Share button auto resizing

Hi,

this plugin looks like it is exactly what I could use to protect the privacy of my users. Thank you so much for making it available.

On your test site in theme twenty eleven, the buttons automatically resize when I reduce the screen width. (Firefox latest version, Windows 10)

On my test blog with the same theme, twenty eleven, where I have installed the plugin, the buttons break into the next line instead of resizing when I reduce the screen width.
I use the default buttons, size medium.
Unfortunately my test blog is a staging site and hence password protected.

How can I get the same behavior as you on your test site?

Thank you very much for taking the time.

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