Definition of rummage sale. : a usually informal sale of miscellaneous goods; especially : a sale of donated articles conducted by a nonprofit organization (such as a church or charity) to help support its programs.
About Hover.css. All Hover.css effects make use of a single element (with the help of some pseudo-elements where necessary), are self contained so you can easily copy and paste them, and come in CSS, Sass, and LESS flavours. Many effects use CSS3 features such as transitions, transforms and animations.
That property can then be used in CSS to apply a specific style to the element. It can also be used in JavaScript to find the element and apply some functionality to it. But it's perfectly possible that an element has a class property that occurs nowhere in JavaScript or CSS. In the developer tools, you can see what styles are applied to an element. With each piece of styling you can also see the CSS file where it came from, including the styles that are overridden by other styles. That doesn't give you all the reference to the class, though! If the CSS has a style that says div.twitter, it won't be applied to this element. Just as well, a.twitter:hover will only be applied when the element is hovered. So browsing the dev tools will not give you all references to a certain class. The best (only) way would be to just view the source of all CSS files and search in them.