:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #dbeafe;
  --success: #16a34a;
  --success-light: #dcfce7;
  --warning: #d97706;
  --warning-light: #fef3c7;
  --danger: #dc2626;
  --danger-light: #fee2e2;
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;
  --radius: 8px;
  --shadow: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -2px rgba(0,0,0,0.05);
  --sidebar-width: 240px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; background: var(--gray-50); color: var(--gray-900); font-size: 14px; line-height: 1.5; }
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

/* Layout */
.app-layout { display: flex; min-height: 100vh; }
.sidebar { width: var(--sidebar-width); background: var(--gray-900); color: white; position: fixed; top: 0; left: 0; bottom: 0; overflow-y: auto; z-index: 100; display: flex; flex-direction: column; }
.sidebar-header { padding: 20px; border-bottom: 1px solid var(--gray-700); }
.sidebar-header h1 { font-size: 18px; font-weight: 700; }
.sidebar-header .tenant-select { margin-top: 8px; width: 100%; padding: 6px 8px; background: var(--gray-800); border: 1px solid var(--gray-600); color: white; border-radius: 4px; font-size: 13px; }
.sidebar-nav { flex: 1; padding: 12px 0; }
.nav-section { padding: 8px 20px 4px; font-size: 10px; text-transform: uppercase; letter-spacing: 1px; color: var(--gray-400); font-weight: 600; }
.nav-item { display: flex; align-items: center; padding: 8px 20px; color: var(--gray-300); cursor: pointer; transition: all 0.15s; font-size: 13px; gap: 10px; }
.nav-item:hover { background: var(--gray-800); color: white; }
.nav-item.active { background: var(--primary); color: white; }
.nav-item .icon { width: 20px; text-align: center; font-size: 16px; }
.nav-item .badge { margin-left: auto; background: var(--danger); color: white; font-size: 11px; padding: 1px 6px; border-radius: 10px; }
.sidebar-footer { padding: 12px 20px; border-top: 1px solid var(--gray-700); font-size: 12px; color: var(--gray-400); }
.sidebar-footer .user-info { display: flex; justify-content: space-between; align-items: center; }
.sidebar-footer .logout-btn { background: none; border: none; color: var(--gray-400); cursor: pointer; font-size: 13px; }
.sidebar-footer .logout-btn:hover { color: white; }

.main-content { margin-left: var(--sidebar-width); flex: 1; min-height: 100vh; }
.page-header { background: white; border-bottom: 1px solid var(--gray-200); padding: 16px 24px; display: flex; justify-content: space-between; align-items: center; }
.page-header h2 { font-size: 20px; font-weight: 600; }
.page-header .actions { display: flex; gap: 8px; }
.page-body { padding: 24px; }

/* Login */
.login-page { display: flex; justify-content: center; align-items: center; min-height: 100vh; background: linear-gradient(135deg, var(--gray-900), var(--primary-dark)); }
.login-card { background: white; padding: 40px; border-radius: 12px; width: 400px; box-shadow: var(--shadow-lg); }
.login-card h1 { text-align: center; margin-bottom: 8px; font-size: 24px; }
.login-card p { text-align: center; color: var(--gray-500); margin-bottom: 24px; }

/* Cards */
.card { background: white; border-radius: var(--radius); box-shadow: var(--shadow); border: 1px solid var(--gray-200); }
.card-header { padding: 16px 20px; border-bottom: 1px solid var(--gray-200); display: flex; justify-content: space-between; align-items: center; }
.card-header h3 { font-size: 16px; font-weight: 600; }
.card-body { padding: 20px; }

/* Stats Grid */
.stats-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px; margin-bottom: 24px; }
.stat-card { background: white; border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow); border: 1px solid var(--gray-200); }
.stat-card .label { font-size: 12px; color: var(--gray-500); text-transform: uppercase; letter-spacing: 0.5px; font-weight: 600; }
.stat-card .value { font-size: 24px; font-weight: 700; margin-top: 4px; }
.stat-card .sub { font-size: 12px; color: var(--gray-500); margin-top: 2px; }
.stat-card.success .value { color: var(--success); }
.stat-card.danger .value { color: var(--danger); }
.stat-card.warning .value { color: var(--warning); }
.stat-card.primary .value { color: var(--primary); }

/* Grid */
.grid { display: grid; gap: 24px; }
.grid-2 { grid-template-columns: 1fr 1fr; }
.grid-3 { grid-template-columns: 1fr 1fr 1fr; }
.grid-4 { grid-template-columns: 1fr 1fr 1fr 1fr; }
@media (max-width: 768px) { .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; } }

