176 navbar (#177)

## Summary
- Fix the navbar color for ALL JSconf sections

## Screenshots
### Before

![176_previa_before](https://user-images.githubusercontent.com/238259/209372097-8f1f0ebb-8781-49f4-8968-18f7c5a0c1a0.png)

![176_section_before](https://user-images.githubusercontent.com/238259/209372101-3a484c0e-7252-4e07-833b-2f07f47174b4.png)

![176_landing_before](https://user-images.githubusercontent.com/238259/209372104-d2faf2de-957a-4ecc-a3dd-5f4569eaed2f.png)


### After

![176_previa_after](https://user-images.githubusercontent.com/238259/209371928-88db8704-88e2-4afd-95c3-4b51c7ec5944.png)

![176_jsconf_after](https://user-images.githubusercontent.com/238259/209371935-f4c3318e-d2bd-4c12-9a6e-165abdc7f311.png)

![176_landing_after](https://user-images.githubusercontent.com/238259/209371938-b4dacc4e-b217-4d2b-92b8-2918f1bf97dc.png)

## Solves
Solves #176

pages/_app.tsx

@@ -24,7 +24,7 @@ import { Provider } from "urql";
 import { urlQlient } from "../src/graphql/urql";
 import { isAuthenticatedAtom } from "../src/helpers/auth";
 import { GlobalStyles } from "../styles/globalStyles";
-import { jsconfTheme, previaTheme } from "../styles/theme";
+import { jsconfTheme, landingTheme, previaTheme } from "../styles/theme";
 
 const WebSchema = dynamic(
   async () => await import("../src/Components/schema/webpage"),
@@ -108,14 +108,18 @@ const AppWithQueryClients = ({
       })
   );
 
+  const theme =
+    {
+      "/laprevia": previaTheme,
+      "/": landingTheme,
+    }[pathname] ?? jsconfTheme;
+
   return (
     <CacheProvider value={cache}>
       <Provider value={urlQlient}>
         <TanstackQueryProvider client={queryClient}>
           <Hydrate state={(pageProps as any).dehydratedState}>
-            <ThemeProvider
-              theme={pathname === "/laprevia" ? previaTheme : jsconfTheme}
-            >
+            <ThemeProvider theme={theme}>
               <GlobalStyles />
               <Suspense fallback={null}>
                 <WebSchema />

styles/theme.ts

@@ -106,8 +106,8 @@ const theme: Theme = {
       },
     },
     navBar: {
-      textColor: colors.jsconfBlack,
-      activeTextColor: colors.jsconfBlack,
+      textColor: colors.white,
+      activeTextColor: colors.jsconfRed,
       mobileTextColor: colors.jsconfBlack,
       activeMobileTextColor: colors.jsconfRed,
     },
@@ -132,6 +132,17 @@ export const jsconfTheme: Theme = {
   ...theme,
 };
 
+export const landingTheme: Theme = {
+  ...theme,
+  elements: {
+    ...theme.elements,
+    navBar: {
+      ...theme.elements.navBar,
+      textColor: colors.jsconfBlack,
+    },
+  },
+};
+
 export const previaTheme: Theme = {
   ...theme,
   colors: {