OnlineBoardSearchPage retry button: $blue-light fill + $blue-light--hover (brand button parity)

src/features/online-board/components/OnlineBoardSearchPage.scss

@@ -47,19 +47,24 @@
     font-size: 14px;
   }
 
+  // Matches the standard `.color.blue-light` button used across Angular
+  // (see _buttons.scss) — $blue-light fill with $blue-light--hover on
+  // hover. Replaces the prior `opacity: 0.9` hover which just darkened
+  // the whole button.
   &__retry-btn {
     display: inline-block;
     padding: vars.$space-s2 vars.$space-xl;
-    background-color: colors.$blue;
+    background-color: colors.$blue-light;
     color: colors.$white;
     border: none;
     border-radius: vars.$border-radius;
     cursor: pointer;
     font-size: 14px;
     font-weight: 500;
+    transition: background-color 150ms ease;
 
     &:hover {
-      opacity: 0.9;
+      background-color: colors.$blue-light--hover;
     }
   }