adjust modal width

src/client/styles/scss/_override-bootstrap.scss

@@ -136,6 +136,10 @@ h5 {
   box-shadow: 0 0.3rem 1rem rgba(0, 0, 0, 0.1);
 }
 
+.modal-dialog {
+  max-width: 600px;
+}
+
 .modal-header {
   border-bottom: 1px solid #e5e5e5;
 }