/* ==========================================
   DESIGN TOKENS — Hitech-inspired Navy/White
   ========================================== */
:root {
  /* Backgrounds */
  --bg-app: #eef1f6;
  --bg-card: #ffffff;
  --bg-input: #ffffff;
  --bg-hover: #f4f7fb;
  --bg-active: #e8edf5;

  /* Text */
  --text-primary: #1a2332;
  --text-secondary: #5a6a7e;
  --text-tertiary: #9aaab8;

  /* Borders */
  --border-color: #dce3ed;
  --border-focus: #1b4fb8;

  /* Navy palette */
  --navy-dark: #112d60;
  --navy-mid: #1b4fb8;
  --navy-light: #2563eb;
  --navy-muted: #3b7dd8;
  --accent: #1b4fb8;
  --accent-hover: #163fa0;
  --accent-light: #dbeafe;
  --accent-subtle: #eff5ff;

  /* Status */
  --danger: #dc2626;
  --danger-hover: #b91c1c;
  --success: #16a34a;
  --warning: #d97706;

  /* Shadows */
  --shadow-xs: 0 1px 2px rgba(17,45,96,0.05);
  --shadow-sm: 0 2px 6px rgba(17,45,96,0.07);
  --shadow-md: 0 6px 18px rgba(17,45,96,0.10);
  --shadow-lg: 0 12px 32px rgba(17,45,96,0.13);

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;

  /* Safe areas */
  --safe-bottom: env(safe-area-inset-bottom, 0px);
  --safe-top: env(safe-area-inset-top, 0px);
}

/* ==========================================
   RESET & BASE
   ========================================== */
* {
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

html, body {
  margin: 0;
  padding: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Inter", Helvetica, Arial, sans-serif;
  background: var(--bg-app);
  color: var(--text-primary);
  font-size: 15px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  min-height: 100vh;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  padding: 0;
  color: inherit;
}

input, textarea {
  font-family: inherit;
  font-size: 15px;
  color: var(--text-primary);
}

/* ==========================================
   HEADER — Navy bar with white navigation
   ========================================== */
.app-header {
  background: var(--navy-dark);
  padding: calc(var(--safe-top) + 10px) 16px 10px;
  border-bottom: none;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 12px rgba(17,45,96,0.22);
}

/* Brand bar sits inside the header on desktop */
.header-inner {
  display: flex;
  align-items: center;
  gap: 16px;
  max-width: 960px;
  margin: 0 auto;
}

.app-brand {
  display: none; /* hidden on small screens */
  color: #ffffff;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: -0.3px;
  white-space: nowrap;
  flex-shrink: 0;
}

.app-brand span {
  color: #60a5fa;
}

/* ==========================================
   SEGMENTED NAVIGATION — white pills on navy
   ========================================== */
.segmented-nav {
  display: flex;
  background: rgba(255,255,255,0.10);
  border-radius: 8px;
  padding: 3px;
  gap: 2px;
  max-width: 400px;
  margin: 0 auto;
  flex: 1;
}

.segment-btn {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 8px 12px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 500;
  color: rgba(255,255,255,0.65);
  background: transparent;
  border: none;
  cursor: pointer;
  transition: all 0.14s ease;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
}

.segment-btn svg {
  flex-shrink: 0;
}

.segment-btn span {
  white-space: nowrap;
}

.segment-btn.active {
  background: #ffffff;
  color: var(--navy-dark);
  font-weight: 600;
  box-shadow: 0 2px 6px rgba(0,0,0,0.15);
}

.segment-btn:not(.active):hover {
  background: rgba(255,255,255,0.15);
  color: rgba(255,255,255,0.90);
}

.segment-btn:active {
  transform: scale(0.96);
  opacity: 0.88;
}

@media (max-width: 380px) {
  .segment-btn {
    padding: 7px 8px;
    font-size: 12px;
    gap: 4px;
  }
  .segment-btn svg {
    width: 13px;
    height: 13px;
  }
  .segmented-nav {
    padding: 2px;
    gap: 1px;
  }
}

