ElementUI的MessageBox的按钮置灰且不可点击

	// this.$confirm
 	this.$alert('这是一段内容', '标题名称', {
          confirmButtonText: '确定',
          confirmButtonCLass: 'confirmButton',
          beforeClose: (action,instance,done) => {
            if (action == 'confirm) {
            	return false
          	} else {
          		done()
          	}
        });
      }

.confirmButton {
	background: #ccc !important;
	cursor: not-allowed;
}