    <style>
      html, body {
        height: 100%;
        margin: 0;
        padding: 0;
      }
  
      body {
        font-family: Arial, Helvetica, sans-serif;
        overflow: hidden;
        background: #ffffff;
        color: #000000;
      }
  
      .page-shell {
        display: flex;
        flex-direction: column;
        height: 100vh;
        overflow: hidden;
      }
  
      .top-area {
        flex: 0 0 auto;
        background: #ffffff;
        border-bottom: 1px solid #ccc;
        z-index: 1000;
      }
  
      .header-block {
        flex: 0 0 auto;
      }
  
      .meta-block {
        flex: 0 0 auto;
        padding: 8px 8px;
        font-size: 0.95em;
        color: #444;
        border-top: 1px solid #ddd;
        border-bottom: 1px solid #ddd;
        background: #f8f8f8;
      }
  
      .content-area {
        flex: 1 1 auto;
        min-height: 0;
        overflow-y: auto;
        background: #ffffff;
        padding: 16px;
        box-sizing: border-box;
      }
  
      .report-frame {
        width: 100%;
        height: 100%;
        border: none;
        display: block;
        background: #ffffff;
      }
  
      .footer-block {
        flex: 0 0 auto;
        background: #ffffff;
        border-top: 1px solid #ccc;
        z-index: 1000;
      }
    </style>