consider removing the "share" bar in responsive mode

[ghwood]

URL

https://beta.ietf.org

Expected Behavior

don't block content with the share bar when smaller viewpoints

Actual Behavior

Currently, the share bar blocks a significant fraction of the screen in responsive mode

Reproducing

• Browser:
• OS: [Operating System name] [Version]
• (anything else you think we might need to reproduce this)

[ghwood]

this is done.