var currentPage;
var activePage;

function getStyleFrom( id ) {
	if( document.all ) {
		return( document.all[ id ].style );
	}
	else if( document.getElementById ) {
		return( document.getElementById( id ).style );
	}
}

function switchPage( page ) {
	activePage = page;
	pageObj = getStyleFrom( page );

	if( !( pageObj == currentPage ) ) {
		if( pageObj.display == "block" ) {
			pageObj.display = "None";
		}
		else {
			pageObj.display = "block";
		}

		closeCurrentPage();
		currentPage = pageObj;
	}
}

function closeCurrentPage() {
	if( currentPage ) {
		currentPage.display = "None";
		currentPage = null;
	}
}