It works by embedding a <style> attribute with CSS animations within the SVG.<p>The same animation exists on the main site however it’s embedded in the page for wider browser support.<p>For the GitHub readme I combined the two SVG images and made some adjustments to use [transform-origin] instead of [margin].<p>It works with most modern browsers but not with IE, while the main site has broader browser support because everything is embedded on the page rather than in the SVG. Additionally the animation works better on a desktop than on my phone (iPhone with latest iOS).