:root {
  color-scheme: light dark;
  --bg: #f5f6f8;
  --card: #ffffff;
  --text: #1f2328;
  --muted: #667085;
  --border: #d0d5dd;
  --accent: #1677ff;
  --warning-bg: #fff8e1;
  --warning-border: #f0c36d;
  --danger-bg: #fff1f0;
  --danger-border: #ff7875;
  --success: #16a34a;
}

* {
  box-sizing: border-box;
}

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

.hidden {
  display: none !important;
}

.screen {
  max-width: 720px;
  margin: 0 auto;
  padding: 16px;
}

.setup-card {
  max-width: 420px;
  margin: 12vh auto 0;
  padding: 24px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
}

h1 {
  margin: 0 0 8px;
  font-size: 22px;
}

h2 {
  margin: 0 0 16px;
  font-size: 18px;
}

.muted {
  color: var(--muted);
}

label {
  display: block;
  margin: 14px 0 0;
  font-size: 14px;
}

input,
select,
textarea {
  width: 100%;
  margin-top: 6px;
  padding: 10px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  color: var(--text);
  font: inherit;
}

textarea {
  resize: vertical;
}

button {
  padding: 9px 14px;
  border: 0;
  border-radius: 8px;
  background: var(--accent);
  color: #fff;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
}

button.secondary {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.actions {
  display: flex;
  gap: 8px;
}

.tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 12px;
}

.tab {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
}

.tab.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.add-btn {
  width: 100%;
  margin-bottom: 16px;
}

.station-group {
  margin-bottom: 20px;
}

.station-group h2 {
  margin: 0 0 10px;
  font-size: 17px;
}

.card {
  margin-bottom: 10px;
  padding: 14px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 10px;
}

.card.expiring {
  background: var(--warning-bg);
  border-color: var(--warning-border);
}

.card.expired {
  background: var(--danger-bg);
  border-color: var(--danger-border);
}

.card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
}

.pickup-code {
  margin: 0;
  font-size: 28px;
  font-weight: 800;
  letter-spacing: 1px;
}

.card-meta {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.countdown {
  margin: 8px 0 0;
  font-size: 14px;
  font-weight: 600;
}

.card-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

.card-actions button {
  padding: 7px 11px;
  font-size: 13px;
}

.message {
  min-height: 20px;
  color: var(--muted);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.dialog-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  margin-top: 18px;
}

.modal-backdrop {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 24px 16px;
  overflow: auto;
  background: rgba(0, 0, 0, 0.35);
  z-index: 50;
}

.modal-card {
  width: min(560px, calc(100vw - 32px));
  max-height: calc(100vh - 48px);
  overflow: auto;
  padding: 22px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--card);
  color: var(--text);
}

@media (max-width: 480px) {
  .form-row {
    grid-template-columns: 1fr;
  }

  .pickup-code {
    font-size: 24px;
  }
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1117;
    --card: #161b22;
    --text: #e6edf3;
    --muted: #8b949e;
    --border: #30363d;
    --warning-bg: #2b2412;
    --warning-border: #8a6d1f;
    --danger-bg: #2b1515;
    --danger-border: #a44747;
  }
}