diff --git a/content_script.js b/content_script.js
index dfe5d44..03bddd0 100644
--- a/content_script.js
+++ b/content_script.js
@@ -1,4 +1,4 @@
-function addButton(){
+function addButton() {
     const sidebar = document.querySelector(".window-sidebar")
     const button = document.createElement('span');
     button.classList.add('button-link');
@@ -13,16 +13,66 @@ function addButton(){
     const buttonText = document.createElement('span');
     buttonText.innerText = 'Toggl Task';
     button.append(buttonText);
-    
+
+    sidebar.querySelector(".mod-no-top-margin").classList.remove("mod-no-top-margin")
     sidebar.querySelector(".js-sidebar-add-heading").classList.remove("mod-no-top-margin")
 }
 
-function onClick(){
-    alert("work in progress ;)")
+const mappings = {
+    "GG": "gg",
+    "Audience Builder": "ab",
+    "Audience Explorer": "ae",
+    "Cta Calls": "xcta",
+    "Camper": "camper",
+};
+
+function onClick() {
+    let apiKey = "afadffe77f745496f80ebb4bf460c615"
+    //generate token at https://trello.com/1/authorize?expiration=never&scope=read,write,account&response_type=token&name=Server%20Token&key=afadffe77f745496f80ebb4bf460c615
+    let token = "***"
+    console.log("Hallo")
+    const longId = window.location.pathname.split("/")[2];
+    var url = `https://api.trello.com/1/cards/${longId}?key=${apiKey}&token=${token}`
+    fetch(url).then(response => response.json()).then(response => {
+        shortId = response["idShort"]
+
+        if (!response["name"].endsWith(shortId)) {
+            for (var i in response["labels"]) {
+                if (labelShort == undefined) {
+                    var labelShort = mappings[response["labels"][i]["name"]]
+                } else if (mappings[response["labels"][i]["name"]] != undefined) {
+                    alert(`Diese Karte hat sowohl "${labelShort}" als auch "${mappings[response["labels"][i]["name"]]}".`)
+                }
+            }
+
+            if (labelShort != undefined) {
+
+
+                const url = new URL(`https://api.trello.com/1/cards/${longId}`)
+                console.log(url)
+
+                const data = {
+                    "name": `${response["name"]} #${labelShort}_${shortId}`
+                };
+                const jsonBody = JSON.stringify(data);
+                fetch(url.toString(), {
+                    method: 'PUT',
+                    headers: {
+                        'Authorization': `OAuth oauth_consumer_key="${apiKey}", oauth_token="${token}"`,
+                        'Content-Type': 'application/json'
+                    },
+                    body: jsonBody
+                }).then(response => {
+                    console.log(response)
+                })
+            }
+        }
+
+    })
 }
 
-window.addEventListener("pushstate", function(){
-    if(window.location.pathname.startsWith("/c/")){
+window.addEventListener("pushstate", function () {
+    if (window.location.pathname.startsWith("/c/")) {
         addButton()
     }
 })
diff --git a/manifest.json b/manifest.json
index 78d6087..6c61666 100644
--- a/manifest.json
+++ b/manifest.json
@@ -18,6 +18,10 @@
     }
   ],
 
+  "permissions": [
+    "*://api.trello.com/*"
+  ],
+
   "options_ui": {
     "page": "options/index.html"
   }