Today I’ll give you a small tip for the WordPress Gallery. With version 3.1 of WordPress it is possible to replace the inline style of the core, it’s done easily with a Filter-Hook. Use this and include your custom style with the Theme in your frontend; no Plugins, CSS or functions in your Theme for this required – easy, but it works and this is the greatest part of WordPress – Hooks for everyone, everywhere
add_filter( 'use_default_gallery_style', '__return_false' );
If you don`t understand the function
__return_false() of the WP Core, please read our post for this function.