:root {
      --bg: #f3f5f8;
      --panel: #ffffff;
      --border: #d7dce4;
      --text: #20242a;
      --muted: #667085;
      --primary: #155eef;
      --primary-hover: #004ee0;
      --success: #217346;
      --danger: #b42318;
      --warning: #9a6700;
      --soft: #f8fafc;
    }

    * {
      box-sizing: border-box;
    }

    body {
      margin: 0;
      padding: 14px;
      background: var(--bg);
      color: var(--text);
      font-family: Verdana, Arial, sans-serif;
    }

    .app {
      max-width: 1500px;
      margin: 0 auto;
    }

    .header {
      margin-bottom: 12px;
      padding: 14px 16px;
      border: 1px solid var(--border);
      border-radius: 10px;
      background: var(--panel);
    }

    .header h1 {
      margin: 0;
      font-size: 19px;
    }

    .header p {
      margin: 6px 0 0;
      color: var(--muted);
      font-size: 12px;
    }

    .layout {
      display: grid;
      grid-template-columns: 390px minmax(0, 1fr);
      gap: 12px;
    }

    .panel {
      border: 1px solid var(--border);
      border-radius: 10px;
      background: var(--panel);
    }

    .controls {
      padding: 14px;
      align-self: start;
    }

    .controls h2 {
      margin: 0 0 12px;
      font-size: 16px;
    }

    .form-row {
      margin-bottom: 10px;
    }

    .form-row label,
    .section-label {
      display: block;
      margin-bottom: 5px;
      font-size: 12px;
      font-weight: bold;
    }

    input,
    select,
    button {
      font: inherit;
    }

    input[type="text"],
    input[type="number"],
    select {
      width: 100%;
      padding: 8px 9px;
      border: 1px solid #aeb7c2;
      border-radius: 6px;
      background: white;
      font-size: 13px;
    }

    input:disabled,
    select:disabled {
      background: #eef1f5;
      color: #8a94a3;
    }

    .two-col {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 8px;
    }

    .three-col {
      display: grid;
      grid-template-columns: 1fr 1fr 1fr;
      gap: 8px;
    }

    .file-row {
      display: grid;
      grid-template-columns: 1fr auto;
      gap: 8px;
      align-items: center;
    }

    .file-name {
      min-height: 36px;
      padding: 9px;
      overflow: hidden;
      border: 1px solid #aeb7c2;
      border-radius: 6px;
      background: var(--soft);
      color: var(--muted);
      font-size: 12px;
      white-space: nowrap;
      text-overflow: ellipsis;
    }

    button {
      padding: 9px 13px;
      border: 1px solid #8c96a3;
      border-radius: 6px;
      background: white;
      cursor: pointer;
      font-size: 13px;
    }

    button:hover {
      background: #f2f4f7;
    }

    button.primary {
      border-color: var(--primary);
      background: var(--primary);
      color: white;
      font-weight: bold;
    }

    button.primary:hover {
      background: var(--primary-hover);
    }

    button.success {
      border-color: var(--success);
      background: var(--success);
      color: white;
      font-weight: bold;
    }

    button.success:hover {
      filter: brightness(0.94);
    }

    button:disabled {
      cursor: not-allowed;
      opacity: 0.55;
    }

    .button-stack {
      display: grid;
      gap: 8px;
      margin-top: 10px;
    }

    .button-pair {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 8px;
    }

    .check-row {
      display: flex;
      gap: 8px;
      align-items: center;
      min-height: 32px;
      font-size: 12px;
    }

    .lag-row {
      display: grid;
      grid-template-columns: minmax(0, 1fr) 145px;
      gap: 8px;
      align-items: center;
      margin-bottom: 8px;
    }

    .group {
      margin: 12px 0;
      padding: 10px;
      border: 1px solid var(--border);
      border-radius: 7px;
      background: #fbfcfd;
    }

    .group-title {
      margin-bottom: 9px;
      font-size: 12px;
      font-weight: bold;
    }

    .status {
      min-height: 22px;
      margin-top: 10px;
      color: var(--muted);
      font-size: 12px;
      line-height: 1.4;
    }

    .status.success {
      color: var(--success);
    }

    .status.error {
      color: var(--danger);
    }

    .status.warning {
      color: var(--warning);
    }

    .model-summary {
      max-height: 180px;
      margin-top: 10px;
      padding: 9px;
      overflow: auto;
      border: 1px solid var(--border);
      border-radius: 6px;
      background: #0f172a;
      color: #d1fae5;
      font: 11px/1.45 Consolas, monospace;
      white-space: pre-wrap;
    }

    .plots {
      min-width: 0;
      padding: 12px;
    }

    .plot-grid {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 12px;
    }

    .chart-panel {
      min-width: 0;
    }

    .chart-panel.wide {
      grid-column: span 2;
    }

    .chart-title {
      margin-bottom: 6px;
      font-size: 12px;
      font-weight: bold;
    }

    .chart-wrap {
      position: relative;
      min-height: 300px;
      border: 1px solid var(--border);
      border-radius: 7px;
      background: white;
      padding: 6px;
    }

    .metrics {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 8px;
      margin-top: 10px;
    }

    .metric {
      padding: 9px;
      border: 1px solid var(--border);
      border-radius: 7px;
      background: var(--soft);
    }

    .metric span {
      display: block;
      color: var(--muted);
      font-size: 11px;
    }

    .metric strong {
      display: block;
      margin-top: 4px;
      font-size: 16px;
    }

    .footer-note {
      margin-top: 10px;
      color: var(--muted);
      font-size: 11px;
      line-height: 1.45;
    }

    @media (max-width: 1120px) {
      .layout {
        grid-template-columns: 1fr;
      }

      .plot-grid {
        grid-template-columns: 1fr 1fr;
      }

      .chart-panel.wide {
        grid-column: span 2;
      }
    }

    @media (max-width: 720px) {
      body {
        padding: 8px;
      }

      .two-col,
      .three-col,
      .button-pair,
      .metrics,
      .plot-grid {
        grid-template-columns: 1fr;
      }

      .chart-panel.wide {
        grid-column: span 1;
      }

      .lag-row {
        grid-template-columns: 1fr;
      }
    }
    .copyright-footer {
  margin-top: 24px;
  padding: 14px 20px;
  border-top: 1px solid #d7dce4;
  background: #f8fafc;
  color: #667085;
  font-family: Arial, sans-serif;
  font-size: 12px;
  line-height: 1.6;
  text-align: center;
}

.backend-status {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: -2px 0 12px;
  padding: 8px 10px;
  border: 1px solid var(--border);
  border-radius: 7px;
  background: var(--soft);
  color: var(--muted);
  font-size: 12px;
}
.backend-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: #98a2b3;
}
.backend-status.online .backend-dot { background: var(--success); }
.backend-status.offline .backend-dot { background: var(--danger); }
.backend-status.checking .backend-dot { background: var(--warning); }
.warning-list {
  margin: 8px 0 0;
  padding-left: 18px;
  color: var(--warning);
  font-size: 11px;
  line-height: 1.45;
}