diff --git a/src/web-ui/src/infrastructure/config/components/ModelServiceCollapse.presentation.test.ts b/src/web-ui/src/infrastructure/config/components/ModelServiceCollapse.presentation.test.ts
index 661dfb504b..6291c9c4cf 100644
--- a/src/web-ui/src/infrastructure/config/components/ModelServiceCollapse.presentation.test.ts
+++ b/src/web-ui/src/infrastructure/config/components/ModelServiceCollapse.presentation.test.ts
@@ -51,6 +51,9 @@ describe('model service collapsed presentation', () => {
     expect(modelSettingsStyles).toMatch(
       /&__provider-group-header\s*\{[^}]*background:\s*transparent/,
     );
+    expect(modelSettingsStyles).toMatch(
+      /\.openbitfun-collection-item__details\s*\{[^}]*background:\s*transparent/,
+    );
   });
 
   it('draws one consistent divider between provider headers and model rows', () => {
diff --git a/src/web-ui/src/infrastructure/config/components/ModelSettingsPage.scss b/src/web-ui/src/infrastructure/config/components/ModelSettingsPage.scss
index b700e03c7c..2348693fdd 100644
--- a/src/web-ui/src/infrastructure/config/components/ModelSettingsPage.scss
+++ b/src/web-ui/src/infrastructure/config/components/ModelSettingsPage.scss
@@ -235,6 +235,11 @@
 
     .openbitfun-collection-item__details {
       border-top: 1px solid var(--openbitfun-color-border-subtle);
+      // The provider group owns the persistent surface. Reusing the shared
+      // translucent details tint here makes the dark-theme composite nearly
+      // identical to the surrounding scene, leaving a page-colored gutter
+      // around the dashed inset section.
+      background: transparent;
     }
 
     .openbitfun-collection-item__details-toggle {