MVP1/Assets/Scripts/Camera/CameraZoom.cs

using UnityEngine;

public class CameraZoom : MonoBehaviour
{
    public Camera targetCamera; 
    private float lastCameraSize;

    void Start()
    {
        
        if(targetCamera == null)
        targetCamera = Camera.main;

        lastCameraSize = targetCamera.orthographicSize;
        UpdateCanvasScale();
    }
    void LateUpdate()
        {
        if (Mathf.Abs(targetCamera.orthographicSize - lastCameraSize) > 0.01f)        {
            lastCameraSize = targetCamera.orthographicSize;
            UpdateCanvasScale();
        }
    }

    void UpdateCanvasScale()
    {
        float scaleFactor = 10f / targetCamera.orthographicSize;

        transform.localScale = Vector3.one * scaleFactor;
    }
    
}