// JavaScript Document
function chng_bg(obj,clr) {                                    
   obj.style.backgroundColor = clr;                                    
  }


function show_desc(obj) {                          
   if ( document.getElementById(obj).style.display == 'none' ) {                          
    document.getElementById(obj).style.display = 'block';                          
   } else {                          
    document.getElementById(obj).style.display = 'none';                          
   }                          
  }