/* Buttons */
.btn { display: inline-flex; align-items: center; gap: 6px; padding: 8px 16px; border-radius: 6px; font-size: 13px; font-weight: 500; cursor: pointer; border: 1px solid transparent; transition: all 0.15s; white-space: nowrap; }
.btn:hover { transform: translateY(-1px); }
.btn-primary { background: var(--primary); color: white; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-success { background: var(--success); color: white; }
.btn-danger { background: var(--danger); color: white; }
.btn-warning { background: var(--warning); color: white; }
.btn-outline { background: white; border-color: var(--gray-300); color: var(--gray-700); }
.btn-outline:hover { background: var(--gray-50); }
.btn-sm { padding: 4px 10px; font-size: 12px; }
.btn-lg { padding: 12px 24px; font-size: 15px; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }
.btn-group { display: flex; gap: 4px; }
.btn-icon { padding: 6px 8px; }

/* Forms */
.form-group { margin-bottom: 16px; }
.form-group label { display: block; font-size: 13px; font-weight: 500; color: var(--gray-700); margin-bottom: 4px; }
.form-group .hint { font-size: 11px; color: var(--gray-400); margin-top: 2px; }
.form-row { display: grid; gap: 16px; }
.form-row-2 { grid-template-columns: 1fr 1fr; }
.form-row-3 { grid-template-columns: 1fr 1fr 1fr; }
.form-row-4 { grid-template-columns: 1fr 1fr 1fr 1fr; }
input, select, textarea { width: 100%; padding: 8px 12px; border: 1px solid var(--gray-300); border-radius: 6px; font-size: 13px; font-family: inherit; transition: border-color 0.15s; background: white; }
input:focus, select:focus, textarea:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-light); }
textarea { resize: vertical; min-height: 80px; }
.input-sm { padding: 4px 8px; font-size: 12px; }
input[type="checkbox"] { width: auto; margin-right: 6px; }
.form-check { display: flex; align-items: center; gap: 8px; }
.form-check label { margin-bottom: 0; }

/* Tables */
.table-container { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; }
th { background: var(--gray-50); font-size: 12px; font-weight: 600; text-transform: uppercase; letter-spacing: 0.5px; color: var(--gray-500); padding: 10px 12px; text-align: left; border-bottom: 2px solid var(--gray-200); white-space: nowrap; }
td { padding: 10px 12px; border-bottom: 1px solid var(--gray-100); font-size: 13px; }
tr:hover td { background: var(--gray-50); }
tr.clickable { cursor: pointer; }
td.number, th.number { text-align: right; font-variant-numeric: tabular-nums; }

/* Status badges */
.badge { display: inline-block; padding: 2px 8px; border-radius: 12px; font-size: 11px; font-weight: 600; }
.badge-success { background: var(--success-light); color: var(--success); }
.badge-warning { background: var(--warning-light); color: var(--warning); }
.badge-danger { background: var(--danger-light); color: var(--danger); }
.badge-primary { background: var(--primary-light); color: var(--primary); }
.badge-gray { background: var(--gray-100); color: var(--gray-600); }

/* Tabs */
.tabs { display: flex; gap: 0; border-bottom: 2px solid var(--gray-200); margin-bottom: 20px; }
.tab { padding: 10px 20px; font-size: 13px; font-weight: 500; color: var(--gray-500); cursor: pointer; border-bottom: 2px solid transparent; margin-bottom: -2px; transition: all 0.15s; }
.tab:hover { color: var(--gray-700); }
.tab.active { color: var(--primary); border-bottom-color: var(--primary); }

/* Toolbar */
.toolbar { display: flex; gap: 12px; align-items: center; margin-bottom: 16px; flex-wrap: wrap; }
.toolbar .search { width: 300px; }
.toolbar .filter { width: 150px; }
.toolbar .spacer { flex: 1; }

/* Modal */
.modal-overlay { position: fixed; inset: 0; background: rgba(0,0,0,0.5); z-index: 1000; display: flex; justify-content: center; align-items: flex-start; padding-top: 50px; overflow-y: auto; }
.modal { background: white; border-radius: 12px; width: 90%; max-width: 800px; max-height: calc(100vh - 100px); overflow-y: auto; box-shadow: var(--shadow-lg); margin-bottom: 50px; }
.modal-header { padding: 20px 24px; border-bottom: 1px solid var(--gray-200); display: flex; justify-content: space-between; align-items: center; position: sticky; top: 0; background: white; z-index: 1; border-radius: 12px 12px 0 0; }
.modal-header h3 { font-size: 18px; }
.modal-close { background: none; border: none; font-size: 24px; cursor: pointer; color: var(--gray-400); padding: 0 4px; }
.modal-close:hover { color: var(--gray-700); }
.modal-body { padding: 24px; }
.modal-footer { padding: 16px 24px; border-top: 1px solid var(--gray-200); display: flex; justify-content: flex-end; gap: 8px; position: sticky; bottom: 0; background: white; border-radius: 0 0 12px 12px; }
.modal-lg { max-width: 1000px; }