@media (min-width: 768px) {
  .header-inner {
    gap: 24px;
  }
  .app-brand {
    display: block;
  }
  .segmented-nav {
    max-width: 360px;
    margin: 0;
  }
}

/* ==========================================
   LAYOUT
   ========================================== */
.app-main {
  padding: 20px 16px;
  padding-bottom: 108px;
  max-width: 960px;
  margin: 0 auto;
}

.page {
  display: none;
  animation: fadeIn 0.18s ease;
}

.page.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(5px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ==========================================
   CARDS
   ========================================== */
.card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 18px;
  margin-bottom: 14px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-color);
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-color);
}

.card-title {
  margin: 0;
  font-size: 14px;
  font-weight: 600;
  color: var(--navy-dark);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* ==========================================
   INVOICE HEADER CARD — accent strip
   ========================================== */
.invoice-header.card {
  background: var(--navy-dark);
  border: none;
  border-radius: var(--radius-md);
  padding: 16px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: var(--shadow-md);
  position: relative;
  overflow: hidden;
}

.invoice-header.card::before {
  content: '';
  position: absolute;
  right: -20px;
  top: -20px;
  width: 100px;
  height: 100px;
  border-radius: 50%;
  background: rgba(255,255,255,0.05);
}

.invoice-header.card::after {
  content: '';
  position: absolute;
  right: 40px;
  top: 10px;
  width: 60px;
  height: 60px;
  border-radius: 50%;
  background: rgba(255,255,255,0.04);
}

.invoice-label {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: rgba(255,255,255,0.55);
}

.invoice-number {
  font-size: 18px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: #ffffff;
  letter-spacing: 0.5px;
}

.item-count {
  font-size: 12px;
  color: var(--text-secondary);
  font-variant-numeric: tabular-nums;
  font-weight: 500;
}

/* ==========================================
   FORMS & INPUTS
   ========================================== */
.form-group {
  margin-bottom: 14px;
}

.form-group:last-child {
  margin-bottom: 0;
}

label {
  display: block;
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 6px;
  letter-spacing: 0.3px;
  text-transform: uppercase;
}

.input {
  width: 100%;
  padding: 10px 12px;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  outline: none;
  transition: border-color 0.18s, box-shadow 0.18s;
  color: var(--text-primary);
  font-size: 14px;
}

.input:focus {
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px rgba(27, 79, 184, 0.10);
}

.input::placeholder {
  color: var(--text-tertiary);
}

textarea.input {
  resize: vertical;
  min-height: 60px;
}

/* ==========================================
   BUTTONS
   ========================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-weight: 600;
  transition: all 0.14s ease;
  user-select: none;
  letter-spacing: 0.2px;
}

.btn:active {
  transform: scale(0.97);
  opacity: 0.88;
}

.btn-primary {
  background: var(--navy-dark);
  color: #ffffff;
  box-shadow: 0 2px 6px rgba(17,45,96,0.25);
}

.btn-primary:hover {
  background: var(--navy-mid);
}

.btn-outline {
  background: var(--bg-card);
  color: var(--navy-mid);
  border: 1.5px solid var(--navy-mid);
}

.btn-outline:hover {
  background: var(--accent-subtle);
}

.btn-secondary {
  background: var(--accent-subtle);
  color: var(--navy-mid);
  border: 1.5px dashed var(--navy-muted);
  font-weight: 500;
}

.btn-secondary:hover {
  background: var(--accent-light);
}

.btn-danger {
  background: var(--danger);
  color: #ffffff;
  box-shadow: 0 2px 6px rgba(220,38,38,0.20);
}

.btn-danger:hover {
  background: var(--danger-hover);
}

.btn-block {
  width: 100%;
  margin-top: 12px;
}

.btn-icon {
  width: 34px;
  height: 34px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  transition: all 0.12s ease;
  border: 1px solid transparent;
}

.btn-icon:hover {
  background: var(--bg-hover);
  border-color: var(--border-color);
  color: var(--navy-mid);
}

