Global Leader of Cybersecurity Solutions and Services | Fortinet

What is Secure SD-WAN (Software-Defined Wide Area Network)? | Fortinet

Líder global en soluciones y servicios Ciberseguridad | Fortinet

Líder global de soluções e serviços de cibersegurança | Fortinet

사이버 보안 솔루션 및 서비스의 글로벌 리더 | 포티넷

Ethernet Switches - Commercial & Enterprise Ethernet Solutions

サイバーセキュリティのグローバルリーダー | フォーティネット

网络安全解决方案和服务的全球领导者 | Fortinet

網路安全解決方案和服務的全球領導者 | Fortinet

All controls on the page - including links, buttons, and fields - should clearly 
indicate when they have been selected by the keyboard.

All controls on the page - including links, buttons, and fields - should clearly 
indicate when they have been selected by the keyboard.

This is a stricter version of [WCAG 2.4.7](https://www.w3.org/WAI/WCAG21/Understanding/focus-visible.html),
which requires that the focus indicator is visible, but doesn't specify how clearly
it should be visible.

You can confirm this yourself by loading a webpage and using the Tab key to navigate 
through it. Anything you can select should clearly alter its appearance when selected. 
For example, a text field might change color, or have a distinctive border applied. 

## The requirements

The [official requirements](https://w3c.github.io/wcag/understanding/focus-appearance.html) are 
complicated. A simplified version is:

* Surround the control with a solid outline
* The outline must have at least 3:1 contrast with its background
* The outline must have at least 3:1 contrast with its surroundings, or be at least 2px thick

The actual requirements allow for more variation, but generally require that you 
calculate the perimeter and/or area of the focus area, which can be very difficult.

## How to fix

Links and form controls should use a focus selector which contrasts with their
unfocused state, as well as any surroundings of the focus state. 

In practice, the easiest way to accomplish this is to use a two-color focus, like so:

```css
/* ensure high-contrast mode still has an indicator */
outline: 2px transparent solid;

/* Apply a thick yellow box-shadow with 
   a thin dark blue indicator in the middle */
box-shadow: 0 0 0 2px #F9F9D1, 0 0 0 4px #396196, 0 0 4px 8px #F9F9D1;
``` 

From [Technique C40](https://www.w3.org/WAI/WCAG22/Techniques/css/C40).

Using two contrasting colors guarantees that the focus state will be visible, 
regardless of the background or surrounding colors.

## Troubleshooting

### Not enough contrasting pixels change

The [Success Criterion](https://w3c.github.io/wcag/understanding/focus-appearance.html) specifies a minimum area 
for the contrasting portion of the focus indicator, which is equivalent to a 2 CSS pixel border around the component.

From the requirements:

> "The easiest and most common way to meet this requirement is to use a solid outline around the component. 
> The outline must be at least 2px thick."

In practice, many websites use alternatives to this, such as a thick border along one edge. A problem with 
that approach is it is often dependent upon the length of that one edge, which for text links can vary dynamically.

See [Sara Soueidan](https://www.sarasoueidan.com/blog/focus-indicators/#2.-minimum-contrasting-area) for a good
write-up of this concept.

To comply with this Success Criterion, we recommend adding a 2px border around all edges.

Note an earlier draft of this Success Criterion has a more generous allowance here, which is not the case for the
final version.

### Elements appear to change in the browser

Focus states should be defined in CSS alone, and not require JavaScript to work. 

Try disabling JavaScript on the page, and see if focus is still visible. If it not, 
then the focus state won't work with assistive technologies that don't have a physical
keyboard, e.g. mobile phones.

Some more unusual means of implementing a focus state cannot be detected or measured
automatically. These include:

* Focus implemented via pseudo-elements - such as `::after` or `::before`. 
* Focus using `:focus-within` (JavaScript current provides no way to access these).
* Focus cascaded to child elements, e.g. a `<span>` inside an `<a>` tag. We detect
  some of these cases, but there are variations that we cannot detect.

Currently, there is no practical way to assess these focus states automatically.

### Elements over images not analyzed

Silktide cannot assess the contrast of elements that are over images. This is because
the contrast of an element is calculated by comparing the color of the element with the
color of the background. 

If the element is over an image, the background color is the
color of the image, which varies from pixel-to-pixel, and may vary further as the page
is resized, due to responsive design.

### Unexpected elements are focusable

You may be surprised to see tags like `<div>` or `<span>` being shown as focusable.
If an element has a `tabindex` of 0 or higher, it becomes focusable. Any HTML tag can be made 
focusable in this way, this is so that custom controls (e.g. your own drop-down menus, or 
sliders) can support keyboard navigation. [Learn more about tabindex on MDN](https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/tabindex).

## Further reading

* [WCAG 2.4.13](https://www.w3.org/WAI/WCAG22/Understanding/focus-appearance.html)
* [Minimum Contrasting Area explained (Sara Soueidan)](https://www.sarasoueidan.com/blog/focus-indicators/#2.-minimum-contrasting-area)

ensure-focus-appearance

August 2025

July 2025

Fortinet

Title / URL	Issues
Global Leader of Cybersecurity Solutions and Services \| Fortinetwww.fortinet.com/	100
What is Secure SD-WAN (Software-Defined Wide Area Network)? \| Fortinetwww.fortinet.com/products/sd-wan	93
Líder global en soluciones y servicios Ciberseguridad \| Fortinetwww.fortinet.com/lat	91
Líder global de soluções e serviços de cibersegurança \| Fortinetwww.fortinet.com/br	91
Global Leader of Cybersecurity Solutions and Services \| Fortinetwww.fortinet.com/uk	91
사이버 보안 솔루션 및 서비스의 글로벌 리더 \| 포티넷www.fortinet.com/kr	91
Ethernet Switches - Commercial & Enterprise Ethernet Solutionswww.fortinet.com/products/ethernet-switches	84
サイバーセキュリティのグローバルリーダー \| フォーティネットwww.fortinet.com/jp	80
网络安全解决方案和服务的全球领导者 \| Fortinetwww.fortinet.com/cn	80
網路安全解決方案和服務的全球領導者 \| Fortinetwww.fortinet.com/tw	79

Ensure controls clearly indicate when they are selected

Fortinet

Where this issue has occurred