body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.6;
    background-color: #f4f7f9;
    color: #333;
    margin: 0;
    padding: 20px;
  }
  .container {
    max-width: 800px;
    margin: 0 auto;
    background: #fff;
    padding: 20px 30px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
  }
  h1, h2 {
    color: #111;
    border-bottom: 1px solid #eee;
    padding-bottom: 10px;
    margin-top: 0;
  }
  h2 {
    margin-top: 30px;
  }
  textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 4px;
    font-family: "SF Mono", "Fira Code", "Fira Mono", "Roboto Mono", monospace;
    font-size: 14px;
    box-sizing: border-box;
    resize: vertical;
  }
  textarea[readonly] {
    background-color: #f0f0f0;
    cursor: copy;
  }
  button {
    display: block;
    width: 100%;
    padding: 12px;
    margin-top: 15px;
    font-size: 16px;
    font-weight: bold;
    color: #fff;
    background-color: #007bff;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.2s;
  }
  button:hover {
    background-color: #0056b3;
  }
  .hidden {
    display: none;
  }
  .output-group {
    margin-top: 20px;
  }
  .output-group label {
    display: block;
    font-weight: bold;
    margin-bottom: 8px;
  }
  #outputImageContainer {
    padding: 15px;
    border: 1px dashed #ccc;
    border-radius: 4px;
    margin-bottom: 10px;
    overflow: auto;
    background-color: #f9f9f9;
  }