* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: radial-gradient(circle at top, #1b1035 0%, #0a0618 70%);
  color: #f1eefc;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.hero {
  text-align: center;
  padding: 4rem 1.5rem 2.5rem;
}

.hero h1 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}

.hero p {
  color: #b6a9e0;
}

main {
  flex: 1;
  max-width: 800px;
  margin: 0 auto;
  padding: 0 1.5rem 3rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  width: 100%;
}

.card {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 12px;
  padding: 1.75rem;
}

.card h2 {
  margin-bottom: 0.75rem;
  color: #c9b8ff;
}

.card p {
  line-height: 1.6;
}

#fact-btn {
  margin-top: 1rem;
  background: #7c5cff;
  color: white;
  border: none;
  padding: 0.7rem 1.4rem;
  border-radius: 8px;
  font-size: 1rem;
  cursor: pointer;
  transition: background 0.2s ease;
}

#fact-btn:hover {
  background: #6a4be0;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.25rem;
}

.planet h3 {
  margin-bottom: 0.5rem;
}

footer {
  text-align: center;
  padding: 1.5rem;
  color: #7a6ea8;
  font-size: 0.9rem;
}