Getting custom font to show up on all desktops

Site URL: http://www.mchughsey.com/

Hello!

I'm new to coding and trying to get my custom font to show up on multiple desktops. I feel like I've followed every rule book that exists on this: I have multiple formats uploaded, tried getting code exported from a webfont toolkit, can get it to work on my desktop but only when the custom css window is open. 

I've given up and decided to see if someone can take a look at this for me, or at least guide me towards white's missing in my code. See below:

@font-face {
font-family: '/ISADORA';
src: url('https://static1.squarespace.com/static/5f5ec4e8056eda51fc2a824f/t/5f602db013d90b092e7e4fc8/1600138672905/IsadoraCaps.eot'),
 
url('https://static1.squarespace.com/static/5f5ec4e8056eda51fc2a824f/t/5f602d8daed573278adaffec/1600138637503/isadoracaps-5arv-webfont.woff2'),
  
  url('https://static1.squarespace.com/static/5f5ec4e8056eda51fc2a824f/t/5f602a2b0319e2676f0e7770/1600137771431/isadoracaps-5arv-webfont.woff');
}

h4 {font-family: '/ISADORA';}

Thank you,

Rachel 

Use this code

@font-face {
    font-family: 'ISADORA';
    src: url('https://static1.squarespace.com/static/5f5ec4e8056eda51fc2a824f/t/5f602db013d90b092e7e4fc8/1600138672905/IsadoraCaps.eot'),url('https://static1.squarespace.com/static/5f5ec4e8056eda51fc2a824f/t/5f602d8daed573278adaffec/1600138637503/isadoracaps-5arv-webfont.woff2'),url('https://static1.squarespace.com/static/5f5ec4e8056eda51fc2a824f/t/5f602a2b0319e2676f0e7770/1600137771431/isadoracaps-5arv-webfont.woff');
}

h4 {
    font-family: 'ISADORA'
}