Refactor frontend system primitives and surfaces

components/dashboard/dashboard-card.tsx

@@ -22,7 +22,7 @@ export function DashboardCard({
           <CardDescription>{title}</CardDescription>
           <CardTitle className="text-3xl font-semibold tracking-tight">{value}</CardTitle>
         </div>
-        <div className="rounded-md border border-border bg-muted/60 p-2 text-muted-foreground">
+        <div className="rounded-nested border border-border bg-muted/60 p-2 text-muted-foreground">
           <Icon className="h-4 w-4" />
         </div>
       </CardHeader>

components/dashboard/dashboard-layout.tsx

@@ -84,7 +84,7 @@ export function DashboardLayout({
 
             <div className="flex min-w-0 flex-1 items-center gap-3">
               {Icon ? (
-                <div className="hidden rounded-lg border border-border/70 bg-muted/50 p-2 text-muted-foreground sm:flex">
+                <div className="hidden rounded-nested border border-border/70 bg-muted/50 p-2 text-muted-foreground sm:flex">
                   <Icon className="h-4 w-4" />
                 </div>
               ) : null}