var strFieldTextColor = "Black";
var strFieldBGColor = "#dbdbdb";

var strFieldTextColorOnFocus = "Black";
var strFieldBGColorOnFocus = "White";

function changeColorOnFocus(obj)
{
   obj.style.color = strFieldTextColorOnFocus;
   obj.style.background = strFieldBGColorOnFocus;
}

function changeColorOnBlur(obj)
{
   obj.style.color = strFieldTextColor;
   obj.style.background = strFieldBGColor;
}