Reference from EEOC
The law forbids discrimination when it comes to any aspect of employment, including hiring, firing, pay, job assignments, promotions, layoff, training, fringe benefits, and any other term or condition of employment.
It is unlawful to harass a person because of that person's race or color.
Harassment can include, for example, racial slurs, offensive or derogatory remarks about a person's race or color, or the display of racially-offensive symbols. Although the law doesn't prohibit simple teasing, offhand comments, or isolatedincidents that are not very serious, harassment is illegal when it is so frequent or severe that it creates a hostile or offensive work environment or when it results in an adverse employment decision (such as the victim being fired or demoted).
The harasser can be the victim's supervisor, a supervisor in another area, a co-worker, or someone who is not an employee of the employer, such as a client or customer.