add: code hide button

src/lib/components/Markdown.svelte

@@ -1,6 +1,8 @@
 <script>
     export let mdtext;
 
+    import { onMount } from "svelte";
+
     import { remark } from 'remark'
     import remarkgfm from 'remark-gfm'
     import remarkBreaks from "remark-breaks"
@@ -28,6 +30,27 @@
         .use(rehypeStringify, {allowDangerousHtml: true})
         .processSync(mdtext)
 
+    onMount(()=>{
+        let toggleHide = function(e){
+
+            let iframes = document.getElementsByTagName('iframe')
+            for ( let i = 0; i < iframes.length; i++ ){
+                try{
+                    console.log(iframes[i].contentWindow.name)
+                    if (e.origin === window.origin && iframes[i].contentWindow.name == e.data.id){
+                        iframes[i].classList.toggle('hide')
+                    }
+                }catch(e){
+                    console.log(e)
+                }
+            }
+        }
+        
+        window.addEventListener('message', toggleHide)
+
+        return ()=>{window.removeEventListener('message', toggleHide)}
+    })
+
 </script>
 
 <div class='markdown'>