Answer :
Just add this code to your text area and you are ready to customize from first moment -
<style> .sfc-action-button { color: #ffffff !important; font-size: 26px !important; height: 36px !important; background-color: #858585!important; background-image: none !important; } </style>In case, just in case, If HTML Sensitization is enabled by your admin - You are bit unlucky. Still you can do a few stuffs using JavaScript codes. A Small Example code here-
$(".sfc-action-button").css({ "width":"600 px", "font-size": "200%"});