Material-ui输入标签需要缩小样式

Question

当前，如果您具有root样式，它将始终覆盖shrink样式或任何其他样式。

 <InputLabel
   htmlFor={this._username}
   classes={{
        animated: classes.labelShrink,
        root: classes.LabelFontSizeSmallScreen
     }}
  >
    Email
   </InputLabel>

labelShrink在哪里

  labelShrink: {
        '@media only screen and (max-width: 600px)': {
            letterSpacing: 1,
            fontWeight: 600,
            fontSize: 18
        }
    },

和LabelFontSizeSmallScreen是

 LabelFontSizeSmallScreen: {
        // Extra small devices
        '@media only screen and (max-width: 600px)': {
            letterSpacing: 1,
            fontWeight: 300,
            fontSize: 16
        }
    },