body,
 h1,
 h2,
 h3,
 h4,
 p,
 a {
  margin: 0;
  font-weight: normal;
  font-size: 100%;
}

* {
  box-sizing: border-box;
}

body {
  font-family: "Helvetica", "Arial", sans-serif;
}

.header {
  height: 100vh;
  text-align: center;
  background-image: url(https://pictures.s3.yandex.net/frontend-developer/free-course/cover.jpg);
  background-position: center;
  background-size: cover;
  background-color: #eee;
}

.header-title {
  margin: auto;
  font-weight: 500;
  font-size: 140px;
  text-transform: uppercase;
  color: white;
}

.content {
  margin: 100px auto 50px;
  width: 790px;
  font-size: 0;
}

.overlay {
  display: flex;
  width: 100%;
  height: 100%;
  background-color: rgb(0 0 0 / 50%);
}

.card {
  display: inline-block;
  margin-right: 90px;
  margin-bottom: 60px;
  padding: 45px 45px 70px;
  width: 350px;
  box-shadow: 4px 4px 5px rgb(250 50 50 / 40%);
}

.no-right-margin {
  margin-right: 0;
}

.card-title {
  margin-bottom: 10px;
  font-weight: 500;
  font-size: 24px;
}

.card-text {
  font-size: 16px;
}

.card-image {
  margin-bottom: 25px;
  width: 100%;
}

.footer {
  display: flex;
  height: 300px;
  background-color: #000;
}

.footer-author {
  margin: auto;
  font-size: 24px;
  color: #fff;
}