theme.json

{
    "$schema": "https://schemas.wp.org/trunk/theme.json",
    "version": 2,
    "settings": {
        "border": {
            "color": false,
            "style": false,
            "width": false,
            "radius": false
        },
        "appearanceTools": false,
        "layout": {
            "contentSize": "640px",
            "wideSize": "1024px"
        },
        "color": {
            "custom": false,
            "background": false,
            "customDuotone": false,
            "customGradient": false,
            "link": false,
            "palette": [
                {
                    "name": "Black",
                    "slug": "black",
                    "color": "#000000"
                },
                {
                    "name": "White",
                    "slug": "white",
                    "color": "#ffffff"
                }
            ]
        },
        "spacing": {
            "margin": false,
            "padding": false,
            "units": [
                "em",
                "rem",
                "vh",
                "vw",
                "%"
            ]
        },
        "typography": {
            "customFontSize": false,
            "lineHeight": false,
            "dropCap": false,
            "fontFamilies": [
                {
                    "fontFamily": "sans-serif",
                    "name": "Copy",
                    "slug": "copy"
                },
                {
                    "fontFamily": "sans-serif",
                    "name": "Heading",
                    "slug": "heading"
                }
            ],
            "fontSizes": [
                {
                    "name": "S",
                    "size": ".875rem",
                    "slug": "s"
                },
                {
                    "name": "M",
                    "size": "1.25rem",
                    "slug": "m"
                },
                {
                    "name": "L",
                    "size": "1.375rem",
                    "slug": "l"
                },
                {
                    "name": "XL",
                    "size": "3.25rem",
                    "slug": "xl"
                }
            ]
        }
    }
}