body {
  margin: 60px auto;
  max-width: 800px;
  line-height: 1.6;
  font-size: 18px;
  color: #303030;
  padding: 0 10px;
}

h1, h2, h3 {
  line-height:1.2
}

hr {
  height: 2px;
  background-color: #b6b5b5;
  border: none;
}

ul {
  line-height: 1.1;
}

li::marker {
  color: #636363;
}

.authors {
  color: #575757;
}

.author__link {
  text-decoration: none;
  outline: none;
  padding: 2px 1px 0;
}

.author__link:link {
  color: #2c2c2c;
}

.author__link:visited {
  color: #1d1d1d;
}

.author__link:focus {
  color: #302f2f;
}

.author__link:hover {
  color: #929292;
}

.author__link:active {
  background: white;
  color: #7e7e7e;
}

.back_link:link {
  color: #336797;
  text-decoration: none;
}

.back_link:visited {
  color: #234f77;
}

.back_link:focus {
  color: #467097;
}

.back_link:hover {
  color: #5680a7;
}

.back_link:active {
  background: white;
  color: #5c8bb8;
}

main {
  display: grid;
  grid-template-columns: 1fr repeat(12, minmax(auto, 60px)) 1fr;
  grid-gap: 40px;
  padding: 30px 0;
}

.cards {
  grid-column: 2 / span 12;
  display: grid;
  grid-template-columns: repeat(12, minmax(auto, 60px));
  grid-gap: 20px;
}

.card {
  border-radius: 20px;
  grid-column-end: span 4;
  display: flex;
  flex-direction: column;
  background-color: #f0f0f0;
  cursor: pointer;
  transition: all 0.3s ease 0s;
}

.card:hover {
  transform: translateY(-3px);
}

.card__link {
  text-decoration: none;
  outline: none;
}

.card__link:link {
  color: #1d1d1d;
}

.card__link:visited {
  color: #1d1d1d;
}

.card__link:focus {
  color: #242424;
}

.card__link:hover {
  color: #444444;
}


.card__content {
  padding: 20px;
}

.card__title {
  font-weight: bolder;
  margin-bottom: 5px;
}

.card__title_no_author {
  font-weight: bolder;
  margin: 5px;
}

.card__info {
  display: flex;
  align-self: end;
  align-items: center;
}

.card__bottom {
  margin-left: auto;
  padding: 5px 20px;
  background-color: #f8f8f8;
  border-radius: 20px;
}

@media only screen and (max-width: 1000px) {
  .card {
    grid-column-end: span 6;
  }
}

@media only screen and (max-width: 700px) {
  main {
    grid-gap: 20px;
  }
  .card {
    grid-column-end: span 12;
  }
}

@media only screen and (max-width: 500px) {
  main {
    grid-template-columns: 10px repeat(6, 1fr) 10px;
    grid-gap: 10px;
  }
  .cards {
    grid-column: 2 / span 6;
    grid-template-columns: repeat(6, 1fr);
    grid-gap: 20px;
  }
  .card {
    grid-column-end: span 6;
  }
}