Regex Tester & Validator

Matches SCSS placeholder selectors (abstract classes) such as %button { ... }, capturing the placeholder name and its rule body. The % prefix denotes a Sass placeholder that is omitted from compiled CSS unless used with @extend, making this pattern useful for extracting, auditing, or refactoring placeholder definitions in SCSS codebases (e.g., detecting unused abstract classes). Requires global and dotall flags since the body spans multiple lines.