body {
  margin: 0;
  font-family: Arial, sans-serif;
  color: white;
  text-align: center;
  background: url('images/background.jpg') no-repeat center center/cover;
  position: relative;
  min-height: 100vh;
}

body::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.45); /* затемнение */
  z-index: 0;
}

header, main, footer {
  position: relative;
  z-index: 1;
}

.logo {
  max-width: 220px;
  display: block;
  margin: 20px auto;
}

h1 {
  font-size: 2.2em;
  margin: 40px 0 20px;
}

.contacts {
  font-size: 1.1em;
  margin-top: 20px;
}

a {
  color: #FFD700;
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}

footer {
  margin-top: 40px;
  font-size: 0.9em;
  opacity: 0.8;
}