netbox/netbox/project-static/styles/_external.scss

// Entry for all 3rd party library imports that do not rely on Bootstrap or NetBox styles.
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');
@import '@mdi/font/css/materialdesignicons.min.css';
@import 'flatpickr/dist/flatpickr.css';