lovelace-card-mod: CSS doesn't seem to work when casting Lovelace page to my Google Hub

My Home Assistant version: 2021.6.0

My lovelace configuration method (GUI or yaml): GUI

What I am doing: Casting a Lovelace tab

What I expected to happen: Additional CSS to be rendered

What happened instead: Nothing

Minimal steps to reproduce:

# The least amount of code possible to reproduce my error
        card_mod:
          style: |
            .name {
            font-size: 30px;
            }
            div {
            font-size: 20px;
            }
# End of code

Error messages from the browser console:

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