我想在reactjs中使用grid.css

我想像在普通HTML和CSS中一样在reactjs中使用grid.css

<head>
  <link rel="stylesheet" type="text/css" href="./vendors/css/grid.css">
</head>

我用在这里,它工作正常

<div class="col span-1-of-4 box">
  <ion-icon name="infinite-outline" class="icon-big"></ion-icon>
  <h3>Up to 365 days/year</h3>
  <p>Never cook again! We really mean that. Our subscription plans include up to 365 days/year coverage. You can also choose to order more flexibly if that's your style.</p>
</div>

现在我想在reactjs中使用相同的东西

import grid from './assets/css/Grid.css';
....

return (
     <div className={classes.App}>
     <h1 className={classes.h1}>Your Time is here </h1>
     <img  src={Logo} width="500" height="600" className={`${grid.col} ${grid.span-1-of-2}`}/>
          <button className={`${classes.btn} ${classes.some}`} onClick={this.showDayHandler}> Choose me! </button>
      </div>

但是它给出了这样的错误

./src/App.js   行34:91:“ of”未定义no-undef

搜索关键字以了解有关每个错误的更多信息。

请指导我