做兼职的时候，给一个论坛界面修改完善的时候，IE正常，在Firefox下总是有不明border出现，我把，html 的style 仔细检查，也没有什么结果，仍然出现，折腾了好几个小时。最后索性把样式全部去掉，不信你还能出现。结果还是出现了。无聊之余，我看到一个没有见过的table属性：
<table rules = "all" >
删除之，发现终于border不见了，看来我对html markup好多都不知道，赶紧搜索这个恶心的玩意。

结果如下： Quote RULES Attribute | rules Property

Sets or retrieves which dividing lines (inner borders) are displayed.

Syntax

HTML: <TABLE RULES = sRule... >
Scripting: [ sRule = ] TABLE.rules

Possible Values

sRule / String that specifies or receives one of the following values.
all  / Borders are displayed on all rows and columns.
cols /  Borders are displayed between all table columns.
groups /  Horizontal borders are displayed between all tHead, tBody, and tFoot objects; vertical borders are displayed between all colGroup objects.
none /  All interior table borders are removed.
rows /  Horizontal borders are displayed between all table rows.W3C的内容 Quote rules = none|groups|rows|cols|all
This attribute specifies which rules will appear between cells within a table. The rendering of rules is user agent dependent. Possible values:

* none: No rules. This is the default value.
* groups: Rules will appear between row groups (see THEAD, TFOOT, and TBODY) and column groups (see COLGROUP and COL) only.
* rows: Rules will appear between rows only.
* cols: Rules will appear between columns only.
* all: Rules will appear between all rows and columns.