diff --git a/src/define.sh b/src/define.sh
index ae32c24..7bbe4f3 100644
--- a/src/define.sh
+++ b/src/define.sh
@@ -24,7 +24,7 @@ parseVersion() {
     VERSION="${VERSION:1:-1}"
   fi
   
-  VERSION=`expr "$VERSION" : "^\ *\(.*[^ ]\)\ *$"`
+  VERSION=$(expr "$VERSION" : "^\ *\(.*[^ ]\)\ *$")
   [ -z "$VERSION" ] && VERSION="win11"
 
   case "${VERSION,,}" in