Change the background color with onFocus

<FORM>
     <
INPUT TYPE="text" VALUE="red" onFocus="document.bgColor='red'">
     <INPUT TYPE="text" VALUE="green" onFocus="document.bgColor='green'">
    
<INPUT TYPE="text" VALUE="blue" onFocus="document.bgColor='blue'">
    
<INPUT TYPE="text" VALUE="white" onFocus="document.bgColor='white'">
</FORM>