.btn-icon:active {
  background: var(--bg-active);
  transform: scale(0.92);
}

/* Edit icon gets blue tint */
.btn-edit-product {
  color: var(--navy-mid);
}

/* Delete icon gets red tint */
.btn-delete-product {
  color: var(--danger);
}

/* ==========================================
   ITEMS & TOTALS
   ========================================== */
.item-row {
  display: grid;
  grid-template-columns: 1fr 60px 82px 34px;
  gap: 8px;
  align-items: center;
  padding: 10px 0;
  border-bottom: 1px solid var(--border-color);
}

.item-row:last-child {
  border-bottom: none;
}

.item-row .input {
  padding: 8px 10px;
  font-size: 13.5px;
}

.item-total {
  font-size: 13px;
  font-weight: 600;
  text-align: right;
  font-variant-numeric: tabular-nums;
  color: var(--navy-mid);
  padding-bottom: 6px;
}

.totals-card {
  background: var(--navy-dark);
  border: none;
  box-shadow: var(--shadow-md);
  border-radius: var(--radius-md);
}

.total-row {
  display: flex;
  justify-content: space-between;
  padding: 6px 0;
  font-size: 13.5px;
  color: rgba(255,255,255,0.60);
  font-variant-numeric: tabular-nums;
}

.total-row.grand-total {
  font-size: 18px;
  font-weight: 700;
  color: #ffffff;
  border-top: 1px solid rgba(255,255,255,0.15);
  margin-top: 8px;
  padding-top: 12px;
}

/* ==========================================
   SEARCH
   ========================================== */
.search-container {
  position: relative;
  margin-bottom: 12px;
}

.search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-tertiary);
  pointer-events: none;
}

.search-input {
  padding-left: 38px;
  padding-right: 38px;
  background: var(--bg-card);
  border-color: var(--border-color);
}

.clear-search-btn {
  position: absolute;
  right: 8px;
  top: 50%;
  transform: translateY(-50%);
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--bg-active);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: background 0.12s;
}

.clear-search-btn:hover {
  background: var(--border-color);
}

.search-meta {
  font-size: 12px;
  color: var(--text-secondary);
  margin-bottom: 12px;
  padding: 0 2px;
  font-variant-numeric: tabular-nums;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.3px;
}

/* ==========================================
   SAVED BILL RECORDS
   ========================================== */
.record-row {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 14px 16px;
  margin-bottom: 8px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: var(--shadow-xs);
  border: 1px solid var(--border-color);
  transition: box-shadow 0.14s ease, border-color 0.14s ease;
  cursor: pointer;
}

.record-row:hover {
  box-shadow: var(--shadow-sm);
  border-color: var(--navy-muted);
}

.record-row:active {
  transform: scale(0.99);
  background: var(--bg-hover);
}

.record-main {
  flex: 1;
  min-width: 0;
}

.record-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 4px;
}

.record-inv {
  font-weight: 700;
  font-size: 13.5px;
  font-variant-numeric: tabular-nums;
  color: var(--navy-mid);
  background: var(--accent-subtle);
  padding: 2px 8px;
  border-radius: 4px;
  letter-spacing: 0.3px;
}

.record-date {
  font-size: 12px;
  color: var(--text-tertiary);
  font-variant-numeric: tabular-nums;
}

.record-customer {
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 2px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  color: var(--text-primary);
}

.record-items-preview {
  font-size: 12px;
  color: var(--text-secondary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.record-total {
  font-weight: 700;
  font-size: 15px;
  font-variant-numeric: tabular-nums;
  color: var(--navy-dark);
  margin-left: 14px;
  white-space: nowrap;
}

/* ==========================================
   PRODUCTS LIST
   ========================================== */
.product-row {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 14px 16px;
  margin-bottom: 8px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: var(--shadow-xs);
  border: 1px solid var(--border-color);
  transition: box-shadow 0.14s ease;
}

.product-row:hover {
  box-shadow: var(--shadow-sm);
  border-color: var(--border-color);
}

