You wrote: “Use your brain” and prove it.”
__________
Seems to me people who believe in the supernatural have the burden of proof. As Karl Popper would explain, we can never know for sure there are no pink horses, because it could be we just haven’t run across one yet. But we can still assert as fact there is no proof of pink horses, and we are justified in believing it to be true, unless and until someone produces one. I like the chances there is no supernatural entity for the same reason. I say religion is based on hope and superstition, and say you have the burden of proof.
Your assertion was not that there is no proof of heaven; your assertion is that "there is no such thing."
"and we are justified in believing it to be true, unless and until someone produces one."
Again, you haven't stated that you believe there is no such thing as heaven; you have indeed stated that
"once your vitals stop, you no longer exist. Period."
There is no declaration of belief in the above sentence. You have stated your assertion as fact. As such, the burden of proof remains on you...and I once again urge you to back up your assertion with proof.