希望有简单的引导程序问题：引导程序列在safari桌面上怪异地堆叠？

Question

所以我已经使用引导程序一段时间了，我有一个非常简单的网格设置，可以在Chrome / Firefox上正常运行，但是在Safari中的堆栈不正确：

这是标记，我真的看不出有什么问题！如果您正在查看包含div的任何内容，也可以在www.inspiringtravelcompany.co.uk上实时查看。

 <div class="w-100 pb-5" style="background-color:#f7f7f7">
        <div class="container">
            <div class="row">
                <div class="col-12 col-md-6 order-2 order-md-1">
                    <p class="fs-20 mb-2 ChronicleDeckSemiBold" style="line-height:1.3;">
                        You may have seen us recently during your favourite television programmes – and if not we’d love to share our brand new video with you.
                    </p>
                    <p class="fs-14 mb-2 ChronicleDeck">
                        Take a look, and you’ll spot some of our most popular destinations and favourite bucket list spots around the world.
                    </p>
                    <p class="fs-14 mb-2 ChronicleDeck">
                        Here at the Inspiring Travel Company we specialise in bespoke, personalised and tailor-made holidays around the world to the most amazing places; so whether you’re after a relaxing ‘fly and flop’ break or an intrepid tour, a bucket list safari or a trip to catch the world’s premier sporting events, our Travel Specialists are ready and waiting to offer first-hand insight.
                    </p>
                </div>
                <div class="col-12 col-md-6 order-1 order-md-2 mb-4 mb-md-0">
                    <iframe class="w-100" width="640" height="385" src="https://www.youtube.com/embed/x5sqxiO_muk">
                    </iframe>
                </div>
            </div>
        </div>
    </div>

我就是不明白问题是什么！