w3-button-hover-red, w3-button-hover-green, w3-button-hover-blue, w3-button-hover-yellow, w3-button-hover-white, w3-button-hover-black, w3-button-hover-gray, w3-button-hover-grey, w3-button-hover-amber, w3-button-hover-aqua, w3-button-hover-light-blue, w3-button-hover-brown, w3-button-hover-cyan, w3-button-hover-blue-grey, w3-button-hover-blue-gray, w3-button-hover-light-green, w3-button-hover-indigo, w3-button-hover-khaki, w3-button-hover-lime, w3-button-hover-orange, w3-button-hover-deep-orange, w3-button-hover-pink, w3-button-hover-purple, w3-button-hover-deep-purple, w3-button-hover-sand, w3-button-hover-teal, w3-button-hover-light-gray, w3-button-hover-light-grey, w3-button-hover-dark-gray, w3-button-hover-dark-grey, w3-button-hover-pale-red, w3-button-hover-pale-yellow, w3-button-hover-pale-green and w3-button-hover-pale-blue