code: @Nonnull
    @ReturnsMutableCopy
    public ICommonsList <CSSKeyframesRule> getAllKeyframesRules ()
    {
      return m_aRules.getAllMapped (r -> r instanceof CSSKeyframesRule, r -> (CSSKeyframesRule) r);
    }
docs: Get a list of all top-level rules that are keyframes rules (implementing
  {@link CSSKeyframesRule}).
  
  @return A copy of all contained <code>@keyframes</code> rules. Never
  <code>null</code>.