select2/docs/themes/learn2/scss/theme/_fonts.scss

// Import Google Web Fonts
@import url(//fonts.googleapis.com/css?family=Montserrat:400|Muli:300,400|Inconsolata);

$font-family-default:           "Muli", "Helvetica", "Tahoma", "Geneva", "Arial", sans-serif;
$font-family-header:            "Montserrat", "Helvetica", "Tahoma", "Geneva", "Arial", sans-serif;
$font-family-mono:              "Inconsolata", monospace;
$font-family-serif:             "Georgia", "Times", "Times New Roman", serif;