I created a blog post with three categories: (Digital Marketing Category, Tips & Advice Category, Cryptocurrency Category)

What I want to do is filter it.

For example, if I want to see all articles in the Digital Marketing category, I will click this button to show all Digital Marketing categories and hide other categories.

This is my code sample. The problem is that my filter is not working. where is the problem?

I tried adding JavaScript to make it work, but still doesn't work. where is the problem?

document.addEventListener("DOMContentLoaded", () => {
  "use strict";

  /**
   * Article Category Filter
   */
  const filterButtons = document.querySelectorAll('.blog-filters button');
  const articleCards = document.querySelectorAll('.article-card');

  filterButtons.forEach(button => {
    button.addEventListener('click', () => {
      const selectedCategory = button.getAttribute('data-category');

      articleCards.forEach(card => {
        const cardCategory = card.getAttribute('data-category');

        if (selectedCategory === 'all' || selectedCategory === cardCategory) {
          card.style.display = 'block';
        } else {
          card.style.display = 'none';
        }
      });
    });
  });
}); // this line added by community

<section id="blog" class="blog">
  <div class="row">
    <div class="col-md-8">
      <div class="posts-list">
        <div class="row">
          <div class="col-lg-6 col-md-6 d-md-flex article-card" data-category="digital-marketing-category">
            Blog Card
          </div>
          <!-- Article Card -->

          <div class="col-lg-6 col-md-6 d-md-flex article-card" data-category="tips-and-advice-category">
            Blog Card
          </div>
          <!-- Article Card -->

          <div class="col-lg-6 col-md-6 d-md-flex article-card" data-category="cryptocurrency-category">
            Blog Card
          </div>
          <!-- Article Card -->
        </div>
      </div>
    </div>

    <div class="col-md-4">
      <div class="sidebar">
        <h3 class="sidebar-title">Article Categories</h3>
        <div class="blog-filters">
          <button data-category="filter-all">All</button>
          <button data-category="digital-marketing-category">Digital Marketing</button>
          <button data-category="tips-and-advice-category">Tips & Advice</button>
          <button data-category="cryptocurrency-category">Cryptocurrency</button>
        </div>
      </div>
    </div>
  </div>
</section>