code: function (styles) {
      {
        var serialized = '';
        var delimiter = '';
        for (var styleName in styles) {
          if (!styles.hasOwnProperty(styleName)) {
            continue;
          }
          var styleValue = styles[styleName];
          if (styleValue != null) {
            var isCustomProperty = styleName.indexOf('--') === 0;
            serialized += delimiter + hyphenateStyleName$1(styleName) + ':';
            serialized += dangerousStyleValue_1(styleName, styleValue, isCustomProperty);
  
            delimiter = ';';
          }
        }
        return serialized || null;
      }
    }
docs: This creates a string that is expected to be equivalent to the style
  attribute generated by server-side rendering. It by-passes warnings and
  security checks so it's not safe to use this value for anything other than
  comparison. It is only used in DEV for SSR validation.