.product-info {
  flex: 1;
  min-width: 0;
}

.product-name {
  font-weight: 600;
  font-size: 14.5px;
  margin-bottom: 3px;
  color: var(--text-primary);
}

.product-meta {
  font-size: 12.5px;
  color: var(--text-secondary);
  font-variant-numeric: tabular-nums;
}

.product-meta .product-code {
  display: inline-block;
  background: var(--accent-subtle);
  color: var(--navy-mid);
  padding: 1px 6px;
  border-radius: 3px;
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: 0.4px;
  margin-right: 6px;
}

.product-actions {
  display: flex;
  gap: 4px;
}

.empty-state {
  text-align: center;
  padding: 48px 20px;
  color: var(--text-tertiary);
  font-size: 14px;
}

.empty-state::before {
  content: '';
  display: block;
  width: 40px;
  height: 40px;
  margin: 0 auto 12px;
  border-radius: 50%;
  background: var(--bg-active);
}

/* ==========================================
   ACTION BAR — navy bottom bar
   ========================================== */
.action-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: var(--navy-dark);
  border-top: none;
  padding: 10px 16px calc(10px + var(--safe-bottom));
  display: flex;
  gap: 8px;
  z-index: 100;
  box-shadow: 0 -4px 16px rgba(17,45,96,0.18);
}

.action-bar .btn {
  flex: 1;
  padding: 11px 0;
  font-size: 13px;
}

.action-bar .btn-primary {
  flex: 1.6;
  background: #ffffff;
  color: var(--navy-dark);
  box-shadow: none;
}

.action-bar .btn-primary:hover {
  background: #f0f6ff;
}

.action-bar .btn-outline {
  border-color: rgba(255,255,255,0.25);
  color: rgba(255,255,255,0.85);
  background: rgba(255,255,255,0.08);
}

.action-bar .btn-outline:hover {
  background: rgba(255,255,255,0.14);
  border-color: rgba(255,255,255,0.40);
}

/* ==========================================
   AUTOCOMPLETE
   ========================================== */
.autocomplete-dropdown {
  position: absolute;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  z-index: 1000;
  max-height: 240px;
  overflow-y: auto;
  overscroll-behavior: contain;
}

.ac-item {
  padding: 10px 14px;
  cursor: pointer;
  border-bottom: 1px solid var(--border-color);
  transition: background 0.1s;
}

.ac-item:last-child {
  border-bottom: none;
}

.ac-item:hover,
.ac-item.active {
  background: var(--accent-subtle);
}

.ac-name {
  font-size: 13.5px;
  font-weight: 600;
  color: var(--text-primary);
}

.ac-meta {
  font-size: 12px;
  color: var(--text-secondary);
  font-variant-numeric: tabular-nums;
  margin-top: 1px;
}

/* ==========================================
   MODALS
   ========================================== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(17,45,96,0.30);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  display: flex;
  align-items: flex-end;
  justify-content: center;
  z-index: 2000;
  animation: fadeIn 0.18s ease;
}

@media (min-width: 768px) {
  .modal-overlay {
    align-items: center;
  }
}

.modal {
  background: var(--bg-card);
  width: 100%;
  max-width: 520px;
  max-height: 90vh;
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  display: flex;
  flex-direction: column;
  animation: slideUp 0.24s cubic-bezier(0.16, 1, 0.3, 1);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

@media (min-width: 768px) {
  .modal {
    border-radius: var(--radius-lg);
    max-height: 82vh;
  }
}

@keyframes slideUp {
  from { transform: translateY(100%); }
  to { transform: translateY(0); }
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 18px;
  border-bottom: 1px solid var(--border-color);
  background: var(--navy-dark);
}

.modal-header h2 {
  margin: 0;
  font-size: 15px;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: 0.2px;
}

.btn-close-modal {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: rgba(255,255,255,0.12);
  font-size: 18px;
  line-height: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255,255,255,0.80);
  transition: background 0.12s;
}

