main/parks.json

{
    "type": "category",
    "query": "(way[leisure=park];relation[leisure=park];)",
    "minZoom": 14,
    "feature": {
        "style": {
            "color": "green",
            "fillColor": "green",
            "fillOpacity": 0.2,
            "weight": 2
        }
    }
}