The <code>transform</code> property has a variety of functions that let you scale, move, rotate, skew, etc., your elements. When used with pseudo-classes such as <code>:hover</code> that specify a certain state of an element, the <code>transform</code> property can easily add interactivity to your elements.
Add a CSS rule for the <code>hover</code> state of the <code>div</code> and use the <code>transform</code> property to scale the <code>div</code> element to 1.1 times its original size when a user hovers over it.
testString: assert(code.match(/div:hover\s*?{\s*?transform:\s*?scale\(1\.1\);/gi), 'The size of the <code>div</code> element should scale 1.1 times when the user hovers over it.');