amend the style of README file
diff --git a/README.md b/README.md
index d5eefe9..542c41b 100644
--- a/README.md
+++ b/README.md
@@ -204,7 +204,7 @@
 rocketmq_group_get_latency_by_storetime{cluster="MQCluster",broker="broker-b",topic="DEV_TID_tfq",group="DEV_CID_cfq",} 0.0
 ```
 
-###RocketMQ Client
+### RocketMQ Client
 
 **Metrics details**