Added a bunch of stuff

Assets/Scripts/Background.cs

@@ -0,0 +1,43 @@
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+public class Background : MonoBehaviour {
+	SpriteRenderer spriteRenderer;
+
+	void Awake() {
+		spriteRenderer = GetComponent<SpriteRenderer> ();
+
+		StartFade (0.1f);
+	}
+
+	void StartFade(float period) {
+		if (period <= 0) {
+			throw new System.ArgumentOutOfRangeException("StartFade argument must be a positive floating point value");
+		}
+		StartCoroutine (FadeCoroutine (period));
+	}
+
+	IEnumerator FadeCoroutine(float period) {
+		float absolute = 1.0f;
+		float degree = -0.01f;
+		const float lowerLimit = 0.8f;
+		const float upperLimit = 1.0f;
+
+		while(true) {
+			//wait
+			yield return new WaitForSeconds (period);
+
+			//fade routine
+			absolute += degree;
+
+			//flip fade direction
+			if (absolute <= lowerLimit || absolute >= upperLimit) {
+				degree = -degree;
+			}
+
+			//fade
+			spriteRenderer.color = new Color (absolute, absolute, absolute);
+		}
+	}
+}