   }
 }
 
+// Handle clicks on right button to navigate title screen items.
 byte titleMenuRightButton(byte selectedItem) {
-  /**
-     Handle clicks on the right button
-     to navigate through main menu items.
-  */
-
   switch (selectedItem) {
     case TITLE_PLAY_GAME:
       drawRectAroundPlayMenuOption(0);

    isInitialTitleScreen = false;
  }

  byte selectedItem = TITLE_PLAY_GAME;
  unsigned long totalDelay = 0;
  long lastDebounceTime = millis();  // the last time the button was pressed
  byte shipTone = 100;
  float earthY = 56;
    
  for (float y = 64; y > 16; y -= 0.2f) {

    }
}

// Stop any music that is currently playing.
void stopMusic(){
  arduboy.tunes.stopScore();
}

// Determine whether to play A button shoot tone.
bool shouldPlayAButtonTone() {
  return (inGameAButtonLastPress > (inGameFrame - 20));
}

// Determine whether to play B button shoot tone.
bool shouldPlayBButtonTone() {
  return (inGameBButtonLastPress > (inGameFrame - 50));
}

/*******************************************************************************
 * UTILITY FUNCTIONS                                                           *
 *******************************************************************************/

// Redraw the screen.
void display() {
  arduboy.display();
}

// Display message at specified location in specified font size.
void printText(char *message, byte x, byte y, byte textSize) {
  arduboy.setCursor(x, y);
  arduboy.setTextSize(textSize);
  arduboy.print(message);
}

// Redraw the screen after a short delay.
void delayAndDisplay() {
  delay(250);
  display();
}

// Use a typewriter effect to display characters from the bitmap font.
void drawChrs(byte cPos, byte yPos, const uint8_t *letters, unsigned long delayTimer) {
  byte curs = cPos,
       strLen = pgm_read_byte(letters),
