function catgrid()
{ 
 
 for(i=0 ; i<16 ; i++)
 {
 
  document.getElementsByName('catc1')[i].style.backgroundImage = '';
  document.getElementsByName('catc1')[i].style.fontSize = '';
 
 }
 for(j=0 ; j<20 ; j++)
 {
 
  document.getElementsByName('catc0')[j].style.backgroundImage = '';
  document.getElementsByName('catc0')[j].style.fontSize = '';
 
 }

}