Accessibility

Built to meet WCAG 2.1 Level AA

Why this matters to me

I want this course site to work for every student, including those who navigate by keyboard, use a screen reader, prefer reduced motion, or need to enlarge the text. Accessibility is something I care about personally, and I keep improving it. If anything here doesn't work for you, please tell me (see below) and I'll fix it.

What I've built for accessibility

Keyboard

Every interactive element is reachable and operable by keyboard, in a logical tab order.
The visualizations have keyboard controls: Space to play or pause, arrow keys to step, R to reset.
Visible focus indicators on links, buttons, and controls.

Screen readers

Semantic HTML with a proper heading structure and landmark regions.
ARIA roles and labels on navigation and on every visualization control.
Live regions that announce each step of an animation as it happens.

Visual and reading

A high-contrast color scheme; body and UI text are designed to meet at least a 4.5:1 contrast ratio.
Each visualization includes a text color legend, so meaning never depends on color alone.
The layout reflows and stays usable when text is enlarged up to 200% and across screen sizes.

Motion

Animations are user-initiated (nothing auto-plays) and can be paused or stepped through one operation at a time.
The site honors the prefers-reduced-motion setting.

Standard and testing

This site is built to meet the WCAG 2.1 Level AA success criteria and the principles of Section 508, and is checked with axe DevTools automated testing across its pages. It has not been formally audited or certified by a third party, and accessibility work is ongoing.

Feedback

If you hit an accessibility barrier, please open a GitHub issue or email me. I treat accessibility reports as bugs and prioritize them.

Resources

Last updated: June 29, 2026