class CodeEditor extends HTMLElement { connectedCallback() { this.attachShadow({ mode: 'open' }); this.shadowRoot.innerHTML = `

code.js

 const encodeMessage = (message) => {
   return btoa(encodeURIComponent(message));
 };
 
 const decodeMessage = (encoded) => {
   try {
     return decodeURIComponent(atob(encoded));
   } catch (e) {
     return "Invalid encoding";
   }
 };
 
 // Example usage:
 const secret = "Hello World!";
 const encoded = encodeMessage(secret);
 const decoded = decodeMessage(encoded);

`; } } customElements.define('code-editor', CodeEditor);