:root {
  --bg-dark: #0a0f1a;
  --bg-card: #121a2b;
  --bg-input: #1a2438;
  --accent: #22c55e;
  --accent-hover: #16a34a;
  --accent-dim: rgba(34, 197, 94, 0.15);
  --text: #e2e8f0;
  --text-muted: #94a3b8;
  --border: #1e293b;
  --danger: #ef4444;
  --warning: #f59e0b;
  --info: #3b82f6;
  --success: #22c55e;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  background: var(--bg-dark);
  color: var(--text);
  min-height: 100vh;
  line-height: 1.5;
  position: relative;
  overflow-x: hidden;
}

/* Background with cameras/sensors theme */
.bg-overlay {
  position: fixed;
  inset: 0;
  z-index: -1;
  background: 
    radial-gradient(ellipse at 20% 20%, rgba(34, 197, 94, 0.08) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 80%, rgba(59, 130, 246, 0.06) 0%, transparent 50%),
    linear-gradient(180deg, #0a0f1a 0%, #0d1525 100%);
  background-size: cover;
}

.bg-overlay::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: 
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='80' height='80' viewBox='0 0 80 80'%3E%3Cg fill='none' stroke='%231e293b' stroke-width='0.5' opacity='0.4'%3E%3Ccircle cx='40' cy='40' r='12'/%3E%3Ccircle cx='40' cy='40' r='6'/%3E%3Cpath d='M40 10v8M40 62v8M10 40h8M62 40h8'/%3E%3C/g%3E%3C/svg%3E");
  opacity: 0.5;
}

.bg-overlay::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image: 
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='120' viewBox='0 0 120 120'%3E%3Cg fill='%231e293b' opacity='0.25'%3E%3Cpath d='M60 20c-8 0-15 7-15 15v10h-8c-4 0-8 4-8 8v30c0 4 4 8 8 8h46c4 0 8-4 8-8V53c0-4-4-8-8-8h-8V35c0-8-7-15-15-15zm0 8c4 0 7 3 7 7v10H53V35c0-4 3-7 7-7z'/%3E%3Ccircle cx='60' cy='72' r='6'/%3E%3C/g%3E%3C/svg%3E");
  background-size: 120px 120px;
  opacity: 0.3;
}

.screen {
  display: none;
  min-height: 100vh;
}

.screen.active {
  display: block;
}

/* LOGIN */
#login-screen {
  display: none;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 1rem;
}

#login-screen.active {
  display: flex;
}

.login-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 2.5rem;
  width: 100%;
  max-width: 420px;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
}

.logo {
  text-align: center;
  margin-bottom: 2rem;
}

.logo i {
  font-size: 3rem;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.logo h1 {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--text);
}

.logo p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-top: 0.25rem;
}

.form-group {
  margin-bottom: 1.25rem;
}

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

@media (max-width: 640px) {
  .form-row {
    grid-template-columns: 1fr;
  }
}

.form-group label {
  display: block;
  margin-bottom: 0.4rem;
  font-size: 0.875rem;
  color: var(--text-muted);
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  font-size: 1rem;
  transition: border-color 0.2s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--accent);
}

.lang-select {
  padding: 0.4rem 0.6rem;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text);
  font-size: 0.85rem;
  cursor: pointer;
}

.lang-select:focus {
  outline: none;
  border-color: var(--accent);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.7rem 1.25rem;
  border: none;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.btn-primary {
  background: var(--accent);
  color: #052e16;
}

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

.btn-secondary {
  background: var(--bg-input);
  color: var(--text);
  border: 1px solid var(--border);
}

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

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

.btn-outline:hover {
  color: var(--text);
  border-color: var(--text-muted);
}

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

.btn-sm {
  padding: 0.4rem 0.8rem;
  font-size: 0.85rem;
}

.btn-block {
  width: 100%;
}

.demo-accounts {
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
  font-size: 0.8rem;
  color: var(--text-muted);
}

.demo-accounts code {
  background: var(--bg-input);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  color: var(--accent);
}

/* HEADER */
.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.9rem 1.5rem;
  background: rgba(18, 26, 43, 0.95);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(8px);
}

.header-left {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.header-left i {
  color: var(--accent);
  font-size: 1.4rem;
}

.brand {
  font-weight: 700;
  font-size: 1.1rem;
}

.header-right {
  display: flex;
  align-items: center;
  gap: 1rem;
}

#user-info {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* NAV */
.nav-tabs {
  display: flex;
  gap: 0.25rem;
  padding: 0.75rem 1.5rem;
  background: var(--bg-card);
  border-bottom: 1px solid var(--border);
  overflow-x: auto;
}

.nav-tab {
  padding: 0.6rem 1rem;
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  border-radius: 8px;
  white-space: nowrap;
  transition: all 0.2s;
}

