Serve static content from serverless AWS lambda function

We have an express+React typescript app that is executed from a serverless endpoint which is intended to ultimately move to AWS lambda.

The React bundle is served as static content along with its css , js etc files.

React app is hosted inside a single serverless project. The same is exposed from serverless.yml config as a function named static-router :

static-router:
    handler: src/server.handler
    events:
      - http:  ANY / 
      - http:  ANY /{proxy+} 

So, on my local, it works absolutely fine! All the static content along with the index.html are getting served to the browser using serverless-offline

Static content served

However when I push the same to AWS using serverless deploy - all the static content is not getting served. Refer to this link: https://xjfxfyosml.execute-api.ap-south-1.amazonaws.com/dev/

How do I allow serving static content from the Lambda function which were working perfectly on my local?

What is missing here?