UnitwiseCompare

Building

Accessibility

This is a tool used one-handed, standing up, often in poor light. Making it work for people using a screen reader, a keyboard or a magnified display is the same work as making it work in an aisle.

In effect from 2026-09-09

The standard we build to

Web Content Accessibility Guidelines 2.1, level AA. It is a check that runs during the build rather than an audit done afterwards, and the build fails if a measured value drifts.

What is measured, not asserted

  • Contrast. Every colour used for text is measured against the page background and the ratio is recorded in the stylesheet. Body text is 4.66 : 1 or better; the main text colour is 15.86 : 1. Two of the eight colours do not reach 4.5 : 1 and so are never used for body text — they carry bars, ticks and rules only, where the 3 : 1 non-text threshold applies. A script recomputes all of this and fails the build on a mismatch.
  • Colour is never the only cue. The lowest unit price, the other sizes, a promotional price and a caveat each have a distinct fill pattern as well as a distinct tone, and each is labelled in words.
  • Every comparison has a plain-text equivalent. The bars are decorative in the strict sense: the same figures, the normalised price for each size and the arithmetic behind it, are written out below the chart in ordinary sentences.
  • The unit switcher is a radio group, so it is reachable by tab and operable with arrow keys, and the change of answer is announced to a screen reader.
  • Every image carries alt text, and no point on this site is made by an image alone.
  • Focus is always visible, with a two-pixel outline and clear offset. There is a skip link to the main content.
  • Reduced motion is respected. If your system asks for less motion, transitions are switched off.
  • Text can be resized to 200% without loss of content, and the layout reflows to a single column.
  • Targets are large. The primary navigation is a fixed bar at the bottom of the screen, within reach of a thumb.

Known limitations

  • Reading a photograph of a shelf label depends on the photograph. If taking one is difficult, every figure can be typed in instead, and typing is a fully supported route rather than a fallback.
  • The comparison card is an image when saved. The same content is always available as text on the page, and can be copied.

If something does not work for you

Email support@heathhallstore.shop and say what you were trying to do and what got in the way. We reply within one working day and always within five. If we cannot fix it quickly we will tell you what we are doing instead in the meantime.

General questions about the service are on the support page.