How do i get a reverse rotation happening on right click down

This is what i have so far, only rotates one way on left click down, need it to do the opposite in the same script can anyone give me a hand?

using UnityEngine; using System.Collections;

public class ArmRotation : MonoBehaviour {

     public float force=20;
     public float speed=10000;
     
     private HingeJoint2D joint;
     private JointMotor2D motor1;
     
     void Start()
     {
         joint = GetComponent<HingeJoint2D>(); // Get hingejoint
         
         motor1.motorSpeed = speed;
         motor1.maxMotorTorque = force;
         
         joint.motor = motor1;
         joint.useMotor = false;
     }
     
     void Update ()
     {
         if(Input.GetMouseButtonDown(0))
         {
             joint.useMotor = true;
         }
         if(Input.GetMouseButtonUp(0))
         {
             joint.useMotor = false;
         }
     }

 }