Let's see here...
You can go into the topic.less file in the lavender template. It should be located node_modules/nodebb-theme-lavender/less/topic.less.
Look for .post-content it should be in the following hierarchy: .topic .posts .post-content. Example below:
//You can put whatever font-size here.
Hope this helps!
On lavender theme this is .topic-text if it is not a change in css since then.
@baris for blockquote :
I made a try but it doesn't work. Any update on this or is it Lavender theme related ?
That's a very good write up Steve, you should be in marketing if your not already
LOL I have been for 15+ years now. Mostly corporate/tech companies helping roll out products/services/promotions. Always liked getting involved with the design so I learned photoshop, illustrator, indesign, etc. along the way. Now i'm working out of my house freelancing.
oh cool haha. meanwhile all three of us are out-and-out programmers with no idea on how to market anything
Been down that road before. Just like programming, marketing is a process. When you guys get to that point of wanting help the 4 of us can all jump on a call and see where it goes.