@font-face {
  font-family: Bertso;
  src: url(../fonts/Avenir-Light.woff);
  font-weight: 300;
}

@font-face {
  font-family: Bertso;
  src: url(../fonts/Avenir-Roman.woff);
  font-weight: 400;
}

@font-face {
  font-family: Bertso;
  src: url(../fonts/Avenir-Black.woff);
  font-weight: 600;
}