diff --git a/res/themes/dharma/css/_dharma.scss b/res/themes/dharma/css/_dharma.scss
index 0851762be2..08a287ad71 100644
--- a/res/themes/dharma/css/_dharma.scss
+++ b/res/themes/dharma/css/_dharma.scss
@@ -186,6 +186,8 @@ $lightbox-border-color: #ffffff;
 // unused?
 $progressbar-color: #000;
 
+$room-warning-bg-color: #fff8e3;
+
 /*** form elements ***/
 
 // .mx_textinput is a container for a text input
@@ -320,3 +322,11 @@ input[type=search]::-webkit-search-results-decoration {
     font-size: 15px;
     padding: 0px 1.5em 0px 1.5em;
 }
+
+@define-mixin mx_DialogButton_secondary {
+    // flip colours for the secondary ones
+    font-weight: 600;
+    border: 1px solid $accent-color ! important;
+    color: $accent-color;
+    background-color: $accent-fg-color;
+}