var CurrentItem = 0;
var NavigationTabPrefix = 'Tab';
var ContentTabPrefix = 'Content';

var No = 0;
var Yes = 1;

var ActiveTabClasses = ['DarkBlueRightBorder Active', 
                        'WhiteLeftBorder DarkBlueRightBorder Active', 
                        'WhiteLeftBorder DarkBlueRightBorder Active', 
                        'WhiteLeftBorder DarkBlueRightBorder Active', 
                        'WhiteLeftBorder WhiteRightBorder Active'];

var InactiveTabClasses = ['DarkBlueRightBorder Inactive', 
                          'WhiteLeftBorder DarkBlueRightBorder Inactive', 
                          'WhiteLeftBorder DarkBlueRightBorder Inactive', 
                          'WhiteLeftBorder DarkBlueRightBorder Inactive', 
                          'WhiteLeftBorder WhiteRightBorder Inactive'];

var ContentClasses = ['HiddenContent', 'VisibleContent'];

function Display(ItemNumber)
{
   if(ItemNumber >= 0)
   {
      Hide(CurrentItem);
      CurrentItem = ItemNumber;
      Show(CurrentItem);
   }
}

function Show(ItemNumber)
{
   if(ItemNumber >= 0)
   {  
      var TargetTab = document.getElementById(NavigationTabPrefix + ItemNumber);
      var TargetContent = document.getElementById(ContentTabPrefix + ItemNumber);
      TargetTab.className = ActiveTabClasses[ItemNumber];
      TargetContent.className = ContentClasses[Yes];
   }
}

function Hide(ItemNumber)
{
   if(ItemNumber >= 0)
   { 
      var TargetTab = document.getElementById(NavigationTabPrefix + ItemNumber);
      var TargetContent = document.getElementById(ContentTabPrefix + ItemNumber);
      TargetTab.className = InactiveTabClasses[ItemNumber];
      TargetContent.className = ContentClasses[No];
   }
}