body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  font-family: system-ui, sans-serif;
  background: linear-gradient(145deg, #0f1419, #1a2740);
  color: #e7ecf3;
}
.hero { text-align: center; padding: 2rem; }
h1 { font-size: 2.5rem; margin: 0 0 0.5rem; }
.tagline { color: #8b98a8; margin-bottom: 2rem; }
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  background: #5b8def;
  color: #fff;
  text-decoration: none;
  border-radius: 10px;
  font-weight: 600;
}
.btn:hover { filter: brightness(1.08); }