feat: enhance UI components and layout styling

- Updated FeatureDescription text size to be larger on desktop (lg:text-base)
- Added rounded corners (rounded-3xl) to DarkCard component
- Modified CloudArchitecture section with wider container (max-w-5xl) and updated heading styles
- Adjusted mobile feature navigation indicators with darker colors (bg-gray-600/700)
- Improved hero section typography using H2 and H5 components for better hierarchy
- Refined padding and background styling in CloudFeatures mobile

src/pages/cloud/CloudArchitecture.tsx

@@ -1,5 +1,5 @@
 import { Container } from '../../components/Container'
-import { Eyebrow, SectionHeader, P } from '../../components/Texts'
+import { Eyebrow, H3, P } from '../../components/Texts'
 
 const architectureSections = [
   {
@@ -39,15 +39,15 @@ const architectureSections = [
 
 export function CloudArchitecture() {
   return (
-    <section className="bg-white py-24 sm:py-32">
+    <section className="bg-white py-24 lg:py-32">
       <Container>
-        <div className="mx-auto max-w-3xl text-center">
+        <div className="mx-auto max-w-5xl text-center">
           <Eyebrow>
             Technical Architecture
           </Eyebrow>
-          <SectionHeader as="h2" className="mt-6 text-gray-900">
-            Built on a sovereign, encrypted delivery mesh.
-          </SectionHeader>
+          <H3 className="mt-6 text-gray-900">
+            Built on a Sovereign, Encrypted Delivery Mesh.
+          </H3>
           <P className="mt-6 text-gray-600">
             Mycelium Cloud rides on the ThreeFold Grid, pairing encrypted mesh
             networking with deterministic K3s orchestration. Every layer is