function nov(){
    var ig=(s_header.style.backgroundPosition.indexOf("px"," "));
    apos=Number(s_header.style.backgroundPosition.substr(0,ig));
    var posdif= Math.round(trgt_pos-apos);
    if(Math.abs(posdif)>10){
        apos+=Math.round(posdif/5);
        s_header.style.backgroundPosition=apos+'px 60px';
    }else{	
    s_header.style.backgroundPosition=trgt_pos+'px 60px';
        clearInterval(window.int_nov);		
    }
}
rollServicesBg=function(No){
    s_header=document.getElementById("services_header");
    trgt_pos=-480*No;
	clearInterval(window.int_nov);	
    window.int_nov=window.setInterval(nov, 33);
}