diff --git a/docs/index.md b/docs/index.md
index f0550755..598414b4 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -32,7 +32,7 @@ A curated list of awesome references collected since 2018. Microservices archite
 - [roadmap.sh](https://roadmap.sh/) 
 - [API Landscape](https://www.apidays.co/api-landscape)
 - [Stack Overflow Annual Developer Survey](https://insights.stackoverflow.com/survey)
-### Introduction
+## Introduction
 - [From Java EE To Cloud Native. Microservice Architecture. Openshift VS Kubernetes](introduction.md)
 - [Microservices FAQ & Kubernetes Native](faq.md)
 ## Site Reliability Engineering (SRE)