Visual Focus

It is important to make sure that keyboard-only users can determine where they are in the page when they are using the Tab key to navigate. They can know where they are because when an object receives focus, there is a focus ring around the object.

By default, the browser will always show a focus ring around an object that is keyboard focusable, like a link, or any object which has a value set of 0 or greater for the tabindex attribute. However, it is very popular to override this default browser behavior, often in CSS reset files. It is often accomplished with the following code.

Do not disable the browser’s default outline style for focusable elements

This makes it so elements that can receive the keyboard focus do not have a focus ring around them when the user tabs to it. This makes it very difficult for non-mouse users to know where they are on the page.

  :focus {outline:none;}

The solution is very simple. You simply need to either not override the default browser behavior, or explicitly set a property for the focus

Explicitly set the focus ring style

If you need to correct the issue, you can explicitly set the focus style to make it whatever style you want.

  :focus {outline:2px solid #f00;}

Also, be sure you don’t have any overridden focus rules on objects like links.