Will a nap ruin my night sleep?
Keep it to 20–30 minutes of sleep (about 30–40 minutes clock time) and finish before ~15:00. That minimizes slow-wave sleep and preserves night sleep.
What if I feel groggy?
Light movement plus a bright environment usually clears inertia in ~10–20 minutes. Avoid immediately opening deep-focus tasks until the first block starts.
Can I stack caffeine with the nap?
A short “coffee nap” (espresso just before lying down) can help some people wake sharper, but skip it if it disrupts night sleep.