anchor.diff:  .box {
     height: 200px;
     width: 200px;
  -  background-color: grey;
  +  background-color: lightgreen;
     /*margin:20px;*/
     border:1px solid black;
     display: inline-block;
  
positive.code:   $.get('/sg/move?game_id=<%=sesh[:game_id]%>&box='+id+'&phase='+window.phase).success(r=> {
      $('.box.'+id).html(r.val);
      setTimeout(()=> {
        $('.box').html('')
      },1000);
    })
  }
  
negative.code:   cursor: not-allowed;
  }
  .box.disabled {
    background-color: darkgrey;
    color:white;
  }
  .sample_or_choose {
    background-color: lightblue;
  