public static function fetch_fonts( $sort = 'alpha' ) {
		if ( false !== $font_list = get_site_transient( 'pum_google_fonts_list' ) ) {
			return $font_list;
		}

		$google_api_url = 'https://www.googleapis.com/webfonts/v1/webfonts?key=' . self::$api_key . '&sort=' . $sort;
		$response       = wp_remote_retrieve_body( wp_remote_get( $google_api_url, array( 'sslverify' => false ) ) );

		if ( ! is_wp_error( $response ) ) {
			$data = json_decode( $response, true );
		}

		// Store transient for a long time after fetching from Google to save API key hits.
		$transient_time = self::$api_key == self::$default_api_key ? 8 * WEEK_IN_SECONDS : 1 * WEEK_IN_SECONDS;

		if ( ! empty( $data['errors'] ) || empty( $data['items'] ) ) {
			$data = self::load_backup_fonts();
			// Store transient for short period.
			$transient_time = 1 * DAY_IN_SECONDS;
		}

		$items     = $data['items'];
		$font_list = array();

		if ( count( $items ) ) {
			foreach ( $items as $item ) {
				$font_list[ $item['family'] ] = $item;
			}
		}

		set_site_transient( 'pum_google_fonts_list', $font_list, $transient_time );

		return $font_list;
	}