i currently have a button that plays and stops music the same button.
how do i make it change appearance when it has stoped the music?

//MUSIC

var music: Sound = new Sound(new URLRequest("beach.mp3"));
var sc: SoundChannel;
var isplaying:Boolean = false;

stopbtn.addEventListener(MouseEvent.CLICK, stopMusic);

function stopMusic(E:Event):void
{
sc.stop();
isplaying = false;
}

playbtn.addEventListener(MouseEvent.CLICK, playMusic);

function playMusic(E:Event):void
{
if (!isplaying)
{
sc = music.play();
isplaying = true;
}
else
{
sc.stop();
isplaying = false;
}
}



this is my code for now.