mobile.scss

...
@media screen and (max-width: 550px) {
  .page-title {
      font-size: 20px;
      font-size: 2rem;
  }
  .new-post-button-parent {
    text-align: center;
    span {
      display: none !important;
    }
  }
  .post-button {
    padding: 5px;
  }
  .category-item {
    a {
      padding: 5px;
    }
  }
}

@media screen and (max-width: 767px) {
  .single-post-list {
    min-height: 65px;
    max-height: 65px;
    padding: 10px 0;
  }
}
...