Describe the bug
In meta decidim when I try to do an action that require to be signed in a pop-up is displayed. In this one I can sign in with my ids or with Auth. There is a bug with the button sign in with Decidim, the text is not shown.

To Reproduce
Steps to reproduce the behavior:

1. Go to meta.decidim (don't sign in)
2. Try to follow a proposition
3. See the pop-up
4. See an red red button

Expected behavior
The text " sign in with Decidim" should be displayed.

Screenshots
If applicable, add screenshots to help explain your problem.

Extra data (please complete the following information):

• Device: all
• Device OS: all
• Browser: all
• Decidim Version: 0.25