="#"><li>About</li></a>
          <a href="#"><li>Info</li></a>
          <a href="#"><li>Contact</li></a>
          <a href="https://erikterwan.com/" target="_blank"><li>Show me more</li></a>
        </ul>
      </div>
    </nav>


`css code`

    body
    {
      margin: 0;
      padding: 0;
      
      /* make it look decent enough */
      background: #232323;
      color: #cdcdcd;
      font-family: "Avenir Next", "Avenir", sans-serif;
    }
    
    a
    {
      text-decoration: none;
      color: #232323;
      
      transition: color 0.3s ease;
    }
    
    a:hover
    {
      color: tomato;
    }
    
    #menuToggle
    {
      display: block;
      position: relative;
      top: 50px;
      left: 50px;
      
      z-index: 1;
      
      -webkit-user-select: none;
      user-select: none;
    }
    
    #menuToggle input
    {
      display: block;
      width: 40px;
      height: 32px;
      position: absolute;
      top: -7px;
      left: -5px;
      
      cursor: pointer;
      
      opacity: 0; /* hide this */
      z-index: 2; /* and place it over the hamburger */
      
      -webkit-touch-callout: none;
    }
    
    /*
     * Just a quick hamburger
     */
    #menuToggle span
    {
      display: block;
      width: 33px;
      height: 4px;
      margin-bottom: 5px;
      position: relative;
      
      background: #cdcdcd;
      border-radius: 3px;
      
      z-index: 1;
      
      transform-origin: 4px 0px;
      
      transition: transform 0.5s cubic-bezier(0.77,0.2,0.05,1.0),
                  background 0.5s cubic-bezier(0.77,0.2,0.05,1.0),
                  opacity 0.55s ease;
    }
    
    #menuToggle span:first-child
    {
      transform-origin: 0% 0%;
    }
    
    #menuToggle span:nth-last-child(2)
    {
      transform-origin: 0% 100%;
    }
    
    /* 
     * Transform all the slices of hamburger
     * into a crossmark.
     */
    #menuToggle input:checked ~ span
    {
      opacity: 1;
      transform: rotate(45deg) translate(-2px, -1px);
      background: #232323;
    }
    
    /*
     * But let's hide the middle one.
     */
    #menuToggle input:checked ~ span:nth-last-child(3)
    {
      opacity: 0;
      transform: rotate(0deg) scale(0.2, 0.2);
    }
    
    /*
     * Ohyeah and the last one should go the other direction
     */
    #menuToggle input:checked ~ span:nth-last-child(2)
    {
      transform: rotate(-45deg) translate(0, -1px);
    }
    
    /*
     * Make this absolute positioned
     * at the top left of the screen
     */
    #menu
    {
      position: absolute;
      width: 300px;
      margin: -100px 0 0 -50px;
      padding: 50px;
      padding-top: 125px;
      
      background: #ededed;
      list-style-type: none;
      -webkit-font-smoothing: antialiased;
      /* to stop flickering of text in safari */
      
      transform-origin: 0% 0%;
      transform: translate(-100%, 0);
      
      transition: transform 0.5s cubic-bezier(0.77,0.2,0.05,1.0);
    }
    
    #menu li
    {
      padding: 10px 0;
      font-size: 22px;
    }
    
    /*
     * And let's slide it in from the left
     */
    #menuToggle input:checked ~ ul
    {
      transform: none;
    }




Please provide solution using css only. Thank you for your time.