* {
  box-sizing: border-box;
}
body,
h1,
h2,
h3,
h4,
p,
a {
  margin: 0;
  font-size: 100%;
  font-weight: normal;
}
body {
  font-family: "Helvetica", "Arial", sans-serif;
  background-color: #eee;
}
.header {
  width: 100vh;
  height: 92vh;
  display: flex;
  margin: 0.2em auto;
  background-color: #eee;
  background-size: cover;
  background-position: center;
  background-image: url(https://pictures.s3.yandex.net/frontend-developer/free-course/cover.jpg);
  text-align: center;
}
.header-title {
  font-size: 140px;
  color: #fff;
  text-transform: uppercase;
  font-weight: 500;
  margin: auto;
}
.overlay {
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  display: flex;
}
.content {
  font-size: 0;
  width: 790px;
  margin: 100px auto 50px;
}
.card {
  padding: 45px 45px 70px 45px;
  width: 350px;
  margin-bottom: 60px;
  margin-right: 90px;
  display: inline-block;
  box-shadow: 4px 4px 5px rgba(24, 171, 239, 0.925);
}
.no-right-margin {
  margin-right: 0;
}
.card-title {
  margin-bottom: 10px;
  font-size: 24px;
  font-weight: 500;
}
.card-text {
  font-size: 16px;
}
.card-image {
  width: 100%;
  margin-bottom: 25px;
}
.footer {
  height: 300px;
  background-color: black;
  display: flex;
}
.footer-author {
  font-size: 24px;
  color: white;
  margin: auto;
}