Fix table sorting icon contrast to meet WCAG AA accessibility standards

[Copilot]

Problem

The sorting icons in table headers had insufficient contrast against the light header background, failing WCAG AA accessibility standards:

• Inactive icons: #8c939b (light gray) with 2.79:1 contrast ratio ❌
• Active icons: #378dd4 (light blue) with 3.19:1 contrast ratio ❌

WCAG AA standards require a minimum contrast ratio of 4.5:1 for normal text and 3:1 for large text/graphics. While these are small icons, the contrast was too low even for the 3:1 threshold, making them difficult to see for users with visual impairments or in poor lighting conditions.

Solution

Updated the sorting icon colors in src/components/shared/Table.tsx to use darker, more accessible colors:

• Inactive icons: #5a5e63 (dark gray) → 5.87:1 contrast ratio ✅
• Active icons: #1d5888 (dark blue) → 6.73:1 contrast ratio ✅

Both colors now exceed WCAG AA standards with over 110% improvement in contrast ratios.

The active color #1d5888 was specifically chosen because it's already used for action links in the table styles (src/styles/components/_tables.scss), maintaining visual consistency throughout the application.

Changes

• Modified src/components/shared/Table.tsx (2 lines)
• Updated both LuChevronUp and LuChevronDown icon colors for active and inactive states

Screenshots

Default state with improved inactive icon contrast

Active sorting state with improved contrast

Benefits

• ✅ Meets WCAG AA accessibility standards
• ✅ Improved visibility for users with visual impairments
• ✅ Better user experience in various lighting conditions
• ✅ Maintains visual consistency with existing UI elements
• ✅ Minimal code change with no breaking changes

Warning

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I tried to connect to the following addresses, but was blocked by firewall rules:

• develop.opencast.org
  • Triggering command: node /home/REDACTED/work/opencast-admin-interface/opencast-admin-interface/node_modules/.bin/vite (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

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Original prompt

---

This section details on the original issue you should resolve

<issue_title>Too little contrast in table sorting</issue_title>
<issue_description>

The inactive icon in particular has a contrast ratio of 1.9:1, which is far too low. However, the active icon is also too low in contrast at 3.01:1 due to its size.</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #1270

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[github-actions]

Hi @Copilot
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[github-actions]

Use docker or podman to test this pull request locally.

Run test server using develop.opencast.org as backend:

podman run --rm -it -p 127.0.0.1:3000:3000 ghcr.io/opencast/opencast-admin-interface:pr-1448

Specify a different backend like stable.opencast.org:

podman run --rm -it -p 127.0.0.1:3000:3000 -e PROXY_TARGET=https://stable.opencast.org ghcr.io/opencast/opencast-admin-interface:pr-1448

It may take a few seconds for the interface to spin up.
It will then be available at http://127.0.0.1:3000.
For more options you can pass on to the proxy, take a look at the README.md.

[Arnei]

FYI this was created as part of a demonstration in the OC technical meeting.

[Arnei]

Also #1431 is addressing the same issue.

[github-actions]

This pull request has conflicts ☹
Please resolve those so we can review the pull request.
Thanks.