docs: update README

Author: ChenZiHong-Gavin

README.md

@@ -11,8 +11,10 @@
 [![documentation](https://img.shields.io/badge/docs-latest-blue)](https://graphgen-cookbook.readthedocs.io/en/latest/)
 [![wechat](https://img.shields.io/badge/wechat-brightgreen?logo=wechat&logoColor=white)](https://cdn.vansin.top/internlm/dou.jpg)
 [![arXiv](https://img.shields.io/badge/Paper-arXiv-white)](https://arxiv.org/abs/2505.20416)
-[![Hugging Face](https://img.shields.io/badge/Paper-on%20HF-blue?logo=huggingface&logoColor=yellow)](https://huggingface.co/papers/2505.20416)
+[![Hugging Face](https://img.shields.io/badge/Paper-on%20HF-white?logo=huggingface&logoColor=yellow)](https://huggingface.co/papers/2505.20416)
 
+[![Hugging Face](https://img.shields.io/badge/Demo-on%20HF-blue?logo=huggingface&logoColor=yellow)](https://huggingface.co/spaces/chenzihong/GraphGen)
+[![OpenXLab](https://img.shields.io/badge/Demo-on%20OpenXLab-blue?logo=openxlab&logoColor=yellow)](https://g-app-center-000704-6802-aerppvq.openxlab.space)
 
 
 GraphGen: Enhancing Supervised Fine-Tuning for LLMs with Knowledge-Driven Synthetic Data Generation