Remove syntax highlighting colors from type signatures

Author: st0012

lib/rdoc/generator/template/aliki/css/rdoc.css

@@ -1075,19 +1075,18 @@ main h6 a:hover {
   font-style: italic;
 }
 
-/* RBS Type Signature Highlighting — only types and builtins get color */
-.rbs-type    { color: var(--code-blue); }
-.rbs-builtin { color: var(--code-purple); }
-
+/* RBS Type Signature Highlighting — linked types get subtle underline */
 a.rbs-type {
+  color: inherit;
   text-decoration: underline;
   text-decoration-color: var(--color-border-default);
   text-underline-offset: 0.2em;
-  transition: text-decoration-color var(--transition-fast);
+  transition: text-decoration-color var(--transition-fast), color var(--transition-fast);
 }
 
 a.rbs-type:hover {
-  text-decoration-color: currentColor;
+  color: var(--color-link-hover);
+  text-decoration-color: var(--color-link-hover);
 }
 
 /* Emphasis */