Keyboard navigation impossible
Keyboard accessibility is one of the most important aspects of web accessibility. There are a whole host of reasons why certain users will find mouse usage difficult or impossible. Some users may have no use or limited use of their hands or arms and rely on the keyboard or alternative input devices to navigate websites. Blind people using screen reading software almost exclusively rely on keyboard navigation.
Recently, in my role of auditing websites for accessibility, I have come across a number of websites that make keyboard navigation impossible, because critical sign-posting allowing users to see where they are on the page are missing.
When keyboard users navigate websites, they jump from link to link using the tab key. They can see where they are on the page because the link with the focus has a dotted border around it. These borders should be visible by default, like they are on the BBC website but on a number of websites I have visited, they have been removed. Maybe the web designer considered them ‘ugly’ and removed them (this can be done by setting the physical appearance of the ‘outline-style’ property to ‘none’) because they spoilt his or her design of the page, not realising the huge impact this has on users with disabilities.
Dotted borders on the BBC website appear
around links that have the current keyboard focus.
The simplest way to ensure that a visual indicator is present is to do nothing and let the dotted borders appear by default. However, these dotted borders are not always easy to see, especially if background colours are being used. To make them obvious, CSS techniques can be used to display a different background colour when the link receives the focus. This is a great technique and can be seen in action on the Easy Slideshare website.
Links with the current keyboard focus can be made
more obvious by adding a different background colour.
A clear and distinct visual indicator is essential for sighted users that rely on keyboard navigation. Without them, websites become impossible to use as users are not able to see where they are on a page.