jQuery (edge), HTML, CSS, JavaScript
Mootools 1.3.2, HTML, CSS, JavaScript
Change class name on click in jQuery
No-Library (pure JS), HTML, CSS, JavaScript
http://stackoverflow.com/a/17495052/2170192
Basic parallax demo from http://code.tutsplus.com/tutorials/a-simple-parallax-scrolling-technique--net-27641. See also http://jonathannicol.com/projects/parallax-scrolling/
jQuery Slim 3.1.1, HTML, SCSS, JavaScript
jQuery 1.9.1, HTML, CSS, JavaScript
No-Library (pure JS), HTML, SCSS, JavaScript
jQuery 2.2.4, HTML, CSS, JavaScript
jQuery 3.3.1, HTML, CSS, JavaScript
No-Library (pure JS), HTML, PostCSS (Stage 0+), JavaScript