This property is a shorthand for rest-before and rest-after. If two values are given then the first value is rest-before and the second is rest-after.
Values for "rest"
|CSS Speech Level 1||"<'rest-before'> <'rest-after'>?"|
- In contrast to the pause properties, a rest is inserted between an element's content and any "cue-before" or "cue-after" content. Adjacent rests are treated additively.
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