fix(instructure): don't require nebula

Author: lishaduck

websites/+instructure.com.css

@@ -1,4 +1,4 @@
-/* transparency */
+/* canvas-transparency */
 .ic-Dashboard-header,
 .ic-Dashboard-header__layout,
 #dashboard-planner-header,
@@ -24,16 +24,16 @@ header {
   transition: background-color 0.5s ease-in-out, background 0.5s ease-in-out, border 0.5s ease-in-out, box-shadow 0.5s ease-in-out !important;
 }
 
-/* sidebar legibility */
+/* canvas-sidebar */
 .navigation-tray-container {
-  background: var(--natsumi-glass-background) !important;
+  background: color-mix(in srgb, var(--natsumi-colors-secondary, color-mix(in srgb, #101010 30%, #202020 70%)) 60%, transparent) !important;
   border-radius: 16px !important;
   box-shadow: 0 4px 30px rgba(0, 0, 0, 0.1) !important;
   backdrop-filter: blur(var(--glass-blur-radius, 10px));
   border: 1px solid rgba(200, 200, 200, 0.1) !important; /* Optional subtle border */
 }
 
-/* darkreader */
+/* canvas-darkreader */
 :root {
   --darkreader-background-ffffff: transparent !important;
 }