/* Toast */
.toast-container { position: fixed; top: 20px; right: 20px; z-index: 2000; display: flex; flex-direction: column; gap: 8px; }
.toast { padding: 12px 20px; border-radius: 8px; color: white; font-size: 13px; font-weight: 500; box-shadow: var(--shadow-lg); animation: slideIn 0.3s ease; min-width: 250px; display: flex; justify-content: space-between; align-items: center; }
.toast-success { background: var(--success); }
.toast-error { background: var(--danger); }
.toast-warning { background: var(--warning); }
.toast-close { background: none; border: none; color: white; cursor: pointer; font-size: 18px; opacity: 0.7; }

/* Items table (invoice/quote) */
.items-table { margin-top: 12px; }
.items-table table { font-size: 12px; }
.items-table input, .items-table select { font-size: 12px; padding: 4px 6px; }
.items-table .remove-item { background: none; border: none; color: var(--danger); cursor: pointer; font-size: 16px; }
.add-item-btn { margin-top: 8px; }
.totals-row { display: flex; justify-content: flex-end; margin-top: 16px; }
.totals-table { width: 300px; }
.totals-table td { padding: 4px 8px; }
.totals-table .total-row { font-weight: 700; font-size: 16px; border-top: 2px solid var(--gray-800); }

/* Chart (simple CSS charts) */
.bar-chart { display: flex; align-items: flex-end; gap: 4px; height: 150px; padding-top: 8px; }
.bar { flex: 1; background: var(--primary); border-radius: 3px 3px 0 0; min-height: 2px; position: relative; transition: height 0.3s; }
.bar:hover { background: var(--primary-dark); }
.bar .bar-label { position: absolute; bottom: -20px; left: 50%; transform: translateX(-50%); font-size: 10px; color: var(--gray-500); white-space: nowrap; }
.bar .bar-value { position: absolute; top: -18px; left: 50%; transform: translateX(-50%); font-size: 10px; font-weight: 600; white-space: nowrap; }
.bar-expense { background: var(--danger); }
.bar-expense:hover { background: #b91c1c; }

/* Loading */
.loading { display: flex; justify-content: center; padding: 40px; color: var(--gray-400); }
.spinner { width: 24px; height: 24px; border: 3px solid var(--gray-200); border-top-color: var(--primary); border-radius: 50%; animation: spin 0.8s linear infinite; }

/* Empty state */
.empty-state { text-align: center; padding: 60px 20px; color: var(--gray-400); }
.empty-state .icon { font-size: 48px; margin-bottom: 12px; }
.empty-state h3 { font-size: 16px; color: var(--gray-600); margin-bottom: 4px; }

/* Pagination */
.pagination { display: flex; justify-content: space-between; align-items: center; margin-top: 16px; font-size: 13px; color: var(--gray-500); }
.pagination .page-btns { display: flex; gap: 4px; }

/* Report sections */
.report-section { margin-bottom: 24px; }
.report-section h4 { font-size: 14px; font-weight: 600; color: var(--gray-700); margin-bottom: 8px; padding-bottom: 4px; border-bottom: 1px solid var(--gray-200); }
.report-total { font-weight: 700; background: var(--gray-50); }
.report-positive { color: var(--success); }
.report-negative { color: var(--danger); }

/* Import */
.import-area { border: 2px dashed var(--gray-300); border-radius: 12px; padding: 40px; text-align: center; cursor: pointer; transition: all 0.15s; }
.import-area:hover { border-color: var(--primary); background: var(--primary-light); }
.import-area.dragover { border-color: var(--primary); background: var(--primary-light); }

/* Responsive sidebar */
@media (max-width: 768px) {
  .sidebar { transform: translateX(-100%); transition: transform 0.3s; }
  .sidebar.open { transform: translateX(0); }
  .main-content { margin-left: 0; }
}

/* Animations */
@keyframes slideIn { from { transform: translateX(100%); opacity: 0; } to { transform: translateX(0); opacity: 1; } }
@keyframes spin { to { transform: rotate(360deg); } }

/* Print */
@media print {
  .sidebar, .page-header, .toolbar, .pagination { display: none !important; }
  .main-content { margin-left: 0 !important; }
  .page-body { padding: 0 !important; }
}