View file style/themes/nineteen/css/icons.css

.icon {
    vertical-align: middle;
    display: inline-flex;
}

.icon::before {
	display: inline-block;
	background-image: url('../images/ds-icons.png');
	background-repeat: no-repeat;
	width: 22px;
	height: 24px;
	content: " "; 
	zoom: .6;
}

.icon-bold::before {
	background-position: -3px -2px;
}

.icon-italic::before {
	background-position: -34px -2px;
	width: 16px;
	height: 24px;
}

.icon-link::before {
	background-position: -57px -1px;
	width: 26px;
	height: 26px;
}

.icon-underline::before {
	background-position: -86px -2px;
	width: 24px;
	height: 24px;
}

.icon-smile::before {
	background-position: -114px -2px;
	width: 24px;
	height: 24px;
}

.icon-strike::before {
	background-position: -140px -2px;
	width: 28px;
	height: 24px;
}

.icon-text-color::before {
	background-position: -170px -2px;
	width: 24px;
	height: 24px;
}

.icon-color::before {
	background-position: -197px -2px;
	width: 24px;
	height: 24px;
}

.icon-quote::before {
	background-position: -3px -33px;
	width: 21px;
	height: 18px;
}

.icon-more::before {
	background-position: -31px -39px;
	width: 22px;
	height: 6px;
}

.icon-more-vertical::before {
	background-position: -67px -31px;
	width: 6px;
	height: 22px;
}

.icon-code::before {
    background-position: -84px -30px;
    width: 28px;
    height: 24px;
}

.icon-mic::before {
	background-position: -117px -29px;
	width: 16px;
	height: 24px;
}

.icon-full::before {
	background-position: -142px -29px;
	width: 24px;
	height: 24px;
}

.icon-refull::before {
	background-position: -170px -29px;
	width: 24px;
	height: 24px;
}

.icon-close::before {
	background-position: -199px -32px;
	width: 20px;
	height: 20px;
}

.icon-update::before {
	background-position: -2px -57px;
	width: 24px;
	height: 24px;
}

.icon-image::before {
	background-position: -29px -60px;
	width: 25px;
	height: 20px;
}

.icon-upload::before {
	background-position: -57px -57px;
	width: 26px;
	height: 25px;
}

.icon-settings::before {
	background-position: -86px -58px;
	width: 24px;
	height: 24px;
}