Apply Second Brain design: Fira Mono, Aubade cards, brand palette

src/components/admin/admin-nav.tsx

@@ -2,7 +2,6 @@
 
 import Link from "next/link";
 import { usePathname } from "next/navigation";
-import { cn } from "@/lib/utils";
 
 const links = [
   { href: "/admin/dashboard", label: "Обзор" },
@@ -15,20 +14,29 @@ export function AdminNav() {
 
   return (
     <>
-      {links.map(({ href, label }) => (
-        <Link
-          key={href}
-          href={href}
-          className={cn(
-            "block px-3 py-2 rounded-lg text-sm transition-colors",
-            pathname === href || (href !== "/admin/dashboard" && pathname.startsWith(href))
-              ? "bg-slate-700 text-white"
-              : "text-slate-300 hover:bg-slate-800 hover:text-white"
-          )}
-        >
-          {label}
-        </Link>
-      ))}
+      {links.map(({ href, label }) => {
+        const active =
+          pathname === href ||
+          (href !== "/admin/dashboard" && pathname.startsWith(href));
+        return (
+          <Link
+            key={href}
+            href={href}
+            className="admin-sidebar-nav-link"
+            style={
+              active
+                ? {
+                    color: "#E8F0D8",
+                    borderLeftColor: "#E8F0D8",
+                    backgroundColor: "var(--sidebar-surface)",
+                  }
+                : undefined
+            }
+          >
+            {label}
+          </Link>
+        );
+      })}
     </>
   );
 }