minor: make README.md look more friendly + add image

README.md

@@ -1,13 +1,14 @@
-## fxTikTok
-Embed TikTok videos and slideshows on Discord with just **s/i/n**
-
+# 📦 fxTikTok
 [![Deploy to Cloudflare Workers](https://deploy.workers.cloudflare.com/button)](https://deploy.workers.cloudflare.com/?url=https://github.com/okdargy/fxtiktok)
 
-### Setup
-```
-npm install
-npm run dev
-```
-```
-npm run deploy
-```
+Embed TikTok videos and slideshows on Discord with just `s/i/n`
+
+## Screenshots
+<details>
+  <summary>Click here to see how fxTikTok looks like</summary>
+
+  | ![Preview](https://github.com/okdargy/fxtiktok/assets/76412158/03895ee0-561a-4d8e-9ae7-06a67fcd4272) |
+  |:--:|
+  | Comparing `tiktok.com` vs. `tnktok.com` embeds on Discord |
+</details>
+