?

There are slider variables for the spring's length and stroke, the angle of the lid fully opened, the weight of the lid and the force of the spring, and how far the lid mount point needs to be recessed into the lid.

Then there is the point for the box mount point, which can be moved all around. When it's moved to a point where the spring will not fit, the lines describing the open and closed positions of the spring turn red.

There's also another movable point the shows the forces applied to the lid by gravity and the spring, with a callout showing distance above the box. When gravity overcomes the spring, the gravity vector turns red. When the spring overcomes gravity, its vector turns green.

The angles and lengths should all be accurate, the forces less so.