We talked about how you want at least 18+ hours of light and you’ll want watch to your temperatures both when the lights are on and off. It’s best to keep your vegetation temps between 70-85°F (20-30°C).
Cannabis is a hardy plant and can briefly tolerate temps outside this range. In my early days, I fought with heat a lot and had temps that hit the high 90’s for several hours. This was in flowering too, which has a lower temperature range to help trick the plant into thinking it’s fall.
It’s completely fine if you’re daytime and nighttime temps are the same. Some strains, like Blue Mystic, produce a lavender hue on the leaves during flowering, but will only do so if night temps are decently lower than the daytime temps.