You are right. I was fixed enabling Custom SMTP and set port 25 and all parameters there:
Where did you put it? It seems to work fine for me when I put it in custom css in ACP.
Make sure custom css is enabled as well.
#red is not a color (just
red is), but other than that I can assure you there is nothing wrong with this CSS and the problem lies elsewhere:
With the original transparent color: