Geist Mono as a heading font

Key CSS for monospace fonts at display sizes: letter-spacing: -0.03em and word-spacing: -0.05em. Without this, monospace headings look loose and gappy because the characters are all the same width — wide letters like m and w don’t compensate for narrow ones like i and l.

Geist Mono handles this better than most because it was designed for UI contexts, not just code.