diff --git a/README_zh.md b/README_zh.md
index d611ed5..2c22667 100644
--- a/README_zh.md
+++ b/README_zh.md
@@ -25,7 +25,7 @@
   <img src="https://img.shields.io/badge/Jupyter-F37626?style=for-the-badge&logo=jupyter&logoColor=white" alt="Jupyter" />
   <img src="https://img.shields.io/badge/Doxygen-2C4AA8?style=for-the-badge&logo=doxygen&logoColor=white" alt="Doxygen" /><br>
   <img src="https://img.shields.io/badge/ZeroMQ-990000?style=for-the-badge&logo=mqtt&logoColor=white" alt="ZeroMQ" /><!--no zeromq icon for zmq-->
-  <img src="https://img.shields.io/badge/WebSocket-010101?style=for-the-badge&logo=socket.io&logoColor=white" alt="WebSocket" />
+  <img src="https://img.shields.io/badge/WebSocket-222222?style=for-the-badge&logo=socket.io&logoColor=white" alt="WebSocket" />
 <img src="https://img.shields.io/badge/MQTT-660066?style=for-the-badge&logo=mqtt&logoColor=white" alt="MQTT" />
   <img src="https://img.shields.io/badge/9P-005F8C?style=for-the-badge&logo=mqtt&logoColor=white" alt="9P" /><!--no glenda bunny icon for plan9-->
   <img src="https://img.shields.io/badge/gRPC-244c5e?style=for-the-badge&logo=data:image/svg+xml;base64,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" alt="gRPC" />