#cnblogs_post_body h2 {
    font-size: 21px;
    font-weight: bold;
    line-height: 1.5;
    margin: 10px 0;
    background: #b5ccff;
    border-radius: 6px;
}

/**  h2标签首部内容  **/ 
h2::before {
    content: "