ntainer').show();
      $('#copyable-link').select();
    }
    $('#copyable-link').blur(function(){
      $('#link-container').hide();
    });

    // If the user already specified
    $(function(){
      var expression_base64 = getQueryVariable('expression');
      console.log(expression_base64);
      if( expression_base64 ) {
        $('#equation-input').val( atob(expression_base64.replace('/', '')) );
      }
    });

    // Get things started.
    $('#equation-input').change( update_expression );
    