body.screen {
  background: radial-gradient(circle at 30% 30%, #222, #000);
  color: #fff;
  font-family: -apple-system, BlinkMacSystemFont, 'Poppins', sans-serif;
  text-align: center;
  min-height: 100vh;
  margin: 0;
  padding: 30px 16px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

h1 { margin-bottom: 8px; }
h2 { margin-top: 0; color: #ccc; }

.btn {
  padding: 14px;
  border-radius: 10px;
  color: white;
  text-decoration: none;
  background: linear-gradient(135deg, #e91e63, #9c27b0);
  margin: 8px 0;
  font-weight: bold;
  display: block;
}

.back {
  position: fixed;
  top: 12px;
  left: 12px;
  background: rgba(0,0,0,.4);
  color: white;
  padding: 6px 10px;
  border-radius: 8px;
  text-decoration: none;
}