The only thing the flag code says about the design of the flag itself is below. Everything else is about how the flag should be treated, used, and displayed:
"§1. Flag; stripes and stars on
The flag of the United States shall be thirteen horizontal stripes, alternate red and white; and the union of the flag shall be fifty stars representing the fifty states, white in a blue field
§2. Same; additional stars
On the admission of a new State into the Union one star shall be added to the union of the flag; and such addition shall take effect on the fourth day of July then next succeeding such admission"
I know that France recently altered the shade of blue that they use to be a darker one on their flag, so there is probably some variability in a number of countries.
The only thing the flag code says about the design of the flag itself is below. Everything else is about how the flag should be treated, used, and displayed:
"§1. Flag; stripes and stars on
The flag of the United States shall be thirteen horizontal stripes, alternate red and white; and the union of the flag shall be fifty stars representing the fifty states, white in a blue field
§2. Same; additional stars
On the admission of a new State into the Union one star shall be added to the union of the flag; and such addition shall take effect on the fourth day of July then next succeeding such admission"
This is shockingly generic.
It also doesn’t specify shades of colors involved, number of points on the stars, arrangements of stars, or size of the canton.
That being said, according to WP, it looks like the US government does use standards for colors; just doesn’t expect others to do the same:
https://en.wikipedia.org/wiki/Flag_of_the_United_States#Design
I know that France recently altered the shade of blue that they use to be a darker one on their flag, so there is probably some variability in a number of countries.
It doesn’t even say that the blue field must be in the top right