:root {
    --fg: #1a1a1a;
    --muted: #666;
    --border: #d4d4d4;
    --accent: #2563eb;
    --error: #c0392b;
    --success: #1e7e34;
  }
  
  * { box-sizing: border-box; }
  
  body {
    font-family: system-ui, -apple-system, "Hiragino Sans", "Noto Sans JP", sans-serif;
    color: var(--fg);
    line-height: 1.7;
    margin: 0;
  }
  
  .container {
    max-width: 680px;
    margin: 0 auto;
    padding: 40px 20px 80px;
  }
  
  header {
    border-bottom: 1px solid var(--border);
    margin-bottom: 32px;
    padding-bottom: 16px;
  }
  
  header nav a {
    margin-right: 16px;
    color: var(--accent);
    text-decoration: none;
  }
  
  h1 { font-size: 1.6rem; }
  
  .field { margin-bottom: 20px; }
  
  .field label {
    display: block;
    font-weight: 600;
    margin-bottom: 6px;
  }
  
  .field .required {
    color: var(--error);
    font-size: 0.85em;
    margin-left: 4px;
  }
  
  .field input,
  .field textarea {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 1rem;
    font-family: inherit;
  }
  
  .field input:focus,
  .field textarea:focus {
    outline: 2px solid var(--accent);
    outline-offset: 1px;
  }
  
  .hint {
    font-size: 0.85rem;
    color: var(--muted);
    margin-top: 4px;
  }
  
  /* ハニーポット：人間には見せない */
  .hp {
    position: absolute;
    left: -9999px;
    width: 1px;
    height: 1px;
    overflow: hidden;
  }
  
  button {
    background: var(--accent);
    color: #fff;
    border: none;
    border-radius: 6px;
    padding: 12px 32px;
    font-size: 1rem;
    cursor: pointer;
  }
  
  button:disabled {
    background: #9ca3af;
    cursor: not-allowed;
  }
  
  #status {
    margin-top: 20px;
    padding: 12px 16px;
    border-radius: 6px;
    display: none;
  }
  
  #status.show { display: block; }
  #status.error { background: #fdecea; color: var(--error); }
  #status.success { background: #e6f4ea; color: var(--success); }
  #status.loading { background: #f1f3f5; color: var(--muted); }