function tab_select(self) {
				if (self.id == "overview") {
					document.getElementById("centerpiece").style.backgroundPosition = "0 0";
					document.getElementById("overview-tab").style.display = "block";
					document.getElementById("community-tab").style.display = "none";
					document.getElementById("association-tab").style.display = "none";
					document.getElementById("organization-tab").style.display = "none";
					document.getElementById("support-tab").style.display = "none";
					document.getElementById("features-tab").style.display = "none";
				}
				if (self.id == "community") {
					document.getElementById("centerpiece").style.backgroundPosition = "0 -400px";
					document.getElementById("overview-tab").style.display = "none";
					document.getElementById("community-tab").style.display = "block";
					document.getElementById("association-tab").style.display = "none";
					document.getElementById("organization-tab").style.display = "none";
					document.getElementById("support-tab").style.display = "none";
					document.getElementById("features-tab").style.display = "none";
				}
				if (self.id == "association") {
					document.getElementById("centerpiece").style.backgroundPosition = "0 -800px";
					document.getElementById("overview-tab").style.display = "none";
					document.getElementById("community-tab").style.display = "none";
					document.getElementById("association-tab").style.display = "block";
					document.getElementById("organization-tab").style.display = "none";
					document.getElementById("support-tab").style.display = "none";
					document.getElementById("features-tab").style.display = "none";
				}
				if (self.id == "organization") {
					document.getElementById("centerpiece").style.backgroundPosition = "0 -1200px";
					document.getElementById("overview-tab").style.display = "none";
					document.getElementById("community-tab").style.display = "none";
					document.getElementById("association-tab").style.display = "none";
					document.getElementById("organization-tab").style.display = "block";
					document.getElementById("support-tab").style.display = "none";
					document.getElementById("features-tab").style.display = "none";
				}
				if (self.id == "support") {
					document.getElementById("centerpiece").style.backgroundPosition = "0 -1600px";
					document.getElementById("overview-tab").style.display = "none";
					document.getElementById("community-tab").style.display = "none";
					document.getElementById("association-tab").style.display = "none";
					document.getElementById("organization-tab").style.display = "none";
					document.getElementById("support-tab").style.display = "block";
					document.getElementById("features-tab").style.display = "none";
				}
				if (self.id == "features") {
					document.getElementById("centerpiece").style.backgroundPosition = "0 -2000px";
					document.getElementById("overview-tab").style.display = "none";
					document.getElementById("community-tab").style.display = "none";
					document.getElementById("association-tab").style.display = "none";
					document.getElementById("organization-tab").style.display = "none";
					document.getElementById("support-tab").style.display = "none";
					document.getElementById("features-tab").style.display = "block";
				}
				
				
			}