fix: keep workbar tab close background transparent

src/renderer/src/WorkbarShell.test.tsx

@@ -81,6 +81,12 @@ describe('WorkbarShell', () => {
     )
   })
 
+  it('keeps the close control background transparent when a tab reveals it', () => {
+    expect(stylesheet).toMatch(
+      /\.workbar-shell__tab-close\s*\{[^}]*background:\s*transparent;/u
+    )
+  })
+
   it('provides four default single-instance tabs and keeps add outside the tablist', () => {
     render(<ControlledShell />)
 

src/renderer/src/styles.css

@@ -4010,7 +4010,7 @@ button > svg {
   width: 24px;
   min-width: 24px;
   height: 24px;
-  background: var(--surface-raised);
+  background: transparent;
   opacity: 0;
   pointer-events: none;
   transform: translateY(-50%) scale(0.86);