Hello, I would like to change the color of the states (red and green) for other colors depending on the disconnection time that each host has had. I understand that the color is changed in the .less file, but I don’t know how to do that, for example when a host spends more than 30 minutes without connection has its status in yellow and when more than 1 hour has passed its status in red. I have configured the ckeck_interval = 10 minutes, max_check_attemps = 3, and the retry interval = 1 minute.
Does anyone know how to do this? Greetings
I moved your question out of the category tutorials and guides, as it hardly seems like one 
I do not think that you could/should change your state colours with the CSS (as it is only visual) and instead think more in the direction of having a check for them that goes CRITICAL when they are down.
I understand the issue of verification but how could I call or implement the css code in the icinga configuration file (hosts.conf) to change the color after doing the verification?
I insist with the change of colors because it is something that I must comply with and I cannot think of another way to do it.