#header {
  background-color: #4057c2;
  background-image: url("/images/letter-background.jpg");
  background-size: cover;
  background-position: center;
  background-attachment: scroll;
  height: auto;
  min-height: 100vh;
  box-sizing: border-box;
  gap: 4rem;
  padding: 4rem 2rem;
}

#header .content {
  margin: 0;
}

#header h1 {
  margin-bottom: 1rem;
}

.app-logo {
  display: block;
  width: min(22rem, 100%);
  height: auto;
  margin-left: auto;
}

.app-preview {
  flex: 0 0 auto;
  position: relative;
  box-sizing: border-box;
  width: min(18.5rem, 78vw);
  border: 2px solid rgba(255, 255, 255, 0.8);
  border-radius: 2.2rem;
  background: #1d2356;
  overflow: hidden;
  box-shadow: 0 1.5rem 3rem rgba(20, 27, 79, 0.3);
}

.app-preview img {
  display: block;
  width: 100%;
  height: auto;
}

@media (max-width: 980px) {
  #header {
    flex-direction: column;
    gap: 2rem;
    padding: 3rem 1.5rem;
  }

  #header .content {
    margin: 0;
    text-align: center;
  }

  .app-logo {
    margin: 0 auto;
  }
}