apply monospace font correctly

res/css/_common.scss

@@ -32,6 +32,10 @@ body {
     margin: 0px;
 }
 
+code {
+    font-family: $monospace-font-family;
+}
+
 .error, .warning {
     color: $warning-color;
 }

res/css/views/rooms/_EventTile.scss

@@ -411,6 +411,7 @@ limitations under the License.
 
 .mx_EventTile_content .markdown-body {
     pre, code {
+        font-family: $monospace-font-family ! important;
         // deliberate constants as we're behind an invert filter
         color: #333;
     }

res/themes/light/css/_light.scss

@@ -7,6 +7,10 @@
    to native Emoji fonts (if any) to ensure cross-browser consistency */
 $font-family: Nunito, Arial, Helvetica, Sans-Serif, 'Twemoji Mozilla';
 
+// XXX: In theory this should be Fira, but it's a bit ugly.
+// TODO: make it consistent cross-browser
+$monospace-font-family: Consolas, 'Liberation Mono', Menlo, Courier, monospace, 'Twemoji Mozilla';
+
 // unified palette
 // try to use these colors when possible
 $accent-color: #03b381;