大转盘设置奖项背景色，设置渐变样式无法生效

[guawazi233]

你当前是什么框架(必填)：react
你使用的是哪个包(必填)：
你当前插件的版本(必填)：0.1.13
当前环境是小程序还是浏览器(选填)：浏览
详细描述你的bug：大转盘设置奖项背景色，设置渐变样式无法生效
问题代码(重要)：代码demo地址：
https://100px.net/playground.html?code=DwEwlgbgBGILwCIC2BPAtAGwK4GMDWKCAfMAPTgREBQVwAzjgE5gAOALtVFDgPYB2dNlBbMAXgFMAkkgDmUOFADeVLlzqMcALigByUoICGbMDlJhZdUiLASAdCz4ydAGhWqA7rDYALbToAsAAwApC5uXGw8LH4AjCE6bgC%2BbrwCQqgAMrgE8lB84u5QWfgoAMIGfBAGdLbFBADq3uLiGAAUOgDEqJjZKC5K4VCeID5%2BAEyBgSwAHmGqUE1gMt5s45Mzc6oARhg8%2BHTaANqKwgYg4I6xU7POUFsG%2BDKMPFh8IH4dABwAbACcOAAzAw6KCJAC6rnm1gkBygh0GXBO90ez1e710GDA%2BQMjDQTzOYHEfDYrSgYwAzP4QOIZLcOgBRACC33JADFWVAQnTWQB2SbsqBxEIASn65hksMO0KksjBoMh8yUdweeCeLzeHy2nxwAFYAWMxRYjtLpDI5YkFfMkSq1WiPuJfuJPgDxIaJcaxDKzfKEUrkarURrdB0tbr9W7JSbZT7FX6bYH0Z0HU6XRGPTYvebLaprSj1YnMdjcfjwESSZEoMxlmxboxxCBbjssOJRbdxZHPaas4MwUlhbR9ExWBwqEA

<div id="my-lucky"></div>

<script>
  const prizeImg = {
    src: '/static/imgs/prize.png',
    width: '40%',
    top: '10%'
  }
  const myLucky = new LuckyCanvas.LuckyWheel('#my-lucky', {
    width: '200px',
    height: '200px',
    blocks: [{ padding: '10px', background: '#869cfa' }],
    prizes: [
      { background: 'linear-gradient( 234deg, #EA63FF 0%, #F700FF 100%)', imgs: [prizeImg] },
      { background: '#b8c5f2', imgs: [prizeImg] },
      { background: '#e9e8fe', imgs: [prizeImg] },
      { background: '#b8c5f2', imgs: [prizeImg] },
      { background: '#e9e8fe', imgs: [prizeImg] },
      { background: 'linear-gradient(to right, red, blue)', imgs: [prizeImg] },
    ]
  })
</script>