* {
  box-sizing: border-box;
}

body {
  font-family: system-ui, -apple-system, sans-serif;
  margin: 0;
  background: #0f1419;
  color: #e7ecf1;
  line-height: 1.5;
}

header {
  padding: 1.5rem 2rem;
  border-bottom: 1px solid #243044;
}

header h1 {
  margin: 0;
  font-size: 1.5rem;
}

.tagline {
  margin: 0.25rem 0 0;
  color: #8b9cb3;
}

main {
  max-width: 720px;
  margin: 0 auto;
  padding: 2rem;
}

.card {
  background: #171f2b;
  border: 1px solid #243044;
  border-radius: 8px;
  padding: 1.5rem;
  margin-bottom: 1rem;
}

label {
  display: block;
  margin-bottom: 0.75rem;
  font-size: 0.875rem;
  color: #8b9cb3;
}

input,
select,
textarea,
button {
  width: 100%;
  margin-top: 0.25rem;
  padding: 0.5rem 0.75rem;
  border-radius: 6px;
  border: 1px solid #243044;
  background: #0f1419;
  color: #e7ecf1;
}

button {
  cursor: pointer;
  background: #3b82f6;
  border: none;
  font-weight: 600;
  margin-top: 0.5rem;
}

button.secondary {
  background: #243044;
}

.error {
  color: #f87171;
  margin-top: 0.5rem;
}

.success {
  color: #4ade80;
}

.message {
  border-top: 1px solid #243044;
  padding: 0.75rem 0;
}

.message:first-child {
  border-top: none;
}

.mono {
  font-family: ui-monospace, monospace;
  font-size: 0.85rem;
  word-break: break-all;
}

nav {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

nav button {
  width: auto;
}