void Awake(){

CanvasScaler canvasScaler = GetComponent<CanvasScaler>();

float screenWidthScale = Screen.width / canvasScaler.referenceResolution.x;
float screenHeightScale = Screen.height / canvasScaler.referenceResolution.y;

canvasScaler.matchWidthOrHeight = screenWidthScale > screenHeightScale ? 1 : 0;
}