window.onload = function()
{
  var txtSearch= document.getElementById("nav_search");
  if (txtSearch) {
    txtSearch.onfocus = function() {
      if(this.value == "Search") {
        this.value = "";
        }
      }

    txtSearch.onblur = function() {
      if(this.value == "") {
       this.value = "Search";
      } 
    }
  }
}

function change_tab(tab_num) {
  hide_tabs();
	document.getElementById('tab_' + tab_num).style.display = "block";
	document.getElementById('tab_button_' + tab_num).className = "tab_on";
}

function hide_tabs() {
  if (document.getElementById('tab_1')){
    document.getElementById('tab_1').style.display = "none";
    document.getElementById('tab_button_1').className = "tab_off";
  }
  if (document.getElementById('tab_2')){
	  document.getElementById('tab_2').style.display = "none";
    document.getElementById('tab_button_2').className = "tab_off";
  }
  if (document.getElementById('tab_3')){
	  document.getElementById('tab_3').style.display = "none";
    document.getElementById('tab_button_3').className = "tab_off";
  }
  if (document.getElementById('tab_4')){
    document.getElementById('tab_4').style.display = "none";
    document.getElementById('tab_button_4').className = "tab_off";
  }
  if (document.getElementById('tab_5')){
    document.getElementById('tab_5').style.display = "none";
    document.getElementById('tab_button_5').className = "tab_off";
  }
  if (document.getElementById('tab_6')){
    document.getElementById('tab_6').style.display = "none";
    document.getElementById('tab_button_6').className = "tab_off";
  }
	
}