JSFiddle - React, Tailwind, and code Playground

HTML

Sans width
<img src="https://phil.pecheperle.be/image/choix-canne2.jpg" alt="Snow">
<br>
width: auto;
<img src="https://phil.pecheperle.be/image/choix-canne2.jpg" alt="Snow" class="vignette-normal">
<br>
width: 100%;
<img src="https://phil.pecheperle.be/image/choix-canne2.jpg" alt="Snow" class="vignette-large">

CSS

.vignette-normal {
  width: auto;
}

.vignette-large {
  width: 100%;
}