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HTML 

              
                <section class="demo-intro">
  <div class="container">
    <h1>An example of hard-to-maintain media queries</h1>
    <p>This is an example to show why we need container queries. <a href="https://utilitybend.com/blog/styling-based-on-container-width-made-possible-with-css-container-queries" target="_blank">Read more on my blog</a>.</p>
  </div>
</section>
<section class="grid container">
  <main class="content">
    <article class="card">
      <img src="https://picsum.photos/800/600?random=1" alt="" />
      <div class="card-body">
        
        <h2>Some rondom title in here</h2>
        <p class="card-description">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Cras convallis sodales erat vel accumsan.</p>
        <a href="">Read more</a>
      </div>
    </article>
    <article class="card">
      <img src="https://picsum.photos/800/600?random=2" alt="" />
      <div class="card-body">
        
        <h2>Some rondom title in here</h2>
        <p class="card-description">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Cras convallis sodales erat vel accumsan.</p>
        <a href="">Read more</a>
      </div>
    </article>
  </main>
  <aside class="sidebar">
    <article class="card">
      <img src="https://picsum.photos/800/600?random=3" alt="" />
      <div class="card-body">
        
        <h2>Some rondom title in here</h2>
        <p class="card-description">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Cras convallis sodales erat vel accumsan.</p>
        <a href="">Read more</a>
      </div>
    </article>
  </aside>
</section>
!

CSS 

              
                /* Basic card styling */
.card {
  margin-bottom: 24px;
  border: 1px solid #444;
  background: rgba(25,35,51);
}

.card-body {
  padding: 15px;
}

/* container magic, make cards change look & feel based by their container width instead of the viewport */

.grid > * {
  contain: layout inline-size style;
}

@media (max-width: 560px) {
  .card {
    display: grid;
    gap: 15px;
    grid-template-columns: 100px 1fr;
    padding: 15px;
    align-items: center;
  }

  .card .card-body {
    padding: 0;
  }
  .card-description {
    display: none;
  }
}

@media (min-width: 700px) and (max-width: 799px) {
  .content .card {
    display: grid;
    gap: 15px;
    grid-template-columns: 200px 1fr;
    padding: 15px;
    align-items: center;
  }

  .content .card .card-body {
    padding: 0;
  }
}

@media (min-width: 800px) {
  .grid {
    display: grid; 
    grid-template-columns: 1fr 1fr;
    width: 100%;
    gap: 24px;
  }
}

@media (min-width: 900px) {
  .grid {
    grid-template-columns: 1fr 400px;
  }
    
  .content .card {
    display: grid;
    gap: 15px;
    grid-template-columns: 200px 1fr;
    padding: 15px;
    align-items: center;
  }

  .content .card .card-body {
    padding: 0;
  }
}

@media (min-width: 900px) and (max-width: 1100px) {
  .content .card .card-description {
    display: none;
  }
}

/* some basic styling (added to the bottom for convenience) */
* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  font-family: 'Lato', sans-serif;
  font-size: 1.2rem;
  line-height: 1.5;
  color: #FEFEFE;
  background: #1f2937;
}

img {
  max-width: 100%;
  margin: 0;
}

h1 {
  margin: 0 0 16px 0;
  font-family: 'Merriweather', serif;
  font-size: 2rem;
}

h2 {
  margin: 0 0 8px 0;
  font-family: 'Merriweather', serif;
  font-size: 1.5rem;
}

p {
  margin: 0 0 24px 0;
}

.demo-intro {
  font-size: 1.5rem;
  background: #111827;
}

.demo-intro p {
  margin: 0;
}

a {
  color: darkorange;
}

.container {
  max-width: 1300px;
  margin: 0 auto;
  padding: 40px 20px;
}
!

JS
!
999px

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