Step 4. Reflection
"If it’s interactive it needs a focus style" - Eric Bailey
One of the stereotypes is that the default keyboard focus isn't aesthetic, so it's often removed through CSS. In reality, it can benefit your design as well as your users' navigation. You can style it as you like as long as it is visually apparent.
Please note, WCAG 2.2 is releasing a guideline "2.4: Navigable" on the required focus width and its contrast ratio. Check out the resources for more information.