fix: upgrade rehype-citation and fix styles

css/tailwind.css

@@ -10,6 +10,14 @@
   @apply list-none;
 }
 
+.footnotes {
+  @apply pt-8 mt-12 border-t border-gray-200 dark:border-gray-700;
+}
+
+.csl-entry {
+  @apply my-5;
+}
+
 html {
   scroll-behavior: smooth;
 }