refactor header to sticky with scroll-based background blur

src/app/page.tsx

@@ -7,14 +7,16 @@ import { HomePrinciples } from '@/components/HomePrinciples'
 import { HomeMilestones } from '@/components/HomeMilestones'
 import { HomeVentures } from '@/components/HomeVentures'
 import { Quote } from '@/components/Quote'
-import { Header_darkbg } from '@/components/Header_darkbg'
+import { HomeStickyHeader } from '@/components/HomeStickyHeader'
 
 export default function Home() {
   return (
     <>
-      <Header_darkbg />
       <main>
-        <Hero />
+        <HomeStickyHeader />
+        <section className="relative min-h-screen">
+          <Hero className="-mt-20" />
+        </section>
         <HomeAbout />
         <HomePrinciples />
         <HomeMilestones />