hugo-book-theme/assets/_fonts.scss

/* oxygen-300 - latin */
@font-face {
  font-family: 'Oxygen';
  font-style: normal;
  font-weight: 300;
  font-display: swap;
  src: url('fonts/oxygen-v8-latin-300.eot'); /* IE9 Compat Modes */
  src: local('Oxygen Light'), local('Oxygen-Light'),
       url('fonts/oxygen-v8-latin-300.eot?#iefix') format('embedded-opentype'), /* IE6-IE8 */
       url('fonts/oxygen-v8-latin-300.woff2') format('woff2'), /* Super Modern Browsers */
       url('fonts/oxygen-v8-latin-300.woff') format('woff'), /* Modern Browsers */
       url('fonts/oxygen-v8-latin-300.ttf') format('truetype'), /* Safari, Android, iOS */
       url('fonts/oxygen-v8-latin-300.svg#Oxygen') format('svg'); /* Legacy iOS */
}
/* oxygen-regular - latin */
@font-face {
  font-family: 'Oxygen';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url('fonts/oxygen-v8-latin-regular.eot'); /* IE9 Compat Modes */
  src: local('Oxygen Regular'), local('Oxygen-Regular'),
       url('fonts/oxygen-v8-latin-regular.eot?#iefix') format('embedded-opentype'), /* IE6-IE8 */
       url('fonts/oxygen-v8-latin-regular.woff2') format('woff2'), /* Super Modern Browsers */
       url('fonts/oxygen-v8-latin-regular.woff') format('woff'), /* Modern Browsers */
       url('fonts/oxygen-v8-latin-regular.ttf') format('truetype'), /* Safari, Android, iOS */
       url('fonts/oxygen-v8-latin-regular.svg#Oxygen') format('svg'); /* Legacy iOS */
}
/* oxygen-700 - latin */	
@font-face {	
  font-family: 'Oxygen';	
  font-style: normal;	
  font-weight: 700;	
  font-display: swap;	
  src: url('fonts/oxygen-v8-latin-700.eot'); /* IE9 Compat Modes */	
  src: local('Oxygen Bold'), local('Oxygen-Bold'),	
       url('fonts/oxygen-v8-latin-700.eot?#iefix') format('embedded-opentype'), /* IE6-IE8 */	
       url('fonts/oxygen-v8-latin-700.woff2') format('woff2'), /* Super Modern Browsers */	
       url('fonts/oxygen-v8-latin-700.woff') format('woff'), /* Modern Browsers */	
       url('fonts/oxygen-v8-latin-700.ttf') format('truetype'), /* Safari, Android, iOS */	
       url('fonts/oxygen-v8-latin-700.svg#Oxygen') format('svg'); /* Legacy iOS */	
}	
/* oxygen-mono-regular - latin */	
@font-face {	
  font-family: 'Oxygen Mono';	
  font-style: normal;	
  font-weight: 400;	
  font-display: swap;	
  src: url('fonts/oxygen-mono-v6-latin-regular.eot'); /* IE9 Compat Modes */	
  src: local('Oxygen Mono'), local('OxygenMono-Regular'),	
       url('fonts/oxygen-mono-v6-latin-regular.eot?#iefix') format('embedded-opentype'), /* IE6-IE8 */	
       url('fonts/oxygen-mono-v6-latin-regular.woff2') format('woff2'), /* Super Modern Browsers */	
       url('fonts/oxygen-mono-v6-latin-regular.woff') format('woff'), /* Modern Browsers */	
       url('fonts/oxygen-mono-v6-latin-regular.ttf') format('truetype'), /* Safari, Android, iOS */	
       url('fonts/oxygen-mono-v6-latin-regular.svg#OxygenMono') format('svg'); /* Legacy iOS */	
}

body {
  font-family: 'Oxygen', sans-serif;
}

code {
  font-family: 'Oxygen Mono', monospace;
}