Air carrier First Officer reported temporary loss of control due to severe turbulence during cruise.

Narrative

Enroute to Houston we were getting reroutes to avoid a line of thunderstorms between ZZZ and Houston. We got cleared to LAURL which is close to 50nm off the coast and then got deviations for thunderstorms. We asked for FL360 and made right deviations to stay closer to the coastline. ATC was saturated with aircraft requesting deviations. We had weather radar on and saw a gap that was VMC and no red but some green on the radar at 0-degree tilt and 12nm on my screen and 25nm on the pilot flying screen. We were using the deviations to avoid the green on the radar and experiencing smooth flight. There was a small patch of green that was up ahead that we would have to go through on that route of flight to avoid bigger patches; I suggested slowing to .63M; PF said he wanted to keep it fast. I zoomed radar into 5nm and saw that the green was growing and that verbally announced that we were going to get some heavy turbulence in a few seconds. The severe turbulence hit and the aircraft was pitched up and knocked the auto pilot off. We corrected from an unusual attitude and attempted to maintain a level pitch attitude. As the turbulence continued; we eventually got pushed into a nose down attitude and max speed and master warning sounded off airspeed got to maybe 330kts. I pulled back the throttle and we both pulled the yoke back to bring the aircraft to level and recover from the unusual attitude. We were still in a descent when we exited the cloud attempted to return to FL360 but the aircraft continued to descent to FL350; I contacted ATC and notified them of the severe turbulence and requested FL340 as we attempted to reengage auto pilot that was not capturing FL350; the aircraft leveled at FL340 but seemed to be wanting to pitch down still. PF requested FL280 to exit RVSM airspace and ATC gave it to us. We descended to FL280 with autopilot engaged and it captured FL280 fine for level off.With the aircraft under control; we notified ATC we were continuing on flight plan and made a passenger announcement and called out flight attendant to see if there was anyone injured. No one was hurt and we continued on route of flight. The duration of the turbulence lasted for maybe a minute with the recovery from unusual attitude lasting two minutes and then descent to FL280 ten minutes after we encountered the turbulence. As we got level and monitored the aircraft systems; we looked at the QRH for max over speed and ran that checklist. We let dispatch know of the turbulence and that there were no injuries. Continued the flight monitoring the flight controls of possible damage and had no other issue on the flight. We also had a strong smell of what was possibly a lightning strike.We were getting close to being stuck 50nm out on the coast and thought we had a good gap to go through. Should have done a better job of communicating with ATC asking them if they saw any routes on the flight. I also could have been sterner with my request for .63M and about what I saw on the radar although by the time we saw the green we may have been unable to avoid it. Next time I would avoid deviating that closely.