i.mce-i-icon { font: 400 20px/1 dashicons; padding: 0; vertical-align: top; speak: none; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; margin-left: -2px; padding-right: 2px } i.gk-own-icon { background-image: url('custom-icon.png'); } /* Fix for the TinyMCE styling in WordPress */ .mce-toolbar .mce-container .mce-btn-group { display: inline-block; }