步骤

  1. 进入Typora主题文件根目录

  2. 新建文件base.user.css,复制下面内容

    /* Path: base.user.css */
    /* 侧边目录添加编号 二级标题开始*/
    .sidebar-content {
    counter-reset: h2
    }
    .outline-h2 {
    counter-reset: h3
    }
    .outline-h3 {
    counter-reset: h4
    }
    .outline-h4 {
    counter-reset: h5
    }
    .outline-h5 {
    counter-reset: h6
    }

    .outline-h2>.outline-item>.outline-label:before {
    counter-increment: h2;
    content: counter(h2) " "
    }
    .outline-h3>.outline-item>.outline-label:before {
    counter-increment: h3;
    content: counter(h2) "." counter(h3) " "
    }
    .outline-h4>.outline-item>.outline-label:before {
    counter-increment: h4;
    content: counter(h2) "." counter(h3) "." counter(h4) " "
    }
    .outline-h5>.outline-item>.outline-label:before {
    counter-increment: h5;
    content: counter(h2) "." counter(h3) "." counter(h4) "." counter(h5) " "
    }
    .outline-h6>.outline-item>.outline-label:before {
    counter-increment: h6;
    content: counter(h2) "." counter(h3) "." counter(h4) "." counter(h5) "." counter(h6) " "
    }


    /* 标题添加编号 */
    #write {
    counter-reset: h2
    }
    h2 {
    counter-reset: h3
    }
    h3 {
    counter-reset: h4
    }
    h4 {
    counter-reset: h5
    }
    h5 {
    counter-reset: h6
    }
    /** put counter result into headings */
    #write h2:before {
    counter-increment: h2;
    content: counter(h2)
    }
    #write h3:before,
    h3.md-focus.md-heading:before /** override the default style for focused headings */ {
    counter-increment: h3;
    content: counter(h2) "." counter(h3)
    }
    #write h4:before,
    h4.md-focus.md-heading:before {
    counter-increment: h4;
    content: counter(h2) "." counter(h3) "." counter(h4)
    }
    #write h5:before,
    h5.md-focus.md-heading:before {
    counter-increment: h5;
    content: counter(h2) "." counter(h3) "." counter(h4) "." counter(h5)
    }
    #write h6:before,
    h6.md-focus.md-heading:before {
    counter-increment: h6;
    content: counter(h2) "." counter(h3) "." counter(h4) "." counter(h5) "." counter(h6)
    }
    /** override the default style for focused headings */
    #write>h3.md-focus:before,
    #write>h4.md-focus:before,
    #write>h5.md-focus:before,
    #write>h6.md-focus:before,
    h3.md-focus:before,
    h4.md-focus:before,
    h5.md-focus:before,
    h6.md-focus:before {
    color: inherit;
    border: inherit;
    border-radius: inherit;
    position: inherit;
    left:initial;
    float: none;
    top:initial;
    font-size: inherit;
    padding-left: inherit;
    padding-right: inherit;
    vertical-align: inherit;
    font-weight: inherit;
    line-height: inherit;
    }
  3. 重启Typora

效果

image-20240102110921512