:root {
  --bg: #f5f6f8;
  --card-bg: #ffffff;
  --border: #ddd;
  --border-soft: #eee;
  --text: #111827;
  --muted: #666;
  --nav-bg: #071a46;
  --nav-active: #2b7cff;
  --danger: #ef4444;
  --primary: #2b7cff;
}

body {
  font-family: Arial, "Microsoft YaHei", "PingFang SC", sans-serif;
  margin: 0;
  background: var(--bg);
  color: var(--text);
}

.layout {
  display: grid;
  grid-template-columns: 240px 1fr;
  min-height: 100vh;
}

.side {
  background: var(--nav-bg);
  color: #fff;
  padding: 20px;
}

.side h2 {
  font-size: 20px;
  line-height: 1.3;
  margin: 0 0 28px;
  font-weight: 700;
}

.side a {
  display: block;
  color: #fff;
  text-decoration: none;
  padding: 12px;
  border-radius: 8px;
  margin-bottom: 8px;
  font-size: 16px;
  line-height: 1.4;
}

.side a.active,
.side a:hover {
  background: var(--nav-active);
}

.main {
  padding: 24px;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}

input,
select,
textarea,
button {
  font-size: 14px;
}

.note {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.6;
}

.muted {
  color: var(--muted);
  font-size: 13px;
  line-height: 1.6;
}

.empty {
  color: #777;
  padding: 20px 0;
}

@media (max-width: 980px) {
  .layout {
    grid-template-columns: 1fr;
  }
}

/* mobile-responsive: only affects screens up to 768px */
@media (max-width: 768px) {
  body {
    font-size: 15px;
  }

  .layout {
    display: block;
    min-height: auto;
  }

  .side {
    padding: 14px 12px;
  }

  .side h2 {
    font-size: 18px;
    margin: 0 0 12px;
  }

  .side a {
    display: inline-block;
    font-size: 14px;
    padding: 9px 10px;
    margin: 0 6px 8px 0;
    border-radius: 999px;
  }

  .main {
    padding: 14px;
  }

  .card {
    padding: 14px;
    border-radius: 10px;
    margin-bottom: 12px;
  }

  h2 {
    font-size: 20px;
  }

  h3 {
    font-size: 17px;
  }

  input,
  select,
  textarea,
  button {
    font-size: 16px;
  }

  input,
  select,
  textarea {
    min-height: 42px;
  }

  button,
  .button,
  .primary,
  .refresh-button {
    min-height: 42px;
    padding: 10px 14px;
  }

  .actions,
  .section-actions,
  .dashboard-header {
    flex-direction: column;
    align-items: stretch;
  }

  .actions a,
  .actions button,
  .section-actions button,
  .dashboard-header button {
    width: 100%;
    box-sizing: border-box;
    text-align: center;
  }

  .content-grid,
  .grid-2,
  .grid-3,
  .kpi-grid,
  .form-grid-3,
  .bom-grid {
    grid-template-columns: 1fr !important;
  }

  .wide-2,
  .wide-4 {
    grid-column: span 1 !important;
  }

  .kpi-value {
    font-size: 24px;
  }

  .chart-row {
    grid-template-columns: 88px minmax(0, 1fr) 70px;
    gap: 8px;
    font-size: 13px;
  }

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

  table {
    min-width: 720px;
    font-size: 13px;
  }

  th,
  td {
    padding: 8px;
  }

  .variant-header {
    display: none;
  }

  .variant-row {
    grid-template-columns: 1fr !important;
    gap: 8px;
    padding: 12px 0;
  }

  .receipt-box {
    display: grid;
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .receipt-box input,
  .receipt-box button {
    width: 100%;
  }

  .autocomplete-menu {
    max-height: 220px;
  }

  .loading-box {
    width: calc(100vw - 40px);
    padding: 24px 18px;
  }
}