How to Change Site Title to Custom Font (Wexley)

Hi,

I am trying to use a custom font on my website which uses the Wexley template. So far I have had some success using the following CSS:

//Add Rustico font//
@font-face {
    font-family: 'Rustico';
       src: url('https://static1.squarespace.com/static/5ceab898c398340001161747/t/5db609070bf50303d1d5a15e/1572210952149/Rustico-Regular.otfhttps://static1.squarespace.com/static/5ceab898c398340001161747/t/5db609070bf50303d1d5a15e/1572210952149/Rustico-Regular.otf');
  }

h1 {font-family: 'Rustico'}
h2 {font-family: 'Rustico'}
h3 {font-family: 'Rustico'}

/* Font Nav */
div#topNav a {
   font-family: 'Rustico' !important;
}

This changes the font of my headers and navigation bar but it does not change the font of the site title. I have tried a few different suggestions from previous questions other people have already asked but none of them seem to work for me. Any suggestions would be really appreciated.

Thanks,

Henry