.main {
  background-image: url("https://www.smokie-revival.cz/obrazek/3/img-3321-pozadi-1920px-jpg/");
  background-repeat: no-repeat;
  background-attachment: fixed;
  background-size: cover;
  background-position: center;
}

body:not(#index) .motive {
  display: none;
}

body:not(#index) .header {
  background-color: #004aa7;
  background-image: var(--bs-gradient);
  position: sticky;
}

.header {
  background-color: #004aa7;
  background-image: var(--bs-gradient);
}