Set the reading constraints first
A large portfolio heading needs to remain legible on a small screen and restrained on a wide one. Decide the smallest acceptable size and the largest useful size before choosing a scaling formula. Those boundaries should follow the actual heading and available line length, rather than copying values from a visually different landing page.
Read the three parts of clamp
A declaration such as font-size:clamp(2.25rem, 1.25rem + 4vw, 5rem) has a lower bound, a preferred expression and an upper bound. The middle expression responds to viewport width, while the bounds stop it becoming too small or too large. Keep compatible units and spacing around arithmetic operators when writing the expression.
Include a relative text component
Using only viewport units can make text resizing behave in surprising ways. A preferred value that includes rem ties part of the result to the root font size. That is not a guarantee of accessibility by itself. Test browser zoom and user font settings to confirm the heading can actually enlarge without clipping or overlapping other content.
Design the line breaks as content
A heading like Interfaces that work beautifully may occupy two lines at one width and three at another. Give it an appropriate maximum line length and line height. Avoid inserting a forced line break after every word simply to imitate the desktop composition. A fluid font size cannot rescue a rigid block that refuses to accommodate real text.
Use a small hierarchy of scales
Not every label needs fluid sizing. Reserve the larger scaling range for display headings, use a modest range for section titles, and keep body text comfortably readable. A site with every caption changing size can feel unsettled. Consistent spacing and predictable hierarchy usually matter more than making every value respond continuously.
Verify the endpoints and the middle
Inspect the heading at the minimum width, the maximum width and several widths in between. Replace it with a longer project title and increase the browser’s text size. Check buttons, navigation and adjacent imagery for collisions. Keep a simple fallback font size if supporting environments that do not understand the chosen modern CSS expression.
Further reading
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