Need help with sensor icon color based on state

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36

this is not a theme. you are declaring a color.
also, if this is not a template sensor ( cant see because you didnt provide the sensor declaration) you should not use the icon: mdi:gate here. Do that in the sensor declaration, just to be methodical. On the other hand, if this is a template sensor, it could be here, and, of course, if you want the icon to change depending in the state of the sensor.

change:

icon_color: if (state === 'CLOSE') return 'rgb(255, 0, 0)'; else return 'rgb(51, 255, 51)';

into

icon_color: <
  if (state === 'CLOSE') return 'rgb(255, 0, 0)';
  return 'rgb(51, 255, 51)';

the else is not necessary, this makes it cleaner and easier to read.

btw, are you sure the state is in capitals? never seen that before. could you post a screenshot of the sensor in the dev tools <> ?