### Initializing GamePush Library in JavaScript

Source: https://github.com/megalanthus/defold-gamepush/blob/master/gamepush/manifests/web/engine_template.html

This JavaScript code defines the `onGPInit` callback, which is invoked when the GamePush library is ready. It attempts to initialize GamePush using `window.GamePushLib.init` if available, otherwise it stores the GamePush instance and initialization result globally for later use. It handles both successful initialization and errors via promises.

```JavaScript
window.onGPInit = (gp) => {
  function init(gp, result) {
    if (window.GamePushLib !== undefined && window.GamePushLib.init !== undefined) {
      window.GamePushLib.init(gp, result);
    } else {
      window.GamePushInstance = gp;
      window.GamePushInit = result;
    }
  }
  gp.player.ready.then( function () {
    init(gp, true);
  }).catch( function () {
    init(gp, false);
  });
}
```

--------------------------------

### Applying Full-Screen CSS Styling for Defold

Source: https://github.com/megalanthus/defold-gamepush/blob/master/gamepush/manifests/web/engine_template.html

This CSS snippet ensures the game body occupies the full viewport when the `DEFOLD_SCALE_MODE_IS_NO_SCALE` flag is not set. It removes default margins and padding, making the game canvas fill the entire screen by setting all directional offsets to zero.

```CSS
body { left: 0; right: 0; top: 0; bottom: 0; }
```

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