design: implement blurred dashboard overlays and 5-item symmetric 2x2 grid with full-width I'm not sure tile at the bottom

vibn-frontend/_onboarding/onboarding-entrepreneur.tsx

@@ -255,6 +255,8 @@ function LayoutPreview({ styleId }: { styleId: string }) {
         background: c.bg,
         color: c.text,
         overflow: "hidden",
+        filter: "blur(3.5px)",
+        pointerEvents: "none",
       }}
     >
       {/* Header */}
@@ -2238,7 +2240,15 @@ function LayoutPreview({ styleId }: { styleId: string }) {
   );
 }
 
-const SAAS_STYLES = [
+interface StyleOption {
+  id: string;
+  label: string;
+  desc: string;
+  illustration: React.ReactNode;
+  fullWidth?: boolean;
+}
+
+const SAAS_STYLES: StyleOption[] = [
   {
     id: "sidebar_light",
     label: "Vertical Sidebar — Light",
@@ -2263,9 +2273,16 @@ const SAAS_STYLES = [
     desc: "Full dark topbar + dark dashboard layouts.",
     illustration: <LayoutPreview styleId="topbar_dark" />,
   },
+  {
+    id: "not_sure",
+    label: "I'm not sure",
+    desc: "Let Vibn help you decide based on your description",
+    fullWidth: true,
+    illustration: <LayoutPreview styleId="not_sure" />,
+  },
 ];
 
-const MARKETPLACE_STYLES = [
+const MARKETPLACE_STYLES: StyleOption[] = [
   {
     id: "flux",
     label: "Dark Glass / Flux",
@@ -2280,7 +2297,7 @@ const MARKETPLACE_STYLES = [
   },
 ];
 
-const GENERAL_STYLES = [
+const GENERAL_STYLES: StyleOption[] = [
   {
     id: "bento",
     label: "Dark Bento",
@@ -2331,6 +2348,7 @@ function EntrepStyle({ productType, value, onChange }) {
           desc: s.desc,
           icon: undefined,
           illustration: s.illustration,
+          fullWidth: s.fullWidth,
         }))}
         value={value}
         onChange={onChange}