theme.json

{
    "version": 1,
    "settings": {
        "appearanceTools": true,
        "spacing": {
            "blockGap": true,
            "margin": true,
            "padding": true
        },
        "align": {
            "wide": true,
            "full": true
        },
        "layout": {
            "contentSize": "740px",
            "wideSize": "1300px"
        }
    },
    "styles": {
        "blocks": {
            "core/image": {
                "elements": {
                    "figure": {
                        "maxWidth": "100%",
                        "marginLeft": "auto",
                        "marginRight": "auto"
                    }
                }
            }
        },
        "elements": {
            "link": {
                "typography": {
                    "textDecoration": "none"
                }
            }
        }
    }
}