feat: enhance WelcomeBanner with settings button and update styles for better layout

app/[locale]/page.tsx

@@ -1044,6 +1044,7 @@ export default function Home() {
               )}
             </div>
 
+            <div className="flex-1 min-h-0 flex flex-col">
             <WelcomeBanner />
 
             <ErrorBoundary fallback={EmailListErrorFallback}>
@@ -1100,9 +1101,10 @@ export default function Home() {
                   selectEmail(email);
                   await handleUndoSpam();
                 }}
-                className="flex-1"
+                className="flex-1 min-h-0"
               />
             </ErrorBoundary>
+            </div>
           </div>
 
           {/* Email list resize handle (desktop only) */}

app/globals.css

@@ -92,6 +92,10 @@ body {
   min-width: 100%;
 }
 
+.email-content-text {
+  padding: 1rem 1.25rem;
+}
+
 .email-content {
   font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
   font-size: 0.9375rem;
@@ -100,6 +104,12 @@ body {
   max-width: none;
   overflow-wrap: break-word;
   word-wrap: break-word;
+  padding: 1rem 1.25rem;
+}
+
+/* Remove padding for rich HTML emails with table-based layouts */
+.email-content:has(> table) {
+  padding: 0;
 }
 
 .email-content p {