/* ===== General ===== */
body {
  font-family: Arial, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  margin: 0;
  background: #f4f6f8;
  color: #333;
  line-height: 1.55;
}

/* ===== Header ===== */
header {
  background: #00695c;
  color: white;
  padding: 18px 15px;
  text-align: center;
  box-shadow: 0 2px 5px rgba(0,0,0,0.08);
}

header h1 { margin: 0; font-size: 22px; }

.header-actions { margin-top: 8px; display:flex; gap:8px; justify-content:center; flex-wrap:wrap; }

nav { margin-top: 8px; }
nav a {
  margin: 0 10px;
  color: white;
  text-decoration: none;
  font-weight: bold;
}

/* ===== Controls + Search ===== */
.controls { display:flex; justify-content:space-between; gap:12px; padding:16px; align-items:center; flex-wrap:wrap; }
.search-box { display:flex; gap:8px; align-items:center; flex-wrap:wrap; }
.search-box input { padding:8px 10px; border-radius:6px; border:1px solid #ccc; min-width:240px; }
.search-box select { padding:8px 10px; border-radius:6px; border:1px solid #ccc; }

/* ===== Cards ===== */
.cards {
  display: flex;
  justify-content: space-around;
  flex-wrap: wrap;
  margin: 20px;
  gap: 20px;
}
.card {
  background: white;
  padding: 18px;
  border-radius: 12px;
  width: 40%;
  min-width: 240px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.06);
  text-align: center;
}

/* ===== Invoices List ===== */
.invoices {
  margin: 20px;
  background: white;
  padding: 18px;
  border-radius: 12px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.06);
}
#invoiceList, #customerList { list-style: none; padding: 0; margin: 0; }
#invoiceList li, #customerList li {
  background: #fbfbfb;
  padding: 12px;
  margin-bottom: 10px;
  border-radius: 8px;
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap: 12px;
  border:1px solid #f0f0f0;
}
#invoiceList li strong { margin-right: 8px; }

/* ===== Form ===== */
.form-container, form {
  margin: 20px auto;
  padding: 18px;
  max-width: 480px;
  background: white;
  border-radius: 12px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.06);
}
form { display:flex; flex-direction:column; gap:8px; }
label { font-weight:700; margin-top:6px; }
input, select { padding:10px; border-radius:6px; border:1px solid #ccc; font-size:14px; }

/* ===== Buttons ===== */
button, .btn {
  padding: 9px 12px;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  font-weight: 600;
  transition: transform .12s ease, opacity .12s ease;
}
button:hover, .btn:hover { transform: translateY(-1px); }

.btn-green { background:#00695c; color:#fff; }
.btn-blue { background:#1565c0; color:#fff; }
.btn-red { background:#c62828; color:#fff; }

.btn:disabled { background:#cfcfcf; cursor:not-allowed; color:#666; }

/* small button group spacing inside list items */
#invoiceList li div, #customerList li div { display:flex; gap:8px; align-items:center; }

/* ===== Invoice view styles ===== */
.invoice-container {
  max-width: 780px;
  margin: 30px auto;
  padding: 22px;
  background: #fff;
  border-radius: 8px;
  box-shadow: 0 3px 10px rgba(0,0,0,0.06);
}
.invoice-header {
  text-align: center;
  margin-bottom: 18px;
  border-bottom: 2px solid #eee;
  padding-bottom: 12px;
}
.invoice-header h2 { margin:0; color:#00695c; font-size:24px; }
.invoice-header p { margin:6px 0; color:#555; font-size:14px; }
.invoice-header h3 { margin-top:10px; color:#333; }

.invoice-details { margin: 16px 0; }
.invoice-details p { margin:6px 0; }

.invoice-table { width:100%; border-collapse: collapse; margin-top:12px; }
.invoice-table th, .invoice-table td { border:1px solid #ddd; padding:12px; text-align:left; }
.invoice-table th { background:#f4f6f8; font-weight:700; }

/* charts */
.chart-box { background:white; padding:16px; margin:20px; border-radius:10px; box-shadow:0 2px 6px rgba(0,0,0,0.05); }

/* overdue badge */
.badge-overdue { background:#c62828; color:#fff; padding:4px 8px; border-radius:6px; font-size:12px; margin-left:8px; }

/* print styles - hide header/nav/buttons and page chrome */
@media print {
  header, nav, .header-actions, .controls, .invoice-actions, .quick-actions, button { display:none !important; }
  body { background: #fff; }
  .invoice-container { box-shadow:none; border:none; margin:0; padding:0; }
  .chart-box, .cards, .invoices, .form-container { display:none; }
  main, .invoice-container { width:100%; }
}

/* responsive */
@media (max-width: 900px) {
  .cards { flex-direction:column; align-items:center; }
  .card { width:90%; }
  .controls { flex-direction:column; align-items:flex-start; gap:10px; }
  #invoiceList li { flex-direction:column; align-items:flex-start; }
}

/* Payment history formatting */
#invoiceDetails ul {
  list-style: none;
  padding-left: 0;
}
#invoiceDetails ul li {
  margin-bottom: 6px;
  padding: 6px;
  background: #f9f9f9;
  border-radius: 5px;
}
#invoiceDetails ul li em {
  color: #c62828;
  margin-left: 5px;
  font-size: 13px;
}

/* Analytics charts */
.analytics-chart {
  max-width: 400px;
  margin: 20px auto;
}

.analytics-chart canvas {
  max-height: 250px !important;
}

/* Analytics layout */
.chart-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: 20px;
  margin: 20px;
}

.analytics-chart {
  max-width: 500px;
  margin: 0 auto;
}

.analytics-chart canvas {
  max-height: 250px !important;
}

.download-section {
  text-align: center;
  margin: 30px 0;
}

.download-section .btn {
  background: #00695c;
  padding: 12px 20px;
  font-size: 16px;
  border-radius: 8px;
}

.download-section .btn:hover {
  background: #004d40;
}