v0.5.0

• New --image-compare-handle-hover-color custom property: the grip
  arrows change color on hover and keyboard focus (:focus-visible).
  Defaults to the OS accent color where the browser supports the
  AccentColor keyword; elsewhere the arrows keep their regular color
  until the property is set (guarded via @supports — the keyword must
  not sit inside var(), or unsupporting browsers would blank the
  arrows).