code: func (p *PathSpec) GetRelativeThemeDir() string {
  	if p.ThemeSet() {
  		return strings.TrimPrefix(filepath.Join(p.ThemesDir, p.Themes()[0]), FilePathSeparator)
  	}
  	return ""
  }
docs: // GetRelativeThemeDir gets the relative root directory of the current theme, if there is one.
  // If there is no theme, returns the empty string.