diff --git a/themes/demula/demula.theme.bash b/themes/demula/demula.theme.bash
old mode 100644
new mode 100755
index e85c18f7..7d8d6cc8
--- a/themes/demula/demula.theme.bash
+++ b/themes/demula/demula.theme.bash
@@ -98,7 +98,7 @@ prompt() {
   local MOVE_CURSOR_RIGHTMOST='\033[500C'
   local MOVE_CURSOR_5_LEFT='\033[5D'
 
-  if [ $(uname) = "Linux" ];
+  if [[ "$OSTYPE" = 'linux'* ]]
   then
     PS1="${TITLEBAR}${SAVE_CURSOR}${MOVE_CURSOR_RIGHTMOST}${MOVE_CURSOR_5_LEFT}
 $(safe_battery_charge)${RESTORE_CURSOR}\