function cha(){
					document.getElementById("aa1").className="change";
					document.getElementById("aa2").className="nochange";
					document.getElementById("a1").className="about_bot";
					document.getElementById("a2").className="about_bot1";
					}
		function nocha(){
					document.getElementById("aa1").className="change1";
					document.getElementById("aa2").className="change";
					document.getElementById("a2").className="about_bot";
					document.getElementById("a1").className="about_bot1";
					}
					
		 function sec(){
					document.getElementById("pp1").className="pro";
					document.getElementById("pp2").className="nopro1";
					document.getElementById("pp3").className="nopro";
					document.getElementById("pp4").className="nopro1";
					document.getElementById("p1").className="product_bot";
					document.getElementById("p2").className="product_bot1";
					document.getElementById("p3").className="product_bot1";
					document.getElementById("p4").className="product_bot1";
					}
		function nosec(){
					document.getElementById("pp1").className="pro1";
					document.getElementById("pp2").className="pro2";
					document.getElementById("pp3").className="nopro";
					document.getElementById("pp4").className="nopro1";
					document.getElementById("p2").className="product_bot";
					document.getElementById("p1").className="product_bot1";
					document.getElementById("p3").className="product_bot1";
					document.getElementById("p4").className="product_bot1";
					}
	  function nosec1(){
					document.getElementById("pp1").className="pro1";
					document.getElementById("pp2").className="nopro1";
					document.getElementById("pp3").className="pro";
					document.getElementById("pp4").className="nopro1";
					document.getElementById("p2").className="product_bot1";
					document.getElementById("p1").className="product_bot1";
					document.getElementById("p3").className="product_bot";
					document.getElementById("p4").className="product_bot1";
					}
	  function nosec2(){
					document.getElementById("pp1").className="pro1";
					document.getElementById("pp2").className="nopro1";
					document.getElementById("pp3").className="nopro1";
					document.getElementById("pp4").className="pro";
					document.getElementById("p2").className="product_bot1";
					document.getElementById("p1").className="product_bot1";
					document.getElementById("p3").className="product_bot1";
					document.getElementById("p4").className="product_bot";
					}