Board Thread:Support Requests - Getting Technical/@comment-43852372-20191004230139/@comment-23989026-20191005113209

Help page → Help:Infoboxes/CSS There are 2 types of infobox theme - standard and europa - which dictates correct coding in MediaWiki:Wikia.css. As your wiki theme is using europa, each MediaWiki:Wikia.css item starts with .pi-europa
 * Introduction

To link MediaWiki:Wikia.css to the infobox, the infobox needs a theme. As your infobox is named NPC I have used theme="npc" which is added to the first line of the infobox

".pi-europa.pi-theme-npc" is a single word with no gaps .pi-europa.pi-theme-npc { border: 2px solid #ccc; }
 * add a thick border to the entire infobox

.pi-europa.pi-theme-npc .pi-data { border: 1px solid #ccc; }
 * add a thin borders around each row

this is the data rows .pi-europa.pi-theme-npc .pi-data { background-color: #eee; }
 * change the background colors of the infobox

comma after title .pi-europa.pi-theme-npc .pi-title, .pi-europa.pi-theme-npc .pi-header { background-color: #006cb0; }
 * change the background colors of headers

use Drops
 * the header to automatically disappear with no info

Example of above → w:c:communitytest:Template:NPC