More code cleanup and optimization

frontend/src/styles.css

@@ -32,12 +32,6 @@ body,
 }
 
 body {
-  font-family:
-    system-ui,
-    -apple-system,
-    BlinkMacSystemFont,
-    'Segoe UI',
-    sans-serif;
   /* Prevent overscroll/bounce on mobile */
   overscroll-behavior: none;
   padding: var(--safe-area-top) var(--safe-area-right) var(--safe-area-bottom-capped)
@@ -50,13 +44,6 @@ body {
   box-sizing: border-box;
 }
 
-/* Fallback for browsers without dvh support */
-@supports not (height: 1dvh) {
-  .h-dvh {
-    height: 100vh;
-  }
-}
-
 /* Mobile sidebar override - ensures sidebar fills Sheet container */
 [data-state] .sidebar {
   width: 100%;