body {
  margin: 0;
  font-family: system-ui, Arial, sans-serif;
  background: #f5f6f8;
  color: #1c1f26;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 18px 28px;
  background: #111827;
  color: #fff;
}

.brand {
  font-size: 1.5rem;
  font-weight: 700;
}

.menu {
  display: flex;
  gap: 10px;
}

.tab {
  background: #374151;
  color: #fff;
  border: 0;
  border-radius: 10px;
  padding: 10px 16px;
  cursor: pointer;
}

.tab.active {
  background: #2563eb;
}

.container {
  max-width: 1100px;
  margin: 28px auto;
  padding: 0 20px;
}

.panel {
  display: none;
  background: #fff;
  border-radius: 16px;
  padding: 24px;
  box-shadow: 0 6px 24px rgba(0,0,0,.08);
}

.panel.active {
  display: block;
}

.muted {
  color: #6b7280;
}

textarea {
  width: 100%;
  resize: vertical;
  border-radius: 12px;
  border: 1px solid #d1d5db;
  padding: 14px;
  font: inherit;
  box-sizing: border-box;
}

.actions {
  margin: 18px 0;
  display: flex;
  gap: 10px;
}

button.primary,
button.secondary,
button.danger {
  border: 0;
  border-radius: 10px;
  padding: 10px 16px;
  cursor: pointer;
  font-weight: 600;
}

button.primary { background: #2563eb; color: #fff; }
button.secondary { background: #e5e7eb; color: #111827; }
button.danger { background: #dc2626; color: #fff; }

table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
}

th, td {
  text-align: left;
  padding: 12px;
  border-bottom: 1px solid #e5e7eb;
}

pre {
  background: #111827;
  color: #f9fafb;
  padding: 14px;
  border-radius: 12px;
  overflow: auto;
}