code: function getKeyframesSelectorsGroup() {
    let selectorsGroup = [];
    const selectorsGroupEnd = tokens[pos].selectorsGroupEnd;
  
    selectorsGroup.push(getKeyframesSelector());
  
    if (checkSC(pos) && tokens[pos].type !== TokenType.Newline) {
      selectorsGroup = selectorsGroup.concat(getSC());
    }
  
    while (pos < selectorsGroupEnd) {
      selectorsGroup = selectorsGroup.concat(
        getDelim(),
        getSC(),
        getSC(),
        getSC(),
        getKeyframesSelector()
      );
  
      if (checkSC(pos) && tokens[pos].type !== TokenType.Newline) {
        selectorsGroup = selectorsGroup.concat(getSC());
      }
    }
  
    return selectorsGroup;
  }
docs: Get the keyframe's selector groups
  @return {Array} An array of keyframe selectors