OpenSpending Data Portal (#868)

* [#856,openspending][xl]: initial commit

* [examples/openspending][xs] - remove console.logs

---------

Co-authored-by: Luccas Mateus de Medeiros Gomes <luccasmmg@gmail.com>

examples/openspending/components/Header.tsx

@@ -0,0 +1,54 @@
+import Image from 'next/image'
+import { Button } from './Button'
+import { Container } from './Container'
+import logo from "../public/logo.svg"
+import Link from 'next/link'
+import { useRouter } from 'next/router'
+
+export function Header() {
+  const router = useRouter();
+
+  const isActive = (navLink) => {
+    return router.asPath.split("?")[0] == navLink.href;
+  }
+
+  const navLinks = [
+    {
+      title: "Home",
+      href: "/#header"
+    },
+    {
+      title: "Datasets",
+      href: "/#datasets"
+    },
+    {
+      title: "Community",
+      href: "https://community.openspending.org/"
+    }
+  ]
+
+  return (
+    <header className="z-50 pb-5 lg:pt-11 sticky top-0 backdrop-blur" id="header">
+      <Container className="flex flex-wrap items-center justify-center sm:justify-between lg:flex-nowrap">
+        <div className="mt-10 lg:mt-0 lg:grow lg:basis-0 flex items-center">
+          <Image src={logo} alt="OpenSpending" className="h-12 w-auto" />
+        </div>
+        <ul className='list-none flex gap-x-5 text-base font-medium'>
+          {navLinks.map((link, i) => (
+            <li key={`nav-link-${i}`}>
+              <Link
+                className={`text-emerald-900 hover:text-emerald-600 ${isActive(link) ? "text-emerald-600" : ""}`}
+                href={link.href}
+                scroll={false}
+              >
+                {link.title}
+              </Link>
+            </li>))}
+        </ul>
+        <div className="hidden sm:mt-10 sm:flex lg:mt-0 lg:grow lg:basis-0 lg:justify-end">
+          <Button href="#">View on GitHub</Button>
+        </div>
+      </Container>
+    </header >
+  )
+}