Camera following player only at y axis but stops end of background

i want a camera follow player on y axis but when my background end i want to stop camera.
so far i figured out how to follow player on y axis but i cant find out how to make camera just show my background. Its a 2D game

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CameraFollowY : MonoBehaviour {

public Transform target;

void LateUpdate() {
	transform.position = new Vector3(transform.position.x, target.position.y, -10);



transform.position = new Vector3(Mathf.clamp(transform.position.x,levelStartX,levelEndX), target.position.y, -10);