anchor.diff:  </section>
   
   <section>
  -<div class='box 1' onclick=onBoxClick(1)> 10 </div>
  -<div class='box 2' onclick=onBoxClick(2)> 20 </div>
  -<div class='box 3' onclick=onBoxClick(3)>    </div><div class='box 4' onclick=onBoxClick(4)> 40 </div>
  +<div class='box 1' onclick=onBoxClick(1)> 1 </div>
  +<div class='box 2' onclick=onBoxClick(2)>  </div>
  +<div class='box 3' onclick=onBoxClick(3)>  2  </div>
  +<div class='box 4' onclick=onBoxClick(4)>  </div>
   </section>
   <script>
   log = console.log
  
positive.code:   /*margin:20px;*/
    border:1px solid black;
    display: inline-block;
  }
  .disabled {
    cursor: not-allowed;
  
negative.code:     debugger
      $('.box.'+id).html(r.val);
      setTimeout(()=> {
        $('.box').html('')
      },1000);
    })
  }
  