RotateAround reversing doesn't work with negative vector3

Hello, I have some code that is supposed to rotate an ui elements parent (empty gameobject). The rotation works great in one direction and switching to the other directions works as well, but then it gets stuck on one direction. I know it is because the EulerAngles don't recognize negative numbers, but I am unsure how to fix this. I looked through every similiar question on Google, but none fixed the issue.

How do I get the object to switch direction when it hits -70 rotation?

 public GameObject target;
     public int speed = 40;
     public bool ChangeDirection = false;
     public Vector3 leftRotation = new Vector3(0, 0, 70);
     public Vector3 rightRotation  = new Vector3(0, 0, -70);
 
     void Update()
     {
 
         if (!ChangeDirection)
         {
             //Check for direction change
             if (this.transform.rotation.eulerAngles.z > leftRotation.z)
             {
                 ChangeDirection = true;
             }
             //Rotate
             this.transform.RotateAround(target.transform.position, Vector3.forward, speed * Time.deltaTime);
         }
         else if (ChangeDirection)
         {
             //Check for direction change
             if (this.transform.rotation.eulerAngles.z < rightRotation.z) //Issue
             {
                 ChangeDirection = false;
             }
             //Rotate
             this.transform.RotateAround(target.transform.position, Vector3.back, speed * Time.deltaTime);
         }
     }