Here is the situation. A planet fairly similar to Earth is orbiting binary stars, one O or B type and one F type. Sometimes the stars are close together in the sky, sometimes far apart, sometimes only one is visible, and sometimes one eclipses the other. The atmosphere is 56% nitrogen, 40% oxygen, and 3% sulfur. It is lethal to non-native life and the rain is acid.
The two stars orbit a central point, with the planet orbiting both of them in the Goldilocks zone.
It has three moons, of various sizes.
It does have life on it, but is closer to fantasy then sci-fi.
What color is the sky during daylight?