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

body {
  background: #090d16;
  color: #f1f5f9;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.container {
  max-width: 800px;
  width: 90%;
  padding: 2rem;
  background: #111827;
  border-radius: 16px;
  border: 1px solid #1e293b;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.5);
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2.5rem;
}

.logo {
  font-weight: 800;
  font-size: 1.5rem;
  color: #38bdf8;
}

nav a {
  color: #94a3b8;
  text-decoration: none;
  margin-left: 1.5rem;
  font-size: 0.95rem;
}

nav a:hover {
  color: #38bdf8;
}

main {
  text-align: center;
  padding: 2rem 0;
}

.badge {
  display: inline-block;
  background: rgba(34, 197, 94, 0.15);
  color: #4ade80;
  padding: 0.4rem 1rem;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  border: 1px solid rgba(34, 197, 94, 0.3);
}

h1 {
  font-size: 2.2rem;
  margin-bottom: 1rem;
  line-height: 1.2;
}

p {
  color: #94a3b8;
  font-size: 1.1rem;
  margin-bottom: 2rem;
}

.btn {
  background: linear-gradient(135deg, #0284c7, #2563eb);
  color: #fff;
  border: none;
  padding: 0.8rem 1.8rem;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 15px -3px rgba(37, 99, 235, 0.4);
}

.output {
  margin-top: 1.5rem;
  font-size: 1.1rem;
  font-weight: 600;
  color: #38bdf8;
  min-height: 1.5rem;
}

footer {
  margin-top: 3rem;
  text-align: center;
  color: #64748b;
  font-size: 0.85rem;
  border-top: 1px solid #1e293b;
  padding-top: 1.5rem;
}