themes-wordpress/blank-canvas/inc/wpcom-colors.php

<?php
require_once __DIR__ . '/wpcom-colors-utils.php';

seedlet_define_color_annotations(
	array(
		'background' => '#FFFFFF',
		'foreground' => '#444444',
		'primary'    => '#000000',
		'secondary'  => '#007CBA',
		'tertiary'   => '#FAFAFA',
	)
);