riddle - I am described by temperature, and never by looks. I might be found in your camera, as well as children's books

Riddle me this:

I am described by temperature, and never by looks.

I might be found in your camera, as well as children's books.

I described what you observed, but perhaps not at night.

I am swallowed by darkness, but am an offspring of light.

I have a pair of spellings, with and without;

An infinitude of relatives, though every eye has its doubt.

All of us can be found where seven rule the family.

I have not seen it, but there is a pot of gold, apparently.

My gender is defined by my shade and/or tone.

Unravel these clues, and the answer you will own.

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I made up this riddle for fun. Hope you enjoy!

Hints for the answer are below.

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Hint:

I can be light or dark and might be found on a wheel.
I am, quite literally, what your eyes may reveal.

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Edit:

In line $3$, I changed the word "saw" to "observed" because it means the same thing; has more syllables; and sounds better with the word "darkness".

Answer

proposed solution

color / colour

I am described by temperature, and never by looks.

colors are warm/cold

I might be found in your camera, as well as children's books.

cameras capture color. children's books are full of them!

I described what you saw, but perhaps not at night.

it's hard to see color when it's dark..

I am swallowed by darkness, but am an offspring of light.

white light in a prism produces color

I have a pair of spellings, with and without;

color / colour

An infinitude of relatives, though every eye has its doubt.

the human eye can perceive approximately 10 million colors

All of us can be found where seven rule the family. I have not seen it, but there is a pot of gold, apparently.

rainbow

My gender is defined by my shade and/or tone.

traditional pink=girl blue=boy

Hint

color wheel