:root {
  color-scheme: light;
  --bg: #f5f6f8;
  --card: #ffffff;
  --text: #111827;
  --muted: #6b7280;
  --line: #e5e7eb;
  --accent: #111827;
  --pill-on: #e8f5ee;
  --pill-on-text: #117a42;
  --pill-off: #f3f4f6;
  --pill-off-text: #6b7280;
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 15px/1.5 -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}
.shell {
  display: grid;
  grid-template-columns: 240px 1fr;
  min-height: 100vh;
}
.sidebar {
  padding: 28px;
  border-right: 1px solid var(--line);
  background: rgba(255,255,255,0.75);
  backdrop-filter: blur(16px);
}
.sidebar nav { display: grid; gap: 10px; margin-top: 24px; }
.sidebar a { color: var(--text); text-decoration: none; }
.content { padding: 28px; display: grid; gap: 20px; }
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 20px;
  box-shadow: 0 6px 20px rgba(17, 24, 39, 0.05);
  padding: 24px;
}
.hero { display: flex; align-items: center; justify-content: space-between; }
.grid { display: grid; gap: 16px; }
.grid.two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid.three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.eyebrow { text-transform: uppercase; letter-spacing: 0.08em; font-size: 12px; color: var(--muted); margin: 0 0 6px; }
.muted { color: var(--muted); }
.pill {
  display: inline-flex;
  align-items: center;
  padding: 6px 10px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
}
.pill.on { background: var(--pill-on); color: var(--pill-on-text); }
.pill.off { background: var(--pill-off); color: var(--pill-off-text); }
.carrier-groups { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 14px; }
.carrier-box { border: 1px solid var(--line); border-radius: 16px; padding: 16px; }
.carrier-box ul, .card ul { padding-left: 18px; }
.carrier-box li { display: flex; justify-content: space-between; gap: 12px; margin: 8px 0; }
.carrier-head { display: flex; justify-content: space-between; align-items: center; }
.preview-form label { display: grid; gap: 6px; }
input {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 11px 12px;
  font: inherit;
}
.button {
  appearance: none;
  border: 0;
  background: var(--accent);
  color: white;
  padding: 12px 16px;
  border-radius: 14px;
  font: inherit;
  cursor: pointer;
  margin-top: 12px;
}
.output {
  white-space: pre-wrap;
  background: #f9fafb;
  border-radius: 16px;
  padding: 14px;
  border: 1px solid var(--line);
  min-height: 140px;
}
.centered {
  max-width: 680px;
  margin: 12vh auto;
}
@media (max-width: 1024px) {
  .shell { grid-template-columns: 1fr; }
  .sidebar { border-right: 0; border-bottom: 1px solid var(--line); }
  .grid.two, .grid.three, .carrier-groups { grid-template-columns: 1fr; }
  .hero { display: grid; gap: 12px; }
}