<div class="img-block">
  <img src="http://epic.spb.ru/hero/hero.jpg" alt="" />
</div>
img {
  width: 100%;
}

@media screen and (max-width: 600px) {
  img {
    display: none;
  }
}

External CSS

  1. http://epic.spb.ru/hero-img.css

External JavaScript

This Pen doesn't use any external JavaScript resources.