Shea Sullivan Two-Toned Blonde

Any colorist will tell you, it is imperative to match existing hair tones when it comes time to cover regrowth.  One would take care not to allow the new color to be darker than what exists, and certainly not alllow a color line to develop.  While the latter still applies, two tones are no longer a thing to avoid, yet rather a trend to adhere to as this look on Shea Sullivan will confirm.