Educate this rule

website/pages/style.css

@@ -98,7 +98,19 @@
   color: white;
 }
 
-/* Permalink adjustment for sticky nav */
+/*
+ * About this selector:
+ * `.g-subnav ~ *` finds all elements after the navigation.
+ * `:target` finds the active permalink on the page.
+ *
+ * About this style:
+ * `scroll-margin-top` adjusts the vertical scroll of a permalink.
+ * `64px` adjusts the scroll to account for the navigation.
+ * `0.5em` further adjusts the scroll to give the permalink breathing room.
+ *
+ * See: https://developer.mozilla.org/en-US/docs/Web/CSS/:target
+ * See: https://developer.mozilla.org/en-US/docs/Web/CSS/scroll-margin-top
+ */
 .g-subnav ~ * :target {
   scroll-margin-top: calc(64px + 0.5em);
 }