Adjust font-sizes slightly to improve readability

[eriknson]

I suggest we reduce our font-sizes down slightly, see sizes and preview below.

• h1 32px
• h2 24px
• h3 18px
• h3 16px

Current design for comparison

[alexandratran]

After testing this out, I think it may be better to leave the heading sizes as they are, because the 16px h3 size would be almost the same as the paragraph font size, and there might be cases (e.g., pages with long lists of complex content, such as API references) where we want to use the h4 heading size - which needs to be at the least the same size as the paragraph font size.

[vandan]

@eriknson we may need further guidance on tuning the font sizes.

[vandan]

Re-opening this issue because we still believe some fine tuning is necessary.

[vandan]

from @eriknson

h3 or definitely h4 should be a similar size as paragraph and differentiated using e.g. font-weight / color. I think we should re-open this issue because right now titles are way to big and negatively affecting the readability. See how e.g. linear sizes their titles for inspo.