fix: update AboutUs component typography and layout for consistency

Author: BIA3IA

src/components/home/about-us.tsx

@@ -2,9 +2,9 @@ import { Button } from "@/components/ui/button"
 
 export function AboutUs() {
   return (
-    <section className="mx-auto flex min-h-screen w-full max-w-4xl flex-col items-center justify-center gap-24 px-6 py-12 text-center">
-      <h1 className="typo-display-medium lg:typo-display-large bg-linear-to-r from-text-primary via-blue-secondary to-blue-primary bg-clip-text text-transparent">
-        PoliNetwork unisce gli studenti del Poli con gruppi, risorse e supporto in un'unica community.
+    <section className="mx-auto flex min-h-screen w-full max-w-4xl flex-col items-center justify-center gap-16 px-7.5 py-12 text-center sm:gap-24">
+      <h1 className="typo-headline-medium sm:typo-display-large bg-linear-to-r from-text-primary via-blue-secondary to-blue-primary bg-clip-text text-transparent">
+        PoliNetwork unisce gli studenti del Poli: gruppi, risorse e supporto, tutti in un'unica community.
       </h1>
 
       <Button variant="primary" size="lg">