Advanced cross-browser flexbox – Dev.Opera
There are limitations to using flexbox at the moment, and it will be much easier when flexbox is just supported across all modern browsers in the same way. For now, it is much more effective to just stick to simpler, single line uses of flexbox, as multi-line flexboxes can’t really be done effectively in legacy-flex supporting browsers. As it standards, my example works ok, even though the legacy layout is not as good as the modern flexbox layout; one other interesting problem is that Firefox seems to refuse to center content that has been laid out as a flexbox using the margin: 0 auto trick (the centering works fine in Safari).
For simple flexbox uses however, you can get things working well a wide range of modern browsers: Chrome, Firefox, Safari, Opera Presto 12.1+, IE 10+, iOS and Android.