:root {
  --bg: #f4f6f8;
  --card: #fff;
  --text: #1a1a1a;
  --muted: #5c6670;
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --border: #d8dee4;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Segoe UI", system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
}

.header {
  background: #111827;
  color: #fff;
  padding: 1.25rem 2rem;
}

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

.subtitle {
  margin: 0.25rem 0 0;
  color: #cbd5e1;
  font-size: 0.95rem;
}

.container {
  max-width: 640px;
  margin: 2rem auto;
  padding: 0 1rem;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem;
  box-shadow: 0 8px 24px rgba(15, 23, 42, 0.06);
}

.card h2 {
  margin: 0 0 0.5rem;
  font-size: 1.25rem;
}

.hint {
  margin: 0 0 1.25rem;
  color: var(--muted);
  line-height: 1.5;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  margin-bottom: 1rem;
}

.field span {
  font-size: 0.875rem;
  font-weight: 600;
}

input, select {
  padding: 0.65rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 1rem;
}

.stats {
  background: #f8fafc;
  border: 1px dashed var(--border);
  border-radius: 8px;
  padding: 0.75rem 1rem;
  margin-bottom: 1rem;
  color: var(--muted);
}

.actions {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

button {
  border: none;
  border-radius: 8px;
  padding: 0.7rem 1.1rem;
  font-size: 1rem;
  cursor: pointer;
  background: var(--accent);
  color: #fff;
}

button:hover:not(:disabled) {
  background: var(--accent-hover);
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

button.secondary {
  background: #e2e8f0;
  color: #0f172a;
}

button.secondary:hover:not(:disabled) {
  background: #cbd5e1;
}

.message {
  margin-top: 1rem;
  padding: 0.75rem 1rem;
  border-radius: 8px;
  background: #fef3c7;
  color: #92400e;
}

.message.error {
  background: #fee2e2;
  color: #991b1b;
}

.message.success {
  background: #dcfce7;
  color: #166534;
}