#666A6D Hex Color

Yes. White text on #666a6d reaches about 5.5:1 contrast, which clears the WCAG AA requirement of 4.5:1 for body text. Dark text will not pass, so reserve this shade for backgrounds under light type.

Warm accents like burgundy or mustard offset its cool undertone and keep palettes from feeling flat. For a quieter scheme, layer it with navy and off-white in a 60/30/10 split.