:root {
  --bg: #f6f7fb;
  --card: #ffffff;
  --text: #1a1d29;
  --muted: #6b7280;
  --border: #e2e4ea;
  --primary: #2563eb;
  --primary-text: #ffffff;
  --danger: #dc2626;
  --win: #dcfce7;
  --win-border: #16a34a;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  padding-bottom: 76px;
}

.app-header {
  padding: 16px 16px 8px;
  text-align: center;
}
.app-header h1 { margin: 0; font-size: 1.4rem; }

main { max-width: 480px; margin: 0 auto; padding: 8px 16px 24px; }

.view { display: block; }
.view[hidden] { display: none; }

h2 { font-size: 1.15rem; margin: 12px 0; }
h3 { font-size: 1rem; margin: 20px 0 8px; }

label {
  display: flex;
  flex-direction: column;
  gap: 4px;
  font-size: 0.85rem;
  color: var(--muted);
  margin-bottom: 10px;
}

input, select {
  font-size: 1rem;
  padding: 10px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  color: var(--text);
  width: 100%;
}

.field-row {
  display: flex;
  gap: 8px;
}
.field-row label { flex: 1; }

fieldset.item-card {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px;
  margin: 0;
  background: var(--card);
}
fieldset.item-card legend {
  font-weight: 600;
  padding: 0 4px;
}

.compare-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin-bottom: 12px;
}

.location-row {
  margin-bottom: 12px;
}

button {
  font-size: 0.95rem;
  border-radius: 10px;
  border: none;
  padding: 12px;
  cursor: pointer;
}

.primary-btn {
  width: 100%;
  background: var(--primary);
  color: var(--primary-text);
  font-weight: 600;
}
.primary-btn.danger { background: var(--danger); }

.secondary-btn {
  width: 100%;
  background: var(--card);
  border: 1px solid var(--border);
  color: var(--text);
}

#add-item-btn { margin: 4px 0 12px; }

.remove-row {
  display: flex;
  justify-content: flex-end;
  margin-top: 4px;
}
.remove-item-btn {
  background: none;
  border: none;
  color: var(--danger);
  font-size: 0.8rem;
  padding: 4px;
  cursor: pointer;
}

.result-panel {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px;
  margin: 12px 0;
}
.result-panel h4 {
  margin: 12px 0 8px;
  font-size: 0.8rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.02em;
}
.result-panel h4:first-child { margin-top: 0; }
.result-row {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 10px;
  border-radius: 8px;
  margin-bottom: 4px;
}
.result-row-main {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 8px;
}
.result-row.winner {
  background: var(--win);
  border: 1px solid var(--win-border);
}
.result-delta {
  font-size: 0.78rem;
  color: var(--muted);
}
.result-row.winner .result-delta {
  color: var(--win-border);
  font-weight: 600;
}
.add-cart-row-btn {
  width: auto;
  align-self: flex-start;
  padding: 6px 12px;
  font-size: 0.8rem;
}
.warning { color: var(--danger); font-weight: 500; margin: 0 0 12px; }

.attribution, .muted {
  color: var(--muted);
  font-size: 0.78rem;
  margin-top: 8px;
}

.empty-state {
  color: var(--muted);
  text-align: center;
  padding: 24px 8px;
  font-size: 0.9rem;
}

/* Cart */
.cart-row-wrapper {
  position: relative;
  border-radius: 10px;
  overflow: hidden;
  margin-bottom: 8px;
}
.cart-row-delete-bg {
  position: absolute;
  inset: 0;
  background: var(--danger);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  padding-right: 22px;
  font-weight: 600;
  font-size: 0.85rem;
}
.cart-row {
  position: relative;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 12px;
  touch-action: pan-y;
  user-select: none;
}
.cart-row-controls {
  display: flex;
  align-items: center;
  gap: 8px;
}
.qty-btn {
  width: 32px;
  height: 32px;
  padding: 0;
  background: var(--bg);
  border: 1px solid var(--border);
}
.tax-rate-label {
  flex-direction: row;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin: 4px 0 12px;
}
.tax-rate-label input {
  width: 90px;
  flex: none;
}

.cart-summary-block {
  border-top: 1px solid var(--border);
  margin: 8px 0 16px;
  padding-top: 8px;
}
.cart-summary-row {
  display: flex;
  justify-content: space-between;
  padding: 6px 4px;
  font-size: 0.95rem;
}
.cart-summary-row.grand-total {
  font-size: 1.15rem;
  font-weight: 700;
  border-top: 1px solid var(--border);
  margin-top: 4px;
  padding-top: 10px;
}

/* History */
#history-search { margin: 8px 0 12px; }
.history-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 12px;
  margin-bottom: 8px;
}
.history-row-right {
  display: flex;
  align-items: center;
  gap: 10px;
  text-align: right;
}
.delete-btn {
  background: none;
  border: none;
  font-size: 1.1rem;
  padding: 4px;
}
.backup-row {
  display: flex;
  gap: 8px;
  margin-top: 16px;
}
.file-label {
  text-align: center;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Insights */
#insights-item-select { margin-bottom: 12px; }
canvas#insights-chart { max-width: 100%; }
table {
  width: 100%;
  border-collapse: collapse;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  font-size: 0.85rem;
}
th, td {
  text-align: left;
  padding: 8px;
  border-bottom: 1px solid var(--border);
}
th { color: var(--muted); font-weight: 600; }
tr:last-child td { border-bottom: none; }

/* Modal */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  z-index: 100;
}
.modal-box {
  background: var(--card);
  border-radius: 12px;
  padding: 20px;
  max-width: 340px;
  width: 100%;
}
.modal-box p { margin: 0 0 16px; }
.modal-actions {
  display: flex;
  gap: 8px;
}
.modal-actions button { flex: 1; }

/* Bottom nav */
.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  display: flex;
  background: var(--card);
  border-top: 1px solid var(--border);
  padding: 6px 0 max(6px, env(safe-area-inset-bottom));
}
.nav-btn {
  flex: 1;
  background: none;
  border: none;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  font-size: 1.2rem;
  color: var(--muted);
  padding: 6px 0;
}
.nav-btn span { font-size: 0.7rem; }
.nav-btn.active { color: var(--primary); }