Replace h4 with div to keep headers sequentially-descending order

![image](https://user-images.githubusercontent.com/100967476/163469189-db7cb2b7-39d9-4577-9408-767062b64172.png)
Lighthouse

![image](https://user-images.githubusercontent.com/100967476/163469221-16bcd736-5c40-4fc6-8ccf-c4ff9ec5b2a2.png)

![image](https://user-images.githubusercontent.com/100967476/163469253-8f473433-c21b-44b1-ab92-a0914b8533a4.png)
