style(src/styles/window): darken panel and notch background colors

src/styles/window/panel.css

@@ -92,22 +92,15 @@
 }
 
 #panel-notch-stack {
-    background-color: #000000;
+    background-color: #111111;
     border-radius: 0 0 apply(radius-lg) apply(radius-lg);
     min-width: 200px;
     min-height: 34px;
 }
 
-#panel-notch-left-corner {
-    margin-left: -16px;
-}
-
-#panel-notch-right-corner {
-    margin-right: -16px;
-}
 
 #panel-notch-corner {
-    background-color: #000000;
+    background-color: #111111;
     border-radius: 0;
     min-width: 20px;
     min-height: 20px;