I'm doing the customization according to this document: http://public.dhe.ibm.com/software/dw/lotus/LC30CustomizeFinal.pdf
I understand how the themes work. The custom.css in deafaultTheme folder affects the defaultTheme, custom.css in goldTheme folder affects the goldTheme. And yes I could wirte everything on the defaultTheme.css. This is not the issue.
The porblem seems to be that: A community page uses it's defaultTheme.css (or goldTheme uses the goldTheme.css, etc.) in addition to theme.css. If you check the stylesheets used on a any other page in connections the list will be: base.css and theme.css. In a community page it will be base.css, "theThemeName".css and theme.css.
Theme.css is constucted from defaultTheme.css and the custom.css. You can see your custom.css code at the end. The code that overwrites the default values above.
However In a community page you get the additional defaultTheme.css. So now my code that overwrites the original gets overwriten by the original from the defaultTheme.css. Does anyone know why the logic is built like this? It doesn't make any sense to me.