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

:root {
  --sidebar-bg: #1e2a3a;
  --sidebar-hover: #2a3a4e;
  --sidebar-active: #3a4f6a;
  --primary: #4a90d9;
  --primary-hover: #3a7bc8;
  --success: #27ae60;
  --danger: #e74c3c;
  --warning: #f39c12;
  --gray-50: #f8f9fa;
  --gray-100: #f0f2f5;
  --gray-200: #e2e6ea;
  --gray-300: #ced4da;
  --gray-400: #adb5bd;
  --gray-600: #6c757d;
  --gray-800: #343a40;
  --gray-900: #212529;
  --radius: 6px;
  --shadow: 0 1px 3px rgba(0,0,0,.1);
  --shadow-lg: 0 4px 12px rgba(0,0,0,.12);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--gray-100);
  color: var(--gray-900);
  font-size: 14px;
  line-height: 1.5;
}

.app {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  width: 220px;
  background: var(--sidebar-bg);
  color: #fff;
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  z-index: 100;
}

.logo {
  padding: 20px;
  font-size: 20px;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 10px;
  border-bottom: 1px solid rgba(255,255,255,.1);
}

.logo-icon { font-size: 24px; }

.nav-links {
  list-style: none;
  padding: 10px 0;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 20px;
  color: rgba(255,255,255,.7);
  text-decoration: none;
  transition: all .15s;
  font-size: 14px;
}

.nav-link:hover {
  background: var(--sidebar-hover);
  color: #fff;
}

.nav-link.active {
  background: var(--sidebar-active);
  color: #fff;
  font-weight: 600;
}

.nav-icon { font-size: 16px; width: 20px; text-align: center; }

/* Content */
.content {
  flex: 1;
  margin-left: 220px;
  display: flex;
  flex-direction: column;
}

.top-bar {
  background: #fff;
  padding: 16px 30px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--gray-200);
  position: sticky;
  top: 0;
  z-index: 50;
}

.top-bar h1 {
  font-size: 22px;
  font-weight: 600;
}

/* Timer Widget */
.timer-widget {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--gray-50);
  padding: 8px 16px;
  border-radius: var(--radius);
  border: 1px solid var(--gray-200);
}

#timer-display {
  font-family: "SF Mono", "Consolas", monospace;
  font-size: 20px;
  font-weight: 600;
  min-width: 90px;
}

.timer-widget.running {
  background: #eaf7ef;
  border-color: var(--success);
}

/* Tab content */
.tab-content {
  display: none;
  padding: 24px 30px;
}

.tab-content.active { display: block; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 13px;
  font-weight: 500;
  transition: all .15s;
}

.btn-sm { padding: 5px 10px; font-size: 12px; }
.btn-xs { padding: 3px 8px; font-size: 11px; }

.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-hover); }
.btn-success { background: var(--success); color: #fff; }
.btn-success:hover { background: #219a52; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover { background: #c0392b; }
.btn-warning { background: var(--warning); color: #fff; }
.btn-secondary { background: var(--gray-200); color: var(--gray-800); }
.btn-secondary:hover { background: var(--gray-300); }

/* Tables */
.table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.table th {
  background: var(--gray-50);
  padding: 10px 14px;
  text-align: left;
  font-weight: 600;
  font-size: 12px;
  text-transform: uppercase;
  color: var(--gray-600);
  border-bottom: 2px solid var(--gray-200);
}

.table td {
  padding: 10px 14px;
  border-bottom: 1px solid var(--gray-100);
}

.table tr:hover td { background: var(--gray-50); }

.table .actions {
  display: flex;
  gap: 6px;
}

/* Toolbar */
.toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
  flex-wrap: wrap;
  gap: 12px;
}

.filters {
  display: flex;
  gap: 10px;
  align-items: center;
}

/* Forms */
.form-container {
  background: #fff;
  padding: 20px;
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  margin-bottom: 20px;
  border: 1px solid var(--gray-200);
}

.form-row {
  display: flex;
  gap: 16px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 4px;
  flex: 1;
  min-width: 150px;
}

.form-group label {
  font-size: 12px;
  font-weight: 600;
  color: var(--gray-600);
  text-transform: uppercase;
}

.form-group input,
.form-group select,
.form-group textarea {
  padding: 8px 10px;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  font-size: 14px;
  font-family: inherit;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(74,144,217,.15);
}

.form-actions {
  display: flex;
  gap: 10px;
  margin-top: 6px;
}

/* Stats Grid */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  margin-bottom: 24px;
}

.stat-card {
  background: #fff;
  padding: 20px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.stat-card .stat-label {
  font-size: 12px;
  text-transform: uppercase;
  color: var(--gray-600);
  font-weight: 600;
  margin-bottom: 6px;
}

.stat-card .stat-value {
  font-size: 28px;
  font-weight: 700;
}

.stat-card.accent-blue .stat-value { color: var(--primary); }
.stat-card.accent-green .stat-value { color: var(--success); }
.stat-card.accent-orange .stat-value { color: var(--warning); }
.stat-card.accent-red .stat-value { color: var(--danger); }

