feat(ui): style sidebar and landing page (#27)

packages/bolt/app/components/header/Header.tsx

@@ -1,20 +1,26 @@
+import { useStore } from '@nanostores/react';
 import { ClientOnly } from 'remix-utils/client-only';
-import { IconButton } from '~/components/ui/IconButton';
+import { chatStore } from '~/lib/stores/chat';
+import { classNames } from '~/utils/classNames';
 import { OpenStackBlitz } from './OpenStackBlitz.client';
 
 export function Header() {
+  const chat = useStore(chatStore);
+
   return (
-    <header className="flex items-center bg-white p-4 border-b border-gray-200 h-[var(--header-height)]">
+    <header
+      className={classNames('flex items-center bg-white p-5 border-b h-[var(--header-height)]', {
+        'border-transparent': !chat.started,
+        'border-gray-200': chat.started,
+      })}
+    >
       <div className="flex items-center gap-2">
         <a href="/" className="text-2xl font-semibold text-accent">
-          Bolt
+          <img src="/logo_text.svg" width="60px" alt="Bolt Logo" />
         </a>
       </div>
       <div className="ml-auto flex gap-2">
         <ClientOnly>{() => <OpenStackBlitz />}</ClientOnly>
-        <a href="/logout">
-          <IconButton icon="i-ph:sign-out" />
-        </a>
       </div>
     </header>
   );