* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
html, body {
  height: 100%;
  width: 100%;
  font-family: -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Helvetica, Segoe UI, Arial, Roboto, 'PingFang SC', 'miui', 'Hiragino Sans GB', 'Microsoft Yahei', sans-serif;
}
#app {
  height: 100%;
  width: 100%;
}