Tryit Editor v2.9

Edit This Code:
<!DOCTYPE html>
<html>
<head>
<script>
function color(color) {
    document.forms[0].myInput.style.background = color;
}
</script>
</head>

<body>

<form>
Write a message:<br>
<input
type="text" 
onkeydown="color('yellow')"
onkeyup="color('white')"
name="myInput">
</form>

</body>
</html>