How to use the jss.toCssValue function in jss

function prefixStyle(style) {
    for (const prop in style) {
      const value = style[prop]
      if (prop === 'fallbacks' && Array.isArray(value)) {
        style[prop] = value.map(prefixStyle)
        continue
      }
      let changeProp = false
      const supportedProp = vendor.supportedProperty(prop)
      if (supportedProp && supportedProp !== prop) changeProp = true

      let changeValue = false
      const supportedValue = vendor.supportedValue(supportedProp, toCssValue(value))
      if (supportedValue && supportedValue !== value) changeValue = true

      if (changeProp || changeValue) {
        if (changeProp) delete style[prop]
        style[supportedProp || prop] = supportedValue || value
      }
    }

    return style
  }

function onChangeValue(value, prop) {
    return vendor.supportedValue(prop, toCssValue(value)) || value
  }