"Flash" a lovelace card on entity state?

I’ve placed a tablet on my fridge using magnets and it works wonderfully. I made a lovelace dashboard showing different info like camera feeds, and quick scene toggling etc.

But I would love a way to “light up” / “flash” or otherwise give a lovelace card a border with a striking color when an entity is at a specific state so that its easy to see that something is up from a distance.

My netatmo cameras can detect people, and say for example that a person is seen on one of the cameras, it could be cool to give the picture-entity lovelace card another more striking border color when this happens.

Have a look here and here.

Another idea would be to use the state-switch card.

For example,

type: 'custom:state-switch'
entity: light.alex_bulb
    type: entities
      - entity: light.alex_bulb
    type: entities
    style: |
      ha-card {
        border: 10px solid red;
      - entity: light.alex_bulb