Remote work changed everything - how do you separate work and home?

Been working from home for 18 months and my home office is basically my prison cell. Kids know not to bother me between 9-5 but my brain can't turn off. I'm thinking about emails while playing with my daughter. Then I shut the laptop and I'm thinking about missed deadlines. How do you guys actually separate the two? Wife thinks I'm being lazy when I close the door but I'm literally in back to back meetings all day.