Nesting two loops - red in all lights

gistfile1.txt

import time
import board
import neopixel

pixel_pin = board.D2
num_pixels = 16

pixels = neopixel.NeoPixel(pixel_pin, num_pixels, brightness=0.7, auto_write=False)

while True:
    for red_fade_value in range(0, 254, 2):   #fade in loop
        color = (red_fade_value, 255, 25)
        for light_index in range (0, 16, 1):
            pixels[light_index] = color
        pixels.show()

    for red_fade_value in range(254d, 0, -2):   #fade out loop
        color = (red_fade_value, 25, 255)
        for light_index in range(0, 16, 1):
            pixels[light_index] = color
        pixels.show()