.sub-list { list-style: none; padding: 0; margin: 8px 0 0 1em; }
    .sub-list li { font-size: 14px; line-height: 1.9; color: #555; padding-left: 1.2em; position: relative; }
    .sub-list li::before { content: "・"; position: absolute; left: 0; color: #1a3a5c; }
    .diagram { text-align: center; }
    .diagram img { max-width: 420px; width: 100%; height: auto; border: 1px solid #c8d8e8; border-radius: 2px; }