diff --git a/html/styles/custom.css b/html/styles/custom.css
index dffbc41b..44e8b841 100644
--- a/html/styles/custom.css
+++ b/html/styles/custom.css
@@ -612,6 +612,18 @@ textarea:focus-visible {
   outline-offset: 2px;
 }
 
+/* Links inside running text are underlined, so they do not rely on color
+   alone (WCAG 1.4.1; axe link-in-text-block, community-access.github.io#6).
+   github-markdown-css underlines them only on hover. */
+.markdown-body p a,
+.markdown-body li a,
+.markdown-body td a,
+.markdown-body blockquote a,
+.markdown-body dd a {
+  text-decoration: underline;
+  text-underline-offset: 2px;
+}
+
 /* High contrast mode support */
 @media (prefers-contrast: high) {
   body {
diff --git a/scripts/build-html.js b/scripts/build-html.js
index 7b383a9b..961c9e8b 100644
--- a/scripts/build-html.js
+++ b/scripts/build-html.js
@@ -1607,6 +1607,18 @@ textarea:focus-visible {
   outline-offset: 2px;
 }
 
+/* Links inside running text are underlined, so they do not rely on color
+   alone (WCAG 1.4.1; axe link-in-text-block, community-access.github.io#6).
+   github-markdown-css underlines them only on hover. */
+.markdown-body p a,
+.markdown-body li a,
+.markdown-body td a,
+.markdown-body blockquote a,
+.markdown-body dd a {
+  text-decoration: underline;
+  text-underline-offset: 2px;
+}
+
 /* High contrast mode support */
 @media (prefers-contrast: high) {
   body {