/* Dashboard panels */
.dashboard-panels {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.panel {
  background: #fff;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.panel h3 {
  padding: 14px 18px;
  font-size: 15px;
  border-bottom: 1px solid var(--gray-200);
}

/* Status badges */
.badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 12px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
}

.badge-draft { background: var(--gray-200); color: var(--gray-600); }
.badge-sent { background: #d6eaf8; color: #2471a3; }
.badge-paid { background: #d5f5e3; color: #1e8449; }
.badge-overdue { background: #fadbd8; color: #c0392b; }
.badge-active { background: #d5f5e3; color: #1e8449; }
.badge-completed { background: #d6eaf8; color: #2471a3; }
.badge-archived { background: var(--gray-200); color: var(--gray-600); }

/* Invoice Detail */
.invoice-detail-view {
  background: #fff;
  padding: 30px;
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  margin-bottom: 20px;
}

.invoice-header {
  display: flex;
  justify-content: space-between;
  margin-bottom: 24px;
  padding-bottom: 20px;
  border-bottom: 2px solid var(--gray-200);
}

.invoice-header h2 { font-size: 24px; }

.invoice-meta { text-align: right; }
.invoice-meta p { margin: 4px 0; color: var(--gray-600); }

.invoice-line-items { margin: 20px 0; }

.invoice-totals {
  text-align: right;
  margin-top: 20px;
  padding-top: 14px;
  border-top: 2px solid var(--gray-200);
}

.invoice-totals p { margin: 4px 0; font-size: 15px; }
.invoice-totals .grand-total { font-size: 20px; font-weight: 700; }

/* Utility */
.hidden { display: none !important; }
.text-right { text-align: right; }
.text-muted { color: var(--gray-600); }
.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.mt-10 { margin-top: 10px; }
.mb-10 { margin-bottom: 10px; }

/* Auth Screens */
.auth-screen {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--sidebar-bg) 0%, #2a3a4e 100%);
}

.auth-card {
  background: #fff;
  padding: 40px;
  border-radius: 10px;
  box-shadow: 0 8px 30px rgba(0,0,0,.2);
  width: 100%;
  max-width: 420px;
}

.auth-logo {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 24px;
  color: var(--sidebar-bg);
}

.auth-logo .logo-icon { font-size: 30px; }

.auth-card h2 {
  font-size: 20px;
  margin-bottom: 8px;
  text-align: center;
}

.auth-card p {
  text-align: center;
  margin-bottom: 20px;
}

.auth-card .form-group { margin-bottom: 16px; }

.auth-error {
  background: #fde8e8;
  color: var(--danger);
  padding: 10px 14px;
  border-radius: var(--radius);
  font-size: 13px;
  margin-bottom: 16px;
}

.auth-success {
  background: #d5f5e3;
  color: var(--success);
  padding: 10px 14px;
  border-radius: var(--radius);
  font-size: 13px;
  margin-bottom: 16px;
}

.btn-full { width: 100%; justify-content: center; padding: 12px; font-size: 15px; }

/* Top Bar Right */
.top-bar-right {
  display: flex;
  align-items: center;
  gap: 16px;
}

.user-menu {
  display: flex;
  align-items: center;
  gap: 8px;
  padding-left: 16px;
  border-left: 1px solid var(--gray-200);
}

/* Settings Grid */
.settings-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

#settings-info-table td {
  padding: 8px 14px;
}

#settings-info-table td:first-child {
  font-weight: 600;
  color: var(--gray-600);
  width: 200px;
}

@media (max-width: 700px) {
  .settings-grid { grid-template-columns: 1fr; }
}

/* Modal Overlay */
.modal-overlay {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

/* Responsive */
@media (max-width: 900px) {
  .sidebar { width: 60px; }
  .sidebar .logo-text, .sidebar .nav-link span:not(.nav-icon) { display: none; }
  .sidebar .nav-link { justify-content: center; padding: 14px; }
  .content { margin-left: 60px; }
  .dashboard-panels { grid-template-columns: 1fr; }
}

/* Scrollbar */
::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: var(--gray-100); }
::-webkit-scrollbar-thumb { background: var(--gray-300); border-radius: 4px; }

/* Print styles */
@media print {
  body { background: #fff; font-size: 12pt; }
  .sidebar, .top-bar, .toolbar, .form-container,
  .invoice-detail-view .btn { display: none !important; }
  .app { display: block; }
  .content { margin-left: 0; }
  .tab-content { padding: 0; }
  .invoice-detail-view {
    box-shadow: none;
    padding: 0;
    border-radius: 0;
  }
  .table { box-shadow: none; }
  .table th { background: #f5f5f5 !important; -webkit-print-color-adjust: exact; print-color-adjust: exact; }
  .badge { -webkit-print-color-adjust: exact; print-color-adjust: exact; }
  .text-success, .text-danger { -webkit-print-color-adjust: exact; print-color-adjust: exact; }
}