Configure outline, outline-offset, and focus-visible styles with accessibility-friendly defaults.
CSS Outline Generator assembles an outline's width, style, color, and offset into a reusable focus rule, with a :focus-visible option for showing the treatment when browser focus heuristics call for it. It is suited to designing keyboard focus indicators without changing an element's dimensions. The common mistake is treating outline like border: an outline occupies no layout space, and outline-offset changes only where the ring is painted, not the box size or available spacing around it.
Width, line style, and color define the outline. Offset is represented separately by outline-offset because it is not part of the outline shorthand. Positive offsets move the outline away from the border edge, while negative offsets move it inward. The outline is visual only: it does not enlarge the CSS box or alter surrounding layout.
The focus-visible option scopes the chosen treatment to elements matching :focus-visible. This pseudo-class requires focus and leaves indicator matching to browser heuristics; it is not simply a synonym for keyboard focus. Input method, element type, and context can influence whether the selector matches, so its behavior should be tested through actual keyboard and pointer interaction.
No. A positive outline-offset moves the outline outward visually, but the browser does not reserve that distance in layout. If the ring collides with neighboring content, increase actual component spacing separately. A negative value moves the outline toward the element and can place the ring over its border or interior.
No. The pseudo-class is based on user-agent heuristics, and input modality is only one factor. A browser may show it for an element that needs keyboard input, such as a text field, even after pointer interaction. Treat it as a focus-indication policy, not as a reliable keyboard-user detector.
The behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.
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