Cannot connect to local datastax cassandra running in docker

I executed this docker command to run instance of datastax cassandra:

docker run -p 9042:9042 -e DS_LICENSE=accept --rm --name my-dse -d datastax/dse-server:6.8.2 -s

Then this to run instance of the datastax studio:

docker run -e DS_LICENSE=accept --link my-dse --name my-studio -p 9091:9091 -d datastax/dse-studio

When I open the browser at http://localhost:9091 to create the connection, I get this error:

All host(s) tried for query failed (tried: / (com.datastax.driver.core.exceptions.TransportException: [/] Cannot connect))

I checked the cassandra instance running in docker and I can connect using cqlsh:

$ docker exec -it my-dse bash -c "cqlsh -u cassandra -p cassandra"
Connected to Test Cluster at
[cqlsh 6.8.0 | DSE 6.8.2 | CQL spec 3.4.5 | DSE protocol v2]
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This is based on the instructions here:

Source: Docker Questions