Fix show-page downloads button contrast

Author: srappel

app/assets/stylesheets/uwm.scss

@@ -22,6 +22,15 @@
   color: $black;
 }
 
+.downloads-sidebar .btn-primary,
+.downloads-sidebar .btn-primary:hover,
+.downloads-sidebar .btn-primary:focus,
+.downloads-sidebar .btn-primary:not(:disabled):not(.disabled):active,
+.downloads-sidebar .btn-primary:not(:disabled):not(.disabled).active,
+.downloads-sidebar .show > .btn-primary.dropdown-toggle {
+  color: $black;
+}
+
 .screen-reader-text {
   @include sr-only;
 }

test/system/accessibility_test.rb

@@ -14,4 +14,25 @@ def test_search_results_have_no_critical_accessibility_violations
 
     assert_no_axe_violations
   end
+
+  def test_show_page_download_button_has_dark_text
+    visit("/catalog/stanford-cz128vq0535")
+
+    assert page.has_selector?("#downloads-button")
+
+    styles = page.evaluate_script(<<~JS)
+      (() => {
+        const button = document.querySelector("#downloads-button");
+        const computed = window.getComputedStyle(button);
+
+        return {
+          color: computed.color,
+          background_color: computed.backgroundColor
+        };
+      })()
+    JS
+
+    assert_equal "rgb(0, 0, 0)", styles["color"]
+    assert_equal "rgb(255, 189, 0)", styles["background_color"]
+  end
 end