Move a cube with mouse relative to the camera rotation

Basically what I want is to mimic how you can move objects on Unity in my game. For example in Unity you have the following system:

In this system you can move the cube dragging the arrows and the drag movement will be relative to the mouse coordinates X /Y and the camera rotation.

My problem is make it relative to the camera, for example if I looking to the cube in it front and I want to move it with the X arrow to the right the drag movement will be in one direction and if I looking the cube in it back the movement will be in another direction.

How can I make the mouse dragging relative to the camera orientation?