Shrinking-pie bargaining

1. The proposer offers a whole-dollar share of the current pot to the other player, who explicitly accepts or rejects.
2. Acceptance pays the offer to the responder and the rest to the proposer. Rejection reduces the pot by a fixed amount and switches roles.
3. The final rejection completes the negotiation with zero for both. A missing response instead makes it incomplete. Roles are assigned randomly at the start of each game.
4. This is a finite proposal-count variant with fixed losses, not the infinite-horizon Rubinstein model. Current and initial pot sizes are shown separately.

All $ amounts are virtual game dollars.