jQuery 1.5.2, HTML, CSS, JavaScript
No-Library (pure JS), HTML, CSS, JavaScript
jQuery 3.4.1, HTML, CSS, JavaScript
jQuery 2.1.3, HTML, CSS, JavaScript
jQuery 3.2.1, HTML, CSS, JavaScript
http://stackoverflow.com/questions/11596626/how-can-i-change-a-divs-background-by-hovering-over-another-div/11596648#11596648
jQuery (edge), HTML, CSS, JavaScript