:root {
  --bg: #f4f6f8;
  --panel: #ffffff;
  --border: #e1e5ea;
  --text: #1f2937;
  --muted: #6b7280;
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --success: #16a34a;
  --warning: #d97706;
  --danger: #dc2626;
  --radius: 8px;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.app-shell { display: flex; min-height: 100vh; }
.sidenav {
  width: 220px;
  background: #111827;
  color: #d1d5db;
  display: flex;
  flex-direction: column;
  padding: 20px 0;
  flex-shrink: 0;
}
.sidenav .brand { color: #fff; font-weight: 700; font-size: 18px; padding: 0 20px 20px; }
.sidenav a { display: block; padding: 12px 20px; color: #d1d5db; }
.sidenav a:hover { background: #1f2937; text-decoration: none; }
.sidenav a.active { background: var(--primary); color: #fff; }
.sidenav a.logout { margin-top: auto; color: #f87171; }

.content { flex: 1; padding: 24px 32px; max-width: 1200px; }
.topbar { display: flex; align-items: center; justify-content: space-between; margin-bottom: 16px; }
.topbar h1 { font-size: 22px; margin: 0; }
.user-chip { color: var(--muted); font-size: 14px; }

.flash { padding: 12px 16px; border-radius: var(--radius); margin-bottom: 16px; }
.flash-success { background: #dcfce7; color: #166534; border: 1px solid #86efac; }
.flash-error { background: #fee2e2; color: #991b1b; border: 1px solid #fca5a5; }
.flash-info { background: #dbeafe; color: #1e40af; border: 1px solid #93c5fd; }

.panel { background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; margin-bottom: 20px; }
.panel h2 { margin-top: 0; font-size: 16px; }

.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 16px; margin-bottom: 24px; }
.card { background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius); padding: 18px; }
.card .label { color: var(--muted); font-size: 13px; text-transform: uppercase; letter-spacing: .04em; }
.card .value { font-size: 26px; font-weight: 700; margin-top: 6px; }

table { width: 100%; border-collapse: collapse; }
th, td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--border); font-size: 14px; }
th { color: var(--muted); font-weight: 600; font-size: 12px; text-transform: uppercase; }
tr:hover td { background: #fafbfc; }
.text-right { text-align: right; }

.btn {
  display: inline-block;
  padding: 9px 16px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: #fff;
  color: var(--text);
  cursor: pointer;
  font-size: 14px;
}
.btn:hover { background: #f3f4f6; text-decoration: none; }
.btn-primary { background: var(--primary); border-color: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-danger { background: var(--danger); border-color: var(--danger); color: #fff; }
.btn-danger:hover { background: #b91c1c; }
.btn-success { background: var(--success); border-color: var(--success); color: #fff; }
.btn-sm { padding: 5px 10px; font-size: 12px; }

.badge { display: inline-block; padding: 3px 10px; border-radius: 999px; font-size: 12px; font-weight: 600; }
.badge-draft { background: #e5e7eb; color: #374151; }
.badge-sent { background: #dbeafe; color: #1e40af; }
.badge-viewed { background: #ede9fe; color: #5b21b6; }
.badge-partially-paid { background: #fef3c7; color: #92400e; }
.badge-paid { background: #dcfce7; color: #166534; }
.badge-overdue { background: #fee2e2; color: #991b1b; }
.badge-cancelled { background: #f3f4f6; color: #6b7280; }
.badge-refunded { background: #fae8ff; color: #86198f; }
.badge-void { background: #f3f4f6; color: #9ca3af; }
.badge-pending { background: #fef3c7; color: #92400e; }
.badge-processing { background: #fef3c7; color: #92400e; }
.badge-completed { background: #dcfce7; color: #166534; }
.badge-failed { background: #fee2e2; color: #991b1b; }

form.stacked label { display: block; margin: 12px 0 4px; font-size: 13px; font-weight: 600; color: #374151; }
form.stacked input[type=text],
form.stacked input[type=email],
form.stacked input[type=tel],
form.stacked input[type=number],
form.stacked input[type=date],
form.stacked input[type=password],
form.stacked select,
form.stacked textarea {
  width: 100%; padding: 9px 10px; border: 1px solid var(--border); border-radius: var(--radius); font-size: 14px;
}
.form-row { display: flex; gap: 16px; }
.form-row > div { flex: 1; }
.actions-bar { margin-top: 20px; display: flex; gap: 10px; }

.login-wrap { display: flex; align-items: center; justify-content: center; min-height: 100vh; background: var(--bg); }
.login-box { background: #fff; padding: 36px; border-radius: var(--radius); border: 1px solid var(--border); width: 360px; }
.login-box h1 { font-size: 20px; margin-top: 0; }
.hint { color: var(--muted); font-size: 12px; margin-top: 16px; }

.items-table input { width: 100%; padding: 6px 8px; border: 1px solid var(--border); border-radius: 6px; }
.items-table td { vertical-align: top; }
.remove-line { color: var(--danger); cursor: pointer; background: none; border: none; font-size: 18px; }

.public-page { background: #f4f6f8; min-height: 100vh; padding: 40px 16px; }
.public-card { max-width: 720px; margin: 0 auto; background: #fff; border-radius: 10px; border: 1px solid var(--border); padding: 32px; }
.public-header { display: flex; justify-content: space-between; align-items: flex-start; border-bottom: 2px solid var(--border); padding-bottom: 20px; margin-bottom: 20px; }
.public-header h2 { margin: 0 0 4px; }
.totals-box { margin-left: auto; width: 280px; }
.totals-box .row { display: flex; justify-content: space-between; padding: 6px 0; }
.totals-box .row.total { border-top: 2px solid var(--border); font-weight: 700; font-size: 16px; padding-top: 10px; }
.pay-methods { display: flex; gap: 12px; margin-top: 20px; flex-wrap: wrap; }
.pay-methods form { flex: 1; min-width: 200px; }
.pay-methods .btn { width: 100%; padding: 14px; font-size: 15px; }
.mock-banner { background: #fffbeb; border: 1px solid #fde68a; color: #92400e; padding: 10px 14px; border-radius: 8px; font-size: 13px; margin-bottom: 16px; }

@media print {
  .sidenav, .topbar, .actions-bar, .no-print { display: none !important; }
  .content { padding: 0; max-width: 100%; }
}