How to work with character styles
Define a character style
Open the Resource Panel > Brand Kit panel.
Select the last tab (right) to view paragraph- and character styles
Click on the "+" sign to ad a new character style (bottom section is for character styles). Each click on the "+" sign will add another (empty) character style.
Click on the "..." menu next to the newly created style and choose edit or click the pencil to edit the style.
You can rename the style by clicking "Rename" in the "..." menu.
Set all properties you want for this character. Saving happens automatically.
Apply a character style
Select the text you want to apply the character style to.
Different than with paragraph styles, with character styles you need to select the character or words you want to apply the style to.
In the properties panel on the right, select the character style from the dropdown list.
Your selected text now has the character style applied.
Background color
A character style can include a background color — a colored fill that sits behind the characters the style is applied to. This is the typographic equivalent of a text highlight, useful for callouts, badges, labels, and short emphasized runs of text inside a paragraph.
Enable the background color in the character style editor and pick any Brand Kit color (gradients are supported). Once enabled, every text selection that uses the style picks up the background automatically, and the background scales with copyfitting so it stays aligned with the text it follows.