.nav-tab:hover {
  color: var(--text);
  background: var(--bg-input);
}

.nav-tab.active {
  color: var(--accent);
  background: var(--accent-dim);
}

/* MAIN */
.main-content {
  padding: 1.5rem;
  max-width: 1100px;
  margin: 0 auto;
}

.section {
  display: none;
}

.section.active {
  display: block;
}

.section h2 {
  font-size: 1.4rem;
  margin-bottom: 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.section h2 i {
  color: var(--accent);
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem;
}

.card h3 {
  font-size: 1.05rem;
  margin-bottom: 1rem;
  color: var(--text-muted);
}

/* STATS */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem;
  text-align: center;
}

.stat-card .value {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--accent);
}

.stat-card .label {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* TABLE */
.table {
  width: 100%;
  border-collapse: collapse;
}

.table th,
.table td {
  padding: 0.75rem;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.table th {
  color: var(--text-muted);
  font-weight: 500;
  font-size: 0.85rem;
}

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

/* REPORT CARDS */
.report-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem;
  margin-bottom: 1rem;
  transition: border-color 0.2s;
}

.report-card:hover {
  border-color: #334155;
}

.report-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 0.75rem;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.report-meta {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.badge {
  display: inline-block;
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 600;
}

.badge-pending {
  background: rgba(245, 158, 11, 0.2);
  color: var(--warning);
}

.badge-approved {
  background: rgba(34, 197, 94, 0.2);
  color: var(--success);
}

.badge-rejected {
  background: rgba(239, 68, 68, 0.2);
  color: var(--danger);
}

.badge-paid {
  background: rgba(59, 130, 246, 0.2);
  color: var(--info);
}

.report-items {
  margin: 0.75rem 0;
  font-size: 0.9rem;
}

.report-items li {
  margin-bottom: 0.25rem;
  list-style: none;
  padding-left: 0;
}

.report-total {
  font-weight: 700;
  color: var(--accent);
  margin-top: 0.5rem;
}

.report-actions {
  display: flex;
  gap: 0.5rem;
  margin-top: 1rem;
  flex-wrap: wrap;
}

.photo-thumb {
  width: 80px;
  height: 80px;
  object-fit: cover;
  border-radius: 8px;
  margin: 0.25rem;
  cursor: pointer;
  border: 1px solid var(--border);
}

.photo-preview {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.5rem;
}

.work-row {
  display: grid;
  grid-template-columns: 1fr 80px 40px;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
  align-items: center;
}

.work-row select,
.work-row input {
  padding: 0.5rem;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text);
}

.filters {
  display: flex;
  gap: 0.75rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.filters select {
  padding: 0.5rem 0.75rem;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
}

/* MODAL */
.modal {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  z-index: 1000;
  align-items: center;
  justify-content: center;
  padding: 1rem;
}

.modal.active {
  display: flex;
}

.modal-content {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1.5rem;
  max-width: 600px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  position: relative;
}

.modal-close {
  position: absolute;
  top: 1rem;
  right: 1.25rem;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text-muted);
}

.modal-close:hover {
  color: var(--text);
}

.edit-history {
  margin-top: 1rem;
  padding: 0.75rem;
  background: var(--bg-input);
  border-radius: 8px;
  font-size: 0.85rem;
}

.edit-history h4 {
  margin-bottom: 0.5rem;
  color: var(--warning);
}

.edit-item {
  margin-bottom: 0.4rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--border);
}

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

.empty-state {
  text-align: center;
  padding: 2rem;
  color: var(--text-muted);
}

.empty-state i {
  font-size: 2.5rem;
  margin-bottom: 0.75rem;
  opacity: 0.5;
}

/* ========== RESPONSIVE / MOBILE ========== */

/* Tablets and below */
@media (max-width: 768px) {
  .header {
    padding: 0.75rem 1rem;
  }

  .brand {
    font-size: 1rem;
  }

  .nav-tabs {
    padding: 0.5rem 0.75rem;
    gap: 0.2rem;
    -webkit-overflow-scrolling: touch;
  }

  .nav-tab {
    padding: 0.55rem 0.75rem;
    font-size: 0.8rem;
  }

  .nav-tab i {
    margin-right: 0.25rem;
  }

  .main-content {
    padding: 1rem;
  }

  .section h2 {
    font-size: 1.2rem;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 0.75rem;
  }

  .stat-card {
    padding: 1rem;
  }

  .stat-card .value {
    font-size: 1.4rem;
  }

  .stat-card .label {
    font-size: 0.8rem;
  }

  .card {
    padding: 1rem;
  }

  .table th,
  .table td {
    padding: 0.6rem 0.4rem;
    font-size: 0.85rem;
  }

  .report-card {
    padding: 1rem;
  }

  .report-actions {
    flex-direction: column;
  }

  .report-actions .btn {
    width: 100%;
  }

  .modal-content {
    padding: 1.25rem;
    max-height: 85vh;
    border-radius: 12px 12px 0 0;
    margin-top: auto;
  }

