styles.xml https://github.com/euv921/android101-now/blob/master/app/src/main/res/values/styles.xml
activity_main.xml https://github.com/euv921/android101-now/blob/master/app/src/main/res/layout/activity_main.xml
MainActivity.java https://github.com/euv921/android101-now/blob/master/app/src/main/java/com/pinterest/hello/myapplication/MainActivity.java
activity_game_over.xml https://github.com/euv921/android101-now/blob/master/app/src/main/res/layout/activity_game_over.xml
GameOverActivity.java https://github.com/euv921/android101-now/blob/master/app/src/main/java/com/pinterest/hello/myapplication/GameOverActivity.java