function blink() {
 if (!document.all) return
 if (t.style.backgroundColor!="black") {
  t.style.color="red"
  t.style.backgroundColor="black"
  t2.style.color="red"
  t2.style.backgroundColor="black"
 } else {
  t.style.color="black"
  t.style.backgroundColor="#c6d7c5"
  t2.style.color="black"
  t2.style.backgroundColor="#c6d7c5"
}}
setInterval("blink()", 500)