Move e-payment to Settings and add ZarinPal credentials.

Gateway config now lives on the general Settings page, with Mellat fields in a 3-column layout and ZarinPal available at checkout.

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/business/src/components/VariationsModal.module.css

@@ -2,8 +2,8 @@
   position: fixed;
   inset: 0;
   background: var(--modal-overlay-bg);
-  backdrop-filter: blur(var(--modal-overlay-blur));
-  -webkit-backdrop-filter: blur(var(--modal-overlay-blur));
+  backdrop-filter: blur(var(--modal-overlay-blur, 16px));
+  -webkit-backdrop-filter: blur(var(--modal-overlay-blur, 16px));
   display: flex;
   align-items: center;
   justify-content: center;
@@ -11,6 +11,14 @@
   padding: 20px;
 }
 
+.overlayIn {
+  animation: overlayFadeIn 0.2s ease forwards;
+}
+
+.overlayOut {
+  animation: overlayFadeOut 0.18s ease forwards;
+}
+
 .overlayNested {
   z-index: 1010;
 }
@@ -417,6 +425,16 @@
   color: #ef4444;
   margin-bottom: 12px;
 }
+@keyframes overlayFadeIn {
+  from { opacity: 0; }
+  to { opacity: 1; }
+}
+
+@keyframes overlayFadeOut {
+  from { opacity: 1; }
+  to { opacity: 0; }
+}
+
 @keyframes modalFadeIn {
   from { opacity: 0; transform: translateY(12px) scale(0.98); }
   to { opacity: 1; transform: translateY(0) scale(1); }