.btn-close-modal:hover {
  background: rgba(255,255,255,0.22);
}

.modal-body {
  padding: 18px;
  overflow-y: auto;
  flex: 1;
}

.modal-footer {
  padding: 12px 18px calc(12px + var(--safe-bottom));
  border-top: 1px solid var(--border-color);
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  background: var(--bg-hover);
}

.modal-footer .btn {
  flex: 1;
}

/* ==========================================
   ITEMS TABLE (in modal view)
   ========================================== */
.items-table {
  width: 100%;
  border-collapse: collapse;
  margin: 14px 0;
  font-size: 13.5px;
}

.items-table th,
.items-table td {
  padding: 9px 6px;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

.items-table th {
  font-weight: 600;
  color: var(--text-secondary);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  background: var(--bg-hover);
}

.items-table tr:last-child td {
  border-bottom: none;
}

.items-table .num {
  text-align: right;
  font-variant-numeric: tabular-nums;
}

.items-table .text-right {
  text-align: right;
}

.items-table tfoot td {
  font-weight: 700;
  color: var(--navy-dark);
  background: var(--accent-subtle);
}

.record-details {
  margin-bottom: 14px;
  font-size: 13.5px;
  line-height: 1.6;
  padding: 12px;
  background: var(--bg-hover);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-color);
}

.record-details .text-secondary {
  color: var(--text-secondary);
  font-size: 12px;
}

.record-notes {
  margin-top: 12px;
  padding: 12px;
  background: var(--bg-hover);
  border-radius: var(--radius-sm);
  font-size: 13px;
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
}

/* ==========================================
   TOASTS
   ========================================== */
.toast-container {
  position: fixed;
  top: calc(var(--safe-top) + 68px);
  left: 50%;
  transform: translateX(-50%);
  z-index: 3000;
  display: flex;
  flex-direction: column;
  gap: 8px;
  pointer-events: none;
  width: 90%;
  max-width: 340px;
}

.toast {
  background: var(--navy-dark);
  color: #fff;
  padding: 11px 16px;
  border-radius: var(--radius-sm);
  font-size: 13.5px;
  font-weight: 500;
  text-align: center;
  box-shadow: var(--shadow-md);
  animation: toastIn 0.28s cubic-bezier(0.16, 1, 0.3, 1);
  pointer-events: auto;
}

.toast.success {
  background: var(--success);
}

.toast.error {
  background: var(--danger);
}

@keyframes toastIn {
  from { opacity: 0; transform: translateY(-16px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ==========================================
   UTILITY
   ========================================== */
.hidden {
  display: none !important;
}

/* ==========================================
   DESKTOP LAYOUT ENHANCEMENTS
   ========================================== */
@media (min-width: 768px) {
  .app-main {
    padding: 24px 24px;
    padding-bottom: 90px;
  }

  /* Two column layout for new bill on desktop */
  #page-new-bill {
    display: none;
    grid-template-columns: 1fr 340px;
    gap: 16px;
    align-items: start;
  }

  #page-new-bill.active {
    display: grid;
  }

  /* Left column: invoice + customer + items */
  #page-new-bill > .invoice-header,
  #page-new-bill > .card:nth-child(2),
  #page-new-bill > .card:nth-child(3) {
    grid-column: 1;
  }

  /* Right column: totals + notes */
  #page-new-bill > .totals-card,
  #page-new-bill > .card:last-child {
    grid-column: 2;
    grid-row: 1 / span 3;
    position: sticky;
    top: 74px;
  }

  .action-bar {
    justify-content: center;
    padding-left: 24px;
    padding-right: 24px;
  }

  .action-bar .btn {
    max-width: 160px;
    flex: none;
  }

  .action-bar .btn-primary {
    max-width: 200px;
    flex: none;
  }
}

/* ==========================================
   PRINT STYLES
   ========================================== */
@media print {
  body * {
    visibility: hidden;
  }
  #thermal-print-area,
  #thermal-print-area * {
    visibility: visible;
  }
  #thermal-print-area {
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
  }
  .app-header,
  .segmented-nav,
  .action-bar,
  .modal-overlay,
  .toast-container,
  .autocomplete-dropdown {
    display: none !important;
  }
}