Hello,

Sorry for the delay.
We will reply you the solution as soon as we resolve it.

Best regards!

Hello,

The Calibri font is not included in fonts list, but you can add it using these steps:
1-Download font files and add them into your font folder. Location: wp-content/themes/specular/font.

2-Add this code into your style.css file:

@font-face {
	font-family: Calibri;  
	src: url(public_html/your-site/wp-content/themes/your-theme/fonts/FontName-Regular.ttf);  
	font-weight: normal;  
}

Replace font url with your current one.

3-Add this code into your custom css box, to set this font for the menu:
nav .menu > li > a {font-family: "Calibri" !important;}

Read this article for more detailed information.
Let us know.

Best regards!