Is it wrong to use flexboxgrid classes like “row”, “col-1-of-4” in the element with another class

Can I use the first way with classes instead of the second one when I use flexbox-grid and which one is the correct way of doing it, because in a second way “article” is not the flex item and I don’t know how to proceed?

//FIRST WAY <section class="section-features row">         <article class="feature-box col-1-of-2">             <h2 class="heading-secondary">Heading</h2>             <p class="feature-box__text">                 Lorem ipsum dolor sit amet, consectetur             </p>         </article>         <article class="feature-box">             <h2 class="heading-secondary">Heading</h2>             <p class="feature-box__text">                 Lorem ipsum dolor sit amet, consectetur             </p>         </article>     </section>  //SECOND WAY <section class="section-features">         <div class="row">             <div class="col-1-of-2">                 <article class="feature-box">                     <h2 class="heading-secondary">Heading</h2>                     <p class="feature-box__text">                         Lorem ipsum dolor sit amet, consectetur                     </p>                 </article>             </div>             <div class="col-1-of-2">                 <article class="feature-box">                     <h2 class="heading-secondary">Heading</h2>                     <p class="feature-box__text">                         Lorem ipsum dolor sit amet, consectetur                     </p>                 </article>             </div>         </div>     </section>