diff --git a/vpn.bash b/vpn.bash
index 29e6ca2..ce5259e 100755
--- a/vpn.bash
+++ b/vpn.bash
@@ -12,14 +12,14 @@ resolved_conf_d=(
 function stopvpn() {
   mapfile -t vpn_pid <<< "$(pgrep openfortivpn) $(pgrep openvpn) $(pgrep openconnect)" 
 
-  for pid in ${vpn_pid[@]}; do
+  for pid in "${vpn_pid[@]}"; do
     if [[ -n "$pid" ]]; then
       echo "Kill process $pid."
       sudo kill "$pid"
     fi
   done
 
-  for conf in ${resolved_conf_d[@]}; do
+  for conf in "${resolved_conf_d[@]}"; do
     if [[ -e "/etc/systemd/resolved.conf.d/$conf" ]]; then
       sudo rm "/etc/systemd/resolved.conf.d/$conf"
     fi
@@ -118,4 +118,4 @@ function main() {
   esac
 }
 
-main $@
+main "$@"