Update html.

Author: fniu

books/specifying-systems-cn/index.html

@@ -824,10 +824,8 @@ <h1 id="_准备开始" class="sect0">准备开始</h1>
 <div class="sect1">
 <h2 id="_些许简单数学">1. 些许简单数学</h2>
 <div class="sectionbody">
-<hr>
 <div class="paragraph text-center">
-<p><a href="#_前言"><span class="icon"><i class="fa fa-arrow-circle-left"></i></span></a> |
-<a href="#_简单时钟系统"><span class="icon"><i class="fa fa-arrow-circle-right"></i></span></a></p>
+<p><a href="#_前言"><span class="icon"><i class="fa fa-arrow-circle-left"></i></span></a>  <a href="#_简单时钟系统"><span class="icon"><i class="fa fa-arrow-circle-right"></i></span></a></p>
 </div>
 <hr>
 <div class="sect2">
@@ -895,14 +893,12 @@ <h3 id="_命题逻辑">1.1. 命题逻辑</h3>
 <col style="width: 33.3333%;">
 <col style="width: 33.3334%;">
 </colgroup>
-<thead>
+<tbody>
 <tr>
-<th class="tableblock halign-left valign-top"><em>F</em></th>
-<th class="tableblock halign-left valign-top"><em>G</em></th>
-<th class="tableblock halign-left valign-top"><em>F</em> &#8658; <em>G</em></th>
+<td class="tableblock halign-left valign-top"><p class="tableblock">\(F\)</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">\(G\)</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">\(F \implies G\)</p></td>
 </tr>
-</thead>
-<tbody>
 <tr>
 <td class="tableblock halign-left valign-top"><p class="tableblock">真</p></td>
 <td class="tableblock halign-left valign-top"><p class="tableblock">真</p></td>
@@ -948,24 +944,22 @@ <h3 id="_命题逻辑">1.1. 命题逻辑</h3>
 </div>
 <table class="tableblock frame-all grid-all" style="width: 90%;">
 <colgroup>
-<col style="width: 7.6923%;">
-<col style="width: 7.6923%;">
-<col style="width: 15.3846%;">
-<col style="width: 15.3846%;">
-<col style="width: 23.0769%;">
-<col style="width: 30.7693%;">
+<col style="width: 8.3333%;">
+<col style="width: 8.3333%;">
+<col style="width: 16.6666%;">
+<col style="width: 16.6666%;">
+<col style="width: 16.6666%;">
+<col style="width: 33.3336%;">
 </colgroup>
-<thead>
+<tbody>
 <tr>
-<th class="tableblock halign-left valign-top"><em>F</em></th>
-<th class="tableblock halign-left valign-top"><em>G</em></th>
-<th class="tableblock halign-left valign-top"><em>F</em> &#8658; <em>G</em></th>
-<th class="tableblock halign-left valign-top">&not; <em>F</em></th>
-<th class="tableblock halign-left valign-top">&not; <em>F</em> \/ <em>G</em></th>
-<th class="tableblock halign-left valign-top">(<em>F</em> &#8658; <em>G</em>) &equiv; &not; <em>F</em> \/ <em>G</em></th>
+<td class="tableblock halign-left valign-top"><p class="tableblock">\(F\)</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">\(G\)</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">\(F \implies G\)</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">\(\neg F\)</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">\(\neg F \vee G\)</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">\((F \implies G) \equiv \neg F \vee G\)</p></td>
 </tr>
-</thead>
-<tbody>
 <tr>
 <td class="tableblock halign-left valign-top"><p class="tableblock">真</p></td>
 <td class="tableblock halign-left valign-top"><p class="tableblock">真</p></td>