JSFiddle - React, Tailwind, and code Playground

by David Thomas

HTML

<div class="container">

  <div class="col">
    <p class="explication">If an image is present, it can't be wider then 50%</p>
    <div class="card">
      <figure class="card__img">
        <img src="https://via.placeholder.com/600" width="600" height="600">
      </figure>
      <p class="card__txt">Lorem ipsum tempus fugit. Aut rerum nostrum qui adipisci est aut. Est error omnis sit velit.</p>
    </div>
  </div>

  <div class="col">
    <p class="explication">Without image, the text should expand to fill all the available space</p>
    <div class="card">
      <p class="card__txt">Lorem ipsum tempus fugit. Aut rerum nostrum qui adipisci est aut. Est error omnis sit velit.</p>
    </div>
  </div>

</div>

CSS

/* Decoration & miscellaneous */

body {
  font-family: sans;
}

.container {
  display: grid;
  column-gap: 1em;
  grid-template-columns: repeat(auto-fill, 35em);
}

.container+.container {
  margin-top: 2em;
}

.explication {
  color: hsl(230, 100%, 45%);
  font-family: monospace;
  font-style: italic;
}

.card {
  border: 1px solid hsl(230, 100%, 45%);
  min-height: 18em;
}

.card__txt {
  background-color: hsl(0, 0%, 90%);
  margin: 0;
}

figure {
  margin: 0;
}

img {
  max-width: 100%;
  height: auto;
}

/* changes */

.card {
  display: grid;
  grid-gap: 1em;
  grid-template-columns: repeat(2, 1fr);
}

.card__txt {
  grid-column: 1 / span 2;
}

.card__img + .card__txt {
  grid-column: 2;
}