VScode color customization of css bracket not working

I want to change the color of the { symbol in CSS code, but it is not working. See the { in css code below:

In the code above, "{" seems like yellow, even though I applied customization code in settings.json file.

My code is

"editor.tokenColorCustomizations": {
        "[Sonokai]:{
            "textMateRules":[{
                "scope":[
                  "punctuation.section.property-list.begin.bracket.curly.css",
                  "meta.property-list.css",
                  "source.css",
                  "meta.embedded.block.html",
                  "text.html.derivative"
                ],
                "settings": {
                    "foreground":"#D7D8DBE7"
                }
              }
            ]

I found that no matter what color I write in "foreground":"...", it always shows the same color. Applying the color setting to only punctuation.section.property-list.begin.bracket.curly.css scope also didn't work.