$(document).ready(function(){     
	var urlImgGSC = $("input[class='requette']").css('background-image');
  if($("input[class='requette']").val() != ''){    
    $("input[class='requette']").css('background-image', 'none');
  };
  $("input[class='requette']").focus(function () {
    $(this).css('background-image', 'none');
  })
  .blur(function () {
    if($(this).val() == ''){    
      $(this).css('background-image', urlImgGSC);
    }
  }); 
});