Is HTML text padding supported now?

According to documentation padding is supported for html documents. I’m trying to test it using this payload

{
    "timeline": {
        "background": "#DD0066",
        "tracks": [
            {
                "clips": [
                    {
                        "asset": {
                            "type": "html",
                            "html": "<div>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec molestie risus sed felis maximus, ac placerat eros iaculis. Maecenas dignissim, turpis et aliquam interdum, nibh risus eui</div>",
                            "css": "div { color: #FF0000; font-size:40px; font-family: RFlex-Black; text-align: center; padding: 30px; } ",
                            "height": 517,
                            "width": 950,
                            "background": "#FFFFFF"
                        },
                        "length": 4,
                        "fit": "none",
                        "scale": 1,
                        "offset": {
                            "x": -0.002,
                            "y": 0.006
                        },
                        "position": "center",
                        "start": 0
                    }
                ]
            }
        ]
    },
    "output": {
        "format": "mp4",
        "size": {
            "width": 1080,
            "height": 1920
        },
        "quality": "high",
        "scaleTo": "mobile",
        "fps": 30
    }
}

I tried to change padding: 30px to different values, but cannot see any changes. Am I missing something?