//pagination control
					function showLayer(pageId){
						//select video list page
						var contentDiv = document.getElementById('contents');
						var divCollection = contentDiv.getElementsByTagName('div');
						for(i=0; i<divCollection.length; i++) {
							var divLayer = divCollection.item(i);
							if(divLayer.id.indexOf("tab_")!=-1) {
								if(divLayer.id == "tab_"+pageId)
									divLayer.style.display = "block";
								else
									divLayer.style.display = "none";
							}
						}
						//select pagination
						var contentDiv = document.getElementById('contents');
						var divCollection = contentDiv.getElementsByTagName('div');
						for(i=0; i<divCollection.length; i++){
							var divLayer = divCollection.item(i);
							if(divLayer.id.indexOf("nav_")!=-1){
								if(divLayer.id == "nav_"+pageId)
									divLayer.style.display = "block";
								else
									divLayer.style.display = "none";
							}
						}
					}
					//show navigation tab
					function showTabName(tabId){
						var tabList = document.getElementById('tabnav');
						for(i=0; i<tabList.childNodes.length; i++){
							if(tabList.childNodes[i].nodeName=="LI"){
								var list = tabList.childNodes[i];
								if(list.id == tabId) {
									list.className = "active";
								} else {
									list.className = "";
								}
							}
						}
						showLayer(tabId+"1"); //show video list page and pagination
						
					}
					//ad