function secBoard(n,x)
{
for(i=0;i<secTable.cells.length;i++){
secTable.cells[i].className="sec1";
secTable.cells[n].className="sec2";}
for(i=0;i<mainTable.tBodies.length;i++){
mainTable.tBodies[i].style.display="none";
mainTable.tBodies[n].style.display="block";}
}