The follow-up to PR #1514. That PR tightened the shared partial's values; this PR removes the duplicates so there's actually one place to edit going forward.
Before: five places defined .sidebar-navigation .sidebar-item a — the shared partial + four per-site copies, each keyed off a different accent variable (`$accent`, `$kits-accent`, `$colabs-accent`, `$mlsysim-accent`). Plus a 1350-line orphan `book/quarto/assets/styles/style.scss` that was referenced nowhere and carried yet another copy.
After: every site imports the shared partial once. Each site aliases `$accent` to its own site-accent (book via `themes/_theme-harvard`, kits/labs/mlsysim at line 19 of their `style.scss`), so the partial's accent-keyed hover/active states resolve to the right color per site without needing per-site rule copies.
Net −1508 lines, zero behavior change — the partial was already tightened to match these exact values in PR #1514, so removing the duplicates does nothing visible.
Orphan file deletion
`book/quarto/assets/styles/style.scss` was orphaned — the book's builds consume `style-vol1.scss` and `style-vol2.scss` (referenced in `book/quarto/config/_quarto-html-vol1.yml` line 175 and `_quarto-html-vol2.yml` line 178). I checked every `.yml`, `Makefile`, `.sh`, `.py`, `.js`, and `*.scss` file for references to `style.scss` — zero hits. Safe to delete. If something obscure turns up needing it, restore from `git show HEAD^:book/quarto/assets/styles/style.scss`.
Kept per-site
Two site-specific sidebar extras stay in their respective files because they're genuinely site-specific, not duplicated shape:
kits: `.sidebar-title` (teal underline styling) — not part of the shared partial's concerns
mlsysim: faint dividers between top-level sidebar sections — a visual choice only mlsysim wants
These are additive — they style different things from the shared rules.
Untouched
tinytorch: already imported the partial directly (was the site the whole redesign started from)
site (landing): imports the partial via `shared/styles/_ecosystem-base.scss`
slides, instructors: no sidebar rules before, no sidebar rules now
Test plan
Grep confirms the only `.sidebar-navigation .sidebar-item a` rule block in active SCSS is the shared partial
Grep confirms every Quarto site with a sidebar imports the partial
Pre-commit hooks pass
Post-merge: preview deploys on each site to confirm sidebars still render correctly (they should — same rules, same accent resolution, just via import instead of copy)
🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.
## 📋 Pull Request Information
**Original PR:** https://github.com/harvard-edge/cs249r_book/pull/1515
**Author:** [@profvjreddi](https://github.com/profvjreddi)
**Created:** 4/24/2026
**Status:** ✅ Merged
**Merged:** 4/24/2026
**Merged by:** [@profvjreddi](https://github.com/profvjreddi)
**Base:** `dev` ← **Head:** `refactor/sidebar-single-source-of-truth`
---
### 📝 Commits (1)
- [`4c33d66`](https://github.com/harvard-edge/cs249r_book/commit/4c33d66200e5f9e6397ca055c5ec6b0f95c58166) refactor(sidebar): consolidate to single source of truth
### 📊 Changes
**5 files changed** (+23 additions, -1531 deletions)
<details>
<summary>View changed files</summary>
📝 `book/quarto/assets/styles/_base-styles.scss` (+7 -59)
➖ `book/quarto/assets/styles/style.scss` (+0 -1351)
📝 `kits/assets/styles/style.scss` (+6 -41)
📝 `labs/assets/styles/style.scss` (+5 -40)
📝 `mlsysim/docs/styles/style.scss` (+5 -40)
</details>
### 📄 Description
## Summary
The follow-up to PR #1514. That PR tightened the shared partial's values; this PR removes the duplicates so there's actually one place to edit going forward.
**Before**: five places defined `.sidebar-navigation .sidebar-item a` — the shared partial + four per-site copies, each keyed off a different accent variable (\`\$accent\`, \`\$kits-accent\`, \`\$colabs-accent\`, \`\$mlsysim-accent\`). Plus a 1350-line orphan \`book/quarto/assets/styles/style.scss\` that was referenced nowhere and carried yet another copy.
**After**: every site imports the shared partial once. Each site aliases \`\$accent\` to its own site-accent (book via \`themes/_theme-harvard\`, kits/labs/mlsysim at line 19 of their \`style.scss\`), so the partial's accent-keyed hover/active states resolve to the right color per site without needing per-site rule copies.
