// TAB1_1
function tab_1(num)
{
document.getElementById("tab"+num+"").setAttribute("background", "images/design/tab"+num+"_1bg.jpg")
document.getElementById("tab"+num+"_1").style.display="block"
document.getElementById("tab"+num+"_2").style.display="none"
}

// TAB1_2
function tab_2(num)
{
document.getElementById("tab"+num+"").setAttribute("background", "images/design/tab"+num+"_2bg.jpg")
document.getElementById("tab"+num+"_2").style.display="block"
document.getElementById("tab"+num+"_1").style.display="none"
}