diff --git a/app/templates/index.html b/app/templates/index.html
index 56da1b9..f58f0db 100644
--- a/app/templates/index.html
+++ b/app/templates/index.html
@@ -40,6 +40,28 @@
             max-width: 100%;
         }
     }
+
+    /* Modal fullscreen - remove all margins and padding */
+    #dmModal .modal-dialog.modal-fullscreen,
+    #contactsModal .modal-dialog.modal-fullscreen {
+        margin: 0 !important;
+        width: 100vw !important;
+        max-width: 100vw !important;
+        height: 100vh !important;
+        max-height: 100vh !important;
+    }
+
+    #dmModal .modal-content,
+    #contactsModal .modal-content {
+        border: none !important;
+        border-radius: 0 !important;
+        height: 100vh !important;
+    }
+
+    #dmModal .modal-body,
+    #contactsModal .modal-body {
+        overflow: hidden !important;
+    }
 </style>
 {% endblock %}