diff --git a/content/js/shell/index.js b/content/js/shell/index.js
index fa9f6c8..2eb1ed8 100644
--- a/content/js/shell/index.js
+++ b/content/js/shell/index.js
@@ -1,7 +1,7 @@
-let cmd_prompt = document.getElementById('prompt');
-let cmd_output = document.getElementById('command_output');
-let cmd_history = document.getElementById('cmd_hist');
-let shell = document.getElementById('shell');
+const cmd_prompt = document.getElementById('prompt');
+const cmd_output = document.getElementById('command_output');
+const cmd_history = document.getElementById('cmd_hist');
+const shell = document.getElementById('shell');
 var is_root = false;
 
 function main() {