themes-wordpress/calvin/theme.json

{
    "version": 2,
    "settings": {
        "color": {
            "palette": [
                {
                    "slug": "foreground",
                    "color": "#E2E4E8",
                    "name": "Foreground",
                    "default": "#ffffff"
                },
                {
                    "slug": "background",
                    "color": "#001844",
                    "name": "Background",
                    "default": "#000000"
                }
            ]
        },
        "custom": {
            "color": {
                "foreground": "var(--wp--preset--color--foreground)",
                "background": "var(--wp--preset--color--background)",
                "primary": "var(--wp--preset--color--foreground)",
                "secondary": "var(--wp--preset--color--foreground)",
                "tertiary": "var(--wp--preset--color--background)"
            }
        }
    },
    "styles": {
        "typography": {
			"fontFamily": "var:preset|font-family|roboto"
        }
    }
}