自用Typora样式（自动编号功能）

示例：

代码：

/** initialize css counter
  * 从h2开始编号 
  */
#write {
    counter-reset: h2
}

h1 {
    text-align:center
}

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 {
    counter-increment: h3;
    content: counter(h2) "." counter(h3) ". "
}

#write h4:before,
h4.md-focus.md-heading:before /** override the default style for focused headings */ {
    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;
}

.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) ". "
}

/**************************************
 * Header Counters in TOC
 **************************************/
 
/* No link underlines in TOC */
.md-toc-inner {
    text-decoration: none;
}
 
.md-toc-content {
    counter-reset: h2toc
}
 
.md-toc-h2 {
    font-size: 1.1rem;
    margin-left: 2rem;
    counter-reset: h3toc
}
 
.md-toc-h3 {
    margin-left: 3rem;
    font-size: .9rem;
    counter-reset: h4toc
}
 
.md-toc-h4 {
    margin-left: 4rem;
    font-size: .85rem;
    counter-reset: h5toc
}
 
.md-toc-h5 {
    margin-left: 5rem;
    font-size: .8rem;
    counter-reset: h6toc
}
 
.md-toc-h6 {
    margin-left: 6rem;
    font-size: .75rem;
}
 
.md-toc-h2 .md-toc-inner {
    margin-left: 0;
}

.md-toc-h2:before {
    color: black;
    counter-increment: h2toc;
    content: counter(h2toc) ". "
}
 
.md-toc-h2 .md-toc-inner {
    margin-left: 0;
}
 
.md-toc-h3:before {
    color: black;
    counter-increment: h3toc;
    content: counter(h2toc) ". " counter(h3toc) ". "
}
 
.md-toc-h3 .md-toc-inner {
    margin-left: 0;
}
 
.md-toc-h4:before {
    color: black;
    counter-increment: h4toc;
    content: counter(h1toc) ". " counter(h2toc) ". " counter(h3toc) ". " counter(h4toc) ". "
}
 
.md-toc-h4 .md-toc-inner {
    margin-left: 0;
}
 
.md-toc-h5:before {
    color: black;
    counter-increment: h5toc;
    content: counter(h1toc) ". " counter(h2toc) ". " counter(h3toc) ". " counter(h4toc) ". " counter(h5toc) ". "
}
 
.md-toc-h5 .md-toc-inner {
    margin-left: 0;
}
 
.md-toc-h6:before {
    color: black;
    counter-increment: h6toc;
    content: counter(h1toc) ". " counter(h2toc) ". " counter(h3toc) ". " counter(h4toc) ". " counter(h5toc) ". " counter(h6toc) ". "
}
 
.md-toc-h6 .md-toc-inner {
    margin-left: 0;
}

参考文献：

http://support.typora.io/Auto-Numbering/
https://pastebin.com/XmYgBbaz
https://pastebin.com/NYugSbXk