Apply theming to modals

output/index.css

@@ -431,8 +431,8 @@ label[for=toggle-show-room-ids]::after {
 
 }
 .qr-code-modal-content {
-	background-color: #ffffff;
-	border: 1px solid #000000;
+	background-color: var(--secondary-color);
+	border: 1px solid var(--primary-color);
 	width: 80%;
 	margin: auto;
 	padding: 20px;
@@ -441,13 +441,13 @@ label[for=toggle-show-room-ids]::after {
 	float: right;
 	font-size: 35px;
 	font-weight: bold;
-	color: #aaaaaa;
+	color: var(--primary-color);
+	opacity: 60%
 }
 .qr-code-modal-close:hover,
 .qr-code-modal-close:focus {
 	cursor: pointer;
-	text-decoration: none;
-	color: #000000;
+	opacity: 100%
 }
 
 /* <Snackbar> */