Algebridge Directory

Accessibility

Last updated 13 August 2026

Students who need assistive technology are exactly the students least well served by most maths sites. This page states what has been done and, more usefully, what has not.

Target

We aim to meet WCAG 2.1 Level AA. We do not claim full conformance, because that claim should follow a formal audit and none has been carried out yet.

What is in place

  • Semantic HTML throughout — real headings in order, lists, and a single main landmark per page.
  • A “skip to content” link as the first focusable element on every page.
  • Full keyboard operation. Every control, filter, tab and button is reachable and operable without a mouse, and focus is visible.
  • Body text at 16px with a 1.6 line height, and no maximum-scale restriction, so browser zoom to 200% works normally.
  • Text and background colours chosen to meet the 4.5:1 contrast ratio for body text.
  • Descriptive link text rather than “click here”, and buttons labelled with the topic they act on.
  • Decorative images marked as such so screen readers skip them; video thumbnails carry the topic name via their link.
  • Explanation tabs use ARIA tab semantics with correct selected states.
  • Every topic is complete as text. The video is a supplement, never the only source of an explanation — this matters for deaf and hard-of-hearing students and for anyone on a slow connection.
  • The site works with JavaScript disabled: all content, navigation and topic pages render. Only search, filtering and the saved list require JavaScript.
  • No autoplay, no motion-triggered animation, and no content that flashes.

Known gaps

  • Captions on videos. We embed third-party videos and cannot add captions to them. Most videos from the channels used carry captions, but we do not currently verify this per video, and we do not filter out those without. This is the most significant open gap.
  • Mathematical notation. Expressions are written with Unicode characters rather than MathML. This reads acceptably in most screen readers but is less precise than proper mathematical markup, and some symbols may be announced awkwardly.
  • No formal audit. Nothing here has been tested by an accessibility professional or against a full assistive-technology matrix.
  • No dark mode yet.

Telling us about a problem

If something on the Directory is unusable for you, please say so through the Contact page. Describe the page and what happened. Accessibility reports are treated as bugs, not as feature requests, and are prioritised accordingly.