## Diff stat
```
book/quarto/assets/styles/_base-styles.scss | 66 +-
book/quarto/assets/styles/style.scss | 1351 ---------------------------
kits/assets/styles/style.scss | 47 +-
labs/assets/styles/style.scss | 45 +-
mlsysim/docs/styles/style.scss | 45 +-
5 files changed, 23 insertions(+), 1531 deletions(-)
```
**Net −1508 lines**, zero behavior change — the partial was already tightened to match these exact values in PR #1514, so removing the duplicates does nothing visible.
## Orphan file deletion
\`book/quarto/assets/styles/style.scss\` was orphaned — the book's builds consume \`style-vol1.scss\` and \`style-vol2.scss\` (referenced in \`book/quarto/config/_quarto-html-vol1.yml\` line 175 and \`_quarto-html-vol2.yml\` line 178). I checked every \`*.yml\`, \`Makefile\`, \`*.sh\`, \`*.py\`, \`*.js\`, and \`*.scss\` file for references to \`style.scss\` — zero hits. Safe to delete. If something obscure turns up needing it, restore from \`git show HEAD^:book/quarto/assets/styles/style.scss\`.
## Kept per-site
Two site-specific sidebar extras stay in their respective files because they're genuinely site-specific, not duplicated shape:
- **kits**: \`.sidebar-title\` (teal underline styling) — not part of the shared partial's concerns
- **mlsysim**: faint dividers between top-level sidebar sections — a visual choice only mlsysim wants
These are additive — they style different things from the shared rules.
## Untouched
- **tinytorch**: already imported the partial directly (was the site the whole redesign started from)
- **site (landing)**: imports the partial via \`shared/styles/_ecosystem-base.scss\`
- **slides, instructors**: no sidebar rules before, no sidebar rules now
## Test plan
- [x] Grep confirms the only \`.sidebar-navigation .sidebar-item a\` rule block in active SCSS is the shared partial
- [x] Grep confirms every Quarto site with a sidebar imports the partial
- [x] Pre-commit hooks pass
- [ ] Post-merge: preview deploys on each site to confirm sidebars still render correctly (they should — same rules, same accent resolution, just via import instead of copy)
---
<sub>🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.</sub>
Blocking a user prevents them from interacting with repositories, such as opening or commenting on pull requests or issues. Learn more about blocking a user.
📋 Pull Request Information
Original PR: https://github.com/harvard-edge/cs249r_book/pull/1515
Author: @profvjreddi
Created: 4/24/2026
Status: ✅ Merged
Merged: 4/24/2026
Merged by: @profvjreddi
Base:
dev← Head:refactor/sidebar-single-source-of-truth📝 Commits (1)
4c33d66refactor(sidebar): consolidate to single source of truth📊 Changes
5 files changed (+23 additions, -1531 deletions)
View changed files
📝
book/quarto/assets/styles/_base-styles.scss(+7 -59)➖
book/quarto/assets/styles/style.scss(+0 -1351)📝
kits/assets/styles/style.scss(+6 -41)📝
labs/assets/styles/style.scss(+5 -40)📝
mlsysim/docs/styles/style.scss(+5 -40)📄 Description
Summary
The follow-up to PR #1514. That PR tightened the shared partial's values; this PR removes the duplicates so there's actually one place to edit going forward.
Before: five places defined
.sidebar-navigation .sidebar-item a— the shared partial + four per-site copies, each keyed off a different accent variable (`$accent`, `$kits-accent`, `$colabs-accent`, `$mlsysim-accent`). Plus a 1350-line orphan `book/quarto/assets/styles/style.scss` that was referenced nowhere and carried yet another copy.After: every site imports the shared partial once. Each site aliases `$accent` to its own site-accent (book via `themes/_theme-harvard`, kits/labs/mlsysim at line 19 of their `style.scss`), so the partial's accent-keyed hover/active states resolve to the right color per site without needing per-site rule copies.
Diff stat
Net −1508 lines, zero behavior change — the partial was already tightened to match these exact values in PR #1514, so removing the duplicates does nothing visible.
Orphan file deletion
`book/quarto/assets/styles/style.scss` was orphaned — the book's builds consume `style-vol1.scss` and `style-vol2.scss` (referenced in `book/quarto/config/_quarto-html-vol1.yml` line 175 and `_quarto-html-vol2.yml` line 178). I checked every `.yml`, `Makefile`, `.sh`, `.py`, `.js`, and `*.scss` file for references to `style.scss` — zero hits. Safe to delete. If something obscure turns up needing it, restore from `git show HEAD^:book/quarto/assets/styles/style.scss`.
Kept per-site
Two site-specific sidebar extras stay in their respective files because they're genuinely site-specific, not duplicated shape:
These are additive — they style different things from the shared rules.
Untouched
Test plan
🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.