Page structure is implemented with HTML. Visual appearance is implemented with CSS. Meaningful HTML is not used to solely achieve a visual effect or appearance.
Ensure that each section of the webpage that is visually identified as a landmark region is implemented as a landmark region.
Ensure that HTML does not include any presentational attributes in situations where it is deprecated (e.g., height and width are deprecated on tables). You can utilize the Siteimprove policy "HTML used for presentation instead of CSS" to check.
Ensure that underlining is not used for text emphasis. Underlined text is used to identify a link or other form of interactive text.