main.css

/**
 * BASIC LAYOUT
 */

*, *:before, *:after {
  box-sizing: border-box;
}

* {
  margin-top: 0;
  margin-bottom: 1rem;
}

body {
  background: #b6dccb;
}

label {
  cursor: pointer;
}

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

a {
  color: #000;
  text-decoration: none;
}

[data-hidden="true"] {
  display: none;
}

.wrapper {
  max-width: 1260px;
  margin: 0 auto;
  padding: 1rem;
  background: #94cbb2;
}

.media__image img {
  width: 100%;
}

.media__body {
  padding: 1rem;
}

.media__body__head {
  display: -webkit-box;
  display: -webkit-flex;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-pack: justify;
  -webkit-justify-content: space-between;
      -ms-flex-pack: justify;
          justify-content: space-between;
  -webkit-box-align: center;
  -webkit-align-items: center;
      -ms-flex-align: center;
          align-items: center;
}

.media__body__link span {
  text-decoration: underline;
}

.media__body__link:before {
  content: '>';
  text-decoration: none;
}

/**
 * HEADER AND NAVIGATION
 */

.masthead {
  display: -webkit-box;
  display: -webkit-flex;
  display: -ms-flexbox;
  display: flex;
  -webkit-flex-wrap: wrap;
      -ms-flex-wrap: wrap;
          flex-wrap: wrap;
  -webkit-box-align: center;
  -webkit-align-items: center;
      -ms-flex-align: center;
          align-items: center;
  -webkit-box-pack: justify;
  -webkit-justify-content: space-between;
      -ms-flex-pack: justify;
          justify-content: space-between;
}

.masthead .logo {
  margin-right: 1rem;
}

.masthead .main-nav a:hover,
.masthead .main-nav a:focus,
.masthead .main-nav a:active,
.masthead .main-nav a.active {
  text-decoration: underline;
}

.masthead .main-nav ul {
  padding: 0;
}

.masthead .main-nav li {
  display: inline-block;
  list-style: none;
}

.masthead .main-nav li:not(:last-child) {
  margin-right: 1rem;
}

/**
 * PRODUCT FILTERS
 */

.product-filters > * {
  display: block;
  width: 100%;
}

@media all and (min-width: 28em) {
  .product-filters > * {
    display: inline-block;
    width: auto;
  }
}

.pill {
  padding: 0.5rem 1rem;
  border-radius: 1rem;
  background: #666;
  color: #fff;
}

.pill:not(:last-child) {
  margin-right: 1rem;
}

.pill--small {
  font-size: .75em;
  padding: 0.25rem 0.5rem;
}

.pill--red {
  background: #f00000;
}

.pill--green {
  background: #008c00;
}

.pill--orange {
  background: #f07800;
}

/**
 * PRODUCT CARDS
 */

.product-cards {
  display: -webkit-box;
  display: -webkit-flex;
  display: -ms-flexbox;
  display: flex;
  -webkit-flex-wrap: wrap;
      -ms-flex-wrap: wrap;
          flex-wrap: wrap;
  margin-right: -1rem;
}

.product-cards .media {
  background: #fff;
  margin-bottom: 1rem;
}

.product-cards .media:not(:last-child) {
  margin-right: 1rem;
}

@media all and (min-width: 35em) {
  .product-cards .media {
    width: calc(50% - 1rem);
  }
}

@media all and (min-width: 50em) {
  .product-cards .media {
    width: calc(33.333% - 1rem);
  }
}

@media all and (min-width: 75em) {
  .product-cards .media {
    width: calc(25% - 1rem);
  }
}