修改滚动条样式:

    .topic-list-wrapper {
      padding: 0 1.875rem 0 1.25rem;
      margin-bottom: 6.25rem;
      border: 0.0625rem solid #000;
      max-height: 40.75rem;
      overflow-y: auto;

      &::-webkit-scrollbar{
        width:.25rem;
        height:6.25rem;
      }
      &::-webkit-scrollbar-track{
        background: rgb(239, 239, 239);
        border-radius:.125rem;
      }
      &::-webkit-scrollbar-thumb{
        background: #000;
        border-radius:.625rem; //设置圆角更好看
      }
      
      //还可以设置 hover 属性
      
      }