I want to change WordPress's main gallery shortcode style to something like the picture below!
Any idea ?
WordPress Development Stack Exchange is a question and answer site for WordPress developers and administrators. It only takes a minute to sign up.Sign up to join this community
You can do that using the default gallery features already included in WordPress or install the Jetpack plugin which enables you to create tiled galleries. http://jetpack.me/support/tiled-galleries/
WordPress also includes a built in slide show feature and you can add thumbnail images underneath a full width image like what you linked to.