The text-emphasis-style property controls the visual form of emphasis marks that are drawn alongside text — the small decorative symbols used to call attention to characters or syllables without changing the underlying text content. It governs how the marks look (their shape and fill) rather than where they appear or what color they use. Emphasis marks are typically associated with East Asian typographic conventions but can be applied to any inline text; they are rendered by the user agent as decorations attached to glyphs rather than as additional characters, so they do not become part of the textual content itself.

When designing with emphasis marks you often need to coordinate the appearance set by text-emphasis-style with complementary properties that control position and color. For position control you can use text-emphasis-position, and for color you can use text-emphasis-color. There is also a shorthand that combines style and color into a single declaration: text-emphasis. Those properties together let you produce emphasis marks that match the document’s writing mode and visual design while keeping the semantic text unchanged.

In practical use, consider readability and contrast: emphasis marks are decorative cues and should remain legible at the sizes and line heights where they’re applied. User agents may substitute or slightly alter shapes depending on font support and writing direction (horizontal vs. vertical), so test in the contexts where your content will be read. Finally, because emphasis marks are treated as separate render-time decorations, they typically do not affect layout flow or text selection, but their appearance can still influence perceived spacing and visual rhythm, so apply them judiciously for clarity rather than ornamentation.