Import style using <link> tag and replace {DOMAIN} with the current domain:
HTML
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no" />
<link href="https://fonts.googleapis.com/css?family=Roboto:300,300i,400,400i,700,700i&display=swap" rel="stylesheet">
<link href="https://fonts.googleapis.com/css?family=Titillium+Web:300,400,400i,600,600i&display=swap" rel="stylesheet">
<link href="{DOMAIN}/font/araxxe-glyph/css/araxxe-glyph.css" rel="stylesheet" />
<link href="{DOMAIN}/tikui.css" rel="stylesheet" />
Pug
meta(name='viewport' content='width=device-width, initial-scale=1, shrink-to-fit=no')
link(href='https://fonts.googleapis.com/css?family=Roboto:300,300i,400,400i,700,700i&display=swap' rel='stylesheet')
link(href='https://fonts.googleapis.com/css?family=Titillium+Web:300,400,400i,700,700i&display=swap' rel='stylesheet')
link(href='{DOMAIN}/font/araxxe-glyph/css/araxxe-glyph.css' rel='stylesheet')
link(href='{DOMAIN}/tikui.css' rel='stylesheet')
The Style have an Atomic Design organization.