docs(style[toc,body]): refine right-panel TOC and body typography

tony · tony · commit 2b483f3708e6 · 2026-03-12T17:15:22.000-06:00
why: Furo's default TOC title (10px) is nearly invisible and smaller
than its own items (12px), inverting typographic hierarchy. Body
line-height (1.5) is tighter than WCAG-recommended range.
what:
- Bump TOC item size 75% → 81.25% (12→13px) via --toc-font-size
- Bump TOC title size 62.5% → 87.5% (10→14px) via --toc-title-font-size
- Increase .toc-tree line-height 1.3 → 1.4 for wrapped entries
- Increase article line-height 1.5 → 1.6 for paragraph readability
- Enable text-rendering: optimizeLegibility on body
diff --git a/docs/_static/css/custom.css b/docs/_static/css/custom.css
@@ -83,3 +83,33 @@ article h6 {
   font-size: 1em;
   margin-top: 1rem;
 }
+
+/* ── Right-panel TOC refinements ────────────────────────────
+ * Adjust Furo's table-of-contents proportions for better
+ * readability. Inspired by Starlight defaults (Biome docs).
+ * Uses Furo CSS variable overrides where possible.
+ * ────────────────────────────────────────────────────────── */
+
+/* TOC font sizes: items 75% → 81.25% (12→13px),
+   title 62.5% → 87.5% (10→14px) */
+:root {
+  --toc-font-size: var(--font-size--small--2);
+  --toc-title-font-size: var(--font-size--small);
+}
+
+/* More generous line-height for wrapped TOC entries */
+.toc-tree {
+  line-height: 1.4;
+}
+
+/* ── Body typography refinements ────────────────────────────
+ * Improve paragraph readability with wider line-height and
+ * sharper text rendering. Furo already sets font-smoothing.
+ * ────────────────────────────────────────────────────────── */
+body {
+  text-rendering: optimizeLegibility;
+}
+
+article {
+  line-height: 1.6;
+}