  .photo-thumb {
    width: 70px;
    height: 70px;
  }
}

/* Phones */
@media (max-width: 640px) {
  .login-card {
    padding: 1.75rem 1.25rem;
    border-radius: 12px;
  }

  .logo i {
    font-size: 2.5rem;
  }

  .logo h1 {
    font-size: 1.5rem;
  }

  .header {
    flex-direction: column;
    gap: 0.6rem;
    align-items: stretch;
  }

  .header-left,
  .header-right {
    width: 100%;
    justify-content: space-between;
  }

  .header-right {
    flex-wrap: wrap;
  }

  #user-info {
    font-size: 0.85rem;
    flex: 1;
  }

  .nav-tabs {
    padding: 0.4rem 0.5rem;
    position: sticky;
    top: 0;
    z-index: 90;
    background: rgba(18, 26, 43, 0.98);
    backdrop-filter: blur(8px);
  }

  .nav-tab {
    padding: 0.5rem 0.65rem;
    font-size: 0.75rem;
    flex-shrink: 0;
  }

  /* Hide text on very small, keep icons if needed — but keep labels for clarity */
  .nav-tab i {
    display: inline-block;
  }

  .main-content {
    padding: 0.85rem 0.75rem 5rem; /* extra bottom space for sticky nav feel */
  }

  .section h2 {
    font-size: 1.15rem;
    margin-bottom: 1rem;
  }

  .stats-grid {
    grid-template-columns: 1fr 1fr;
    gap: 0.6rem;
  }

  .stat-card .value {
    font-size: 1.25rem;
  }

  .form-group input,
  .form-group select,
  .form-group textarea {
    padding: 0.85rem 0.9rem; /* larger touch targets */
    font-size: 16px; /* prevents iOS zoom on focus */
  }

  .btn {
    padding: 0.85rem 1.1rem;
    font-size: 0.95rem;
    min-height: 44px; /* Apple touch target guideline */
  }

  .btn-sm {
    padding: 0.55rem 0.9rem;
    min-height: 40px;
  }

  .work-row {
    grid-template-columns: 1fr;
    gap: 0.4rem;
  }

  .work-row select,
  .work-row input {
    padding: 0.75rem;
    font-size: 16px;
    width: 100%;
  }

  .work-row .btn-remove-work {
    width: 100%;
    justify-content: center;
  }

  .filters {
    flex-direction: column;
  }

  .filters select {
    width: 100%;
    padding: 0.75rem;
    font-size: 16px;
  }

  .report-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .report-actions .btn {
    width: 100%;
    justify-content: center;
  }

  .photo-thumb {
    width: 64px;
    height: 64px;
  }

  .table {
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }

  .table th,
  .table td {
    white-space: nowrap;
    font-size: 0.8rem;
  }

  .modal {
    padding: 0;
    align-items: flex-end;
  }

  .modal-content {
    max-width: 100%;
    width: 100%;
    border-radius: 16px 16px 0 0;
    max-height: 92vh;
    padding: 1.25rem 1rem 2rem;
  }

  .modal-close {
    top: 0.75rem;
    right: 1rem;
    font-size: 1.75rem;
    padding: 0.25rem;
  }

  .demo-accounts {
    font-size: 0.75rem;
  }

  .demo-accounts code {
    font-size: 0.7rem;
  }
}

/* Very small phones */
@media (max-width: 380px) {
  .stats-grid {
    grid-template-columns: 1fr;
  }

  .nav-tab {
    padding: 0.45rem 0.5rem;
    font-size: 0.7rem;
  }

  .login-card {
    padding: 1.5rem 1rem;
  }
}

/* Improve touch scrolling and prevent pull-to-refresh issues on some browsers */
html {
  -webkit-text-size-adjust: 100%;
}

body {
  -webkit-overflow-scrolling: touch;
}

/* Safe area for notched phones (iPhone X+) */
@supports (padding: max(0px)) {
  .header {
    padding-left: max(1rem, env(safe-area-inset-left));
    padding-right: max(1rem, env(safe-area-inset-right));
  }

  .nav-tabs {
    padding-left: max(0.5rem, env(safe-area-inset-left));
    padding-right: max(0.5rem, env(safe-area-inset-right));
  }

  .main-content {
    padding-left: max(0.75rem, env(safe-area-inset-left));
    padding-right: max(0.75rem, env(safe-area-inset-right));
    padding-bottom: max(5rem, env(safe-area-inset-bottom));
  }

  .modal-content {
    padding-bottom: max(2rem, env(safe-area-inset-bottom));
  }
}

/* Auth tabs */
.auth-tabs {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1.25rem;
}
.auth-tab {
  flex: 1;
  padding: 0.6rem;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-muted);
  cursor: pointer;
  font-weight: 500;
}
.auth-tab.active {
  background: var(--accent-dim);
  color: var(--accent);
  border-color: var(--accent);
}
.auth-error {
  margin-top: 1rem;
  color: var(--danger);
  font-size: 0.9rem;
  text-align: center;
}