Notice how God said “let there be light”, he didn’t say “let there be electromagnetic radiation.”
In science light is electromagnetic radiation, but what does the bible say about light?
Perhaps light(s) represents daytime, brightness, illumination, and exposure to truth.
And God said “Let there be light,” and there was light. God saw the light was good and separated the light from darkness. Gen 1:3-4
You, O LORD, keep my lamp burning, my God turns my darkness into light. Psalm 18:28
“You are the light of the world. A city on a hill cannot be hidden. Neither do people light a lamp and put it under a bowl. Instead they put it on its stand, and it gives light to everyone in the house. In the same way, let your light shine before men, that they may see your good deeds and praise your Father in heaven.” Matt 5:14-16
In him was life, and that life was the light of men. The light shines in the darkness, but the darkness has not understood it. John 1:4-5