css 使每行最後一個margin-right無效

<div class="showGenres">
 <div class="ginner">
 <span class="genreTab">流派1</span>
 <span class="genreTab">流派1</span>
 <span class="genreTab">流派1</span>
 </div>
</div>




 .showGenres{
 //width: 742px;
 .ginner{
 width: calc(100% + 26px);
 }
 .genreTab{




 width: 100px;
 line-height: 50px;
 margin-right: 26px
 }
 }