w3-gray
w3-grayscale
w3-image-gray
w3-filter-gray
w3-round
w3-circle
w3-image-round
w3-rounded
w3-italic
w3-font-italic
w3-style-italic
w3-i
w3-center
w3-middle
w3-align-center
w3-text-center
w3-border-all
w3-bordered
w3-border
w3-frame
w3-left-border
w3-leftbar
w3-bar-left
w3-panel-left