I need writing ideas!?

The Four Elements of ancient Greek science (and thus ancient European science) were Earth, Air, Fire, and Water.

How does the world, and how do the temples "revolve around" the four elements? What do you mean by "revolve around"? That the source of the magic is one element, or a combination of elements, or the interaction of two or more elements (water plus fire equal steam [affecting the element Air] or boiling water [Fire affecting Water] or extinguishing Fire by Water, make Fire's magic ineffective.)? Or do you mean that the physical temple revolves around the element like the planets revolve around the Sun or, in ancient cosmology, the Sun and stars revolve around the Earth?

How would your magic temples look?. What magical implements, relics and icons would be on each altar? What clothing do the priests and worshippers wear? What rituals do they perform? What hymns do they chant?  Your imagination and some research is needed.  Have you been to a Catholic, Orthodox or High Church of England worship service?  If Covid-19 restrictions permit, attend a few so you can see inside the church (the stained glass is awesome) and experience what a ritual is like. If restrictions permit, see if you can attend a Wiccan or pagan ceremony or an Indiginous peoples' ceremony.

Or see if YouTube has videos recording ceremonies, services, masses and other rituals.

Or read about how the ancient Egyptians and other cultures worshipped. Temples are places where the gods are worshipped, so you should experience how worship was performed.

Simply build an actual-sized, 1:1 model of one of these temples of yours, take lots of pics of it when it's finished and illustrate your "story" with them. Yes, and you could even be in the pictures yourself, looking out of a temple window, say, and waving to your readers. Or reader, probably. Hope this helped.

If you plan to write a story, all these things have to come from YOU.  No-one else.

If you can't manage that, you're not ready to write a story at all.