Trying to go from the tablet version to mobile. My thought was that I needed to switch the Flex from Horizontal to Vertical (which has worked for me before). It is not working this time. Instead, the icons are disappearing and the divs are super skinny with I try to realign.
Your read-only link or even your published link would help a lot …
It looks like you could have set fixed widths to your flex items. Just remove them or set it to 100%.