feat: improve newsletter email design and buttons

- Change game button to redirect to /jeux instead of /register
- Improve button colors: orange/red for primary, gold for secondary
- Add hover effects with shadows and transform animations
- Remove unsubscribe section from footer
- Clean up email subject: remove emoji, keep professional format
- Increase button font size and add letter spacing for better readability

Button improvements:
- Primary button (Jouer Maintenant): vibrant orange gradient (#f59e0b → #ea580c)
- Secondary button (Visiter le Site): gold gradient matching brand colors
- Enhanced shadows and hover effects for better interactivity

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/services/newsletter.service.js

@@ -65,7 +65,8 @@ const sendEmail = async ({ to, subject, html, text }) => {
 export const sendNewsletterConfirmationEmail = async (email) => {
   const unsubscribeUrl = `${process.env.FRONTEND_URL || 'http://localhost:3000'}/newsletter/unsubscribe?email=${encodeURIComponent(email)}`;
   const siteUrl = process.env.FRONTEND_URL || 'http://localhost:3000';
-  const gameUrl = `${siteUrl}/game`;
+  // Bouton "Jouer Maintenant" redirige vers /jeux
+  const gameUrl = `${siteUrl}/jeux`;
   const currentDate = new Date().toLocaleString('fr-FR', {
     day: '2-digit',
     month: '2-digit',
@@ -225,20 +226,31 @@ export const sendNewsletterConfirmationEmail = async (email) => {
           display: inline-block;
           padding: 18px 40px;
           margin: 10px 8px;
-          font-size: 16px;
+          font-size: 17px;
           font-weight: bold;
           text-decoration: none;
           border-radius: 50px;
           transition: all 0.3s ease;
-          box-shadow: 0 4px 15px rgba(0,0,0,0.2);
+          box-shadow: 0 6px 20px rgba(0,0,0,0.25);
+          letter-spacing: 0.5px;
         }
         .button-primary {
-          background: linear-gradient(135deg, #d4a574 0%, #c4956a 100%);
+          background: linear-gradient(135deg, #f59e0b 0%, #ea580c 100%);
           color: white;
+          border: 2px solid transparent;
+        }
+        .button-primary:hover {
+          box-shadow: 0 8px 25px rgba(245, 158, 11, 0.4);
+          transform: translateY(-2px);
         }
         .button-secondary {
-          background: linear-gradient(135deg, #5a5a4e 0%, #4a4a42 100%);
+          background: linear-gradient(135deg, #d4a574 0%, #c4956a 100%);
           color: white;
+          border: 2px solid transparent;
+        }
+        .button-secondary:hover {
+          box-shadow: 0 8px 25px rgba(212, 165, 116, 0.4);
+          transform: translateY(-2px);
         }
         .info-box {
           background: white;
@@ -399,12 +411,6 @@ export const sendNewsletterConfirmationEmail = async (email) => {
             <div class="footer-logo">🍃 Thé Tip Top</div>
             <div class="footer-title">Votre spécialiste du thé d'exception</div>
             <p class="footer-date">📧 Newsletter envoyée le ${currentDate}</p>
-            <div class="unsubscribe">
-              <p>
-                Vous ne souhaitez plus recevoir nos emails ?<br>
-                <a href="${unsubscribeUrl}">Se désinscrire</a>
-              </p>
-            </div>
             <p style="margin-top: 20px; font-size: 12px; opacity: 0.7;">
               © 2025 Thé Tip Top - Tous droits réservés
             </p>
@@ -448,7 +454,7 @@ Pour vous désinscrire : ${unsubscribeUrl}
 
   return sendEmail({
     to: email,
-    subject: '🍃 Thé Tip Top | Bienvenue dans la newsletter - Jeu Concours 🎉',
+    subject: 'Thé Tip Top | Bienvenue dans la newsletter - Jeu Concours 🎉',
     html,
     text,
   });