It should be possible to add a border to thumbnails. You need to add a CSS rule for this. Please post a link to a page on your site that has thumbnails if you need help with adding an appropriate rule.
Also please explain more fully about what you mean by multi-tabs? Do you have an example you can link to?
not my theme but see the second sidebar on right has multitabs at the top.
http://demo.woothemes.com/?name=headlines
popular, latest, comments, tags
Also thumbnails in Special Recent Post sidebar is set to like 65×65, Im just wondering where can I find the code to add something like:
////special recent posts//////
.special-recent-posts-thumbnail img {
border: 1px solid #D3D3D3;
Im assuming it would be simple like that
There are a few tabbed widget plugins that the authors have made available on the ww.wp.xz.cn plugins directory http://ww.wp.xz.cn/plugins/search.php?q=tabbed+widgets
The CSS to style your thumbnail images will be in your theme’s stylesheet. To add the outline you would add the additional rule to the stylesheet of your child theme if you are using one, or a custom CSS plugin (including the custom CSS module of JetPack)