Rapid reservoir-energy depletion and a low primary recovery factor constrain shale oil development in the Qintong Depression. This study proposes a hybrid CO₂ injection method that combines continuous flooding with cyclic huff-n-puff. Coreflooding experiments with online nuclear magnetic resonance monitoring and compositional numerical simulations were used to identify the recovery mechanisms and optimize the operating parameters for the Luye-1 well block. The core experiment demonstrated the incremental recovery and compositional evolution occurring when cyclic huff-n-puff was applied after continuous CO₂ flooding. Separately, the numerical simulations indicated that the hybrid strategy provided a larger CO₂-contact area and a longer residence time than the individual injection strategies under the modeled conditions. The experiments also showed the sustained recovery of heavier hydrocarbons during successive cycles. A differentiated fracture-network design reduced inter-well gas channeling while maintaining reservoir contact. The selected engineering strategy comprised two asynchronous huff-n-puff cycles followed by hybrid injection, with a flooding-well injection rate of 80 t/d, a cyclic CO₂ injection volume of 7000 t per huff-n-puff well, and a soaking time of 60 days. Under the evaluated model scenario, the joint simulation of this complete parameter combination yielded a recovery-factor increase of 7.76 percentage points and a final recovery factor of 14.19%, with a gas-utilization efficiency of 0.160 t_oil/t_CO2. These scenario-based results suggest the potential of hybrid CO₂ injection for reservoir-energy replenishment and enhanced shale oil recovery.