Fluid typography calculator

Produces a `clamp()` that scales a font size linearly between two viewport widths and stops at both ends — the modern replacement for a stack of font-size media queries.

The output uses rem rather than px for the minimum and maximum deliberately. A clamp expressed entirely in px ignores the user’s browser font-size setting, which means someone who has increased it for readability gets no benefit — an accessibility failure that is easy to ship without noticing. Mixing a rem intercept with a vw slope keeps the size responsive to both the viewport and the user’s preference. One thing to watch: a very steep slope makes text jump noticeably as a window is resized, so keeping the size difference modest across a wide viewport range usually reads better than a dramatic one.