Template:Resource/styles.css

th.wiki-dynamic-header {
  background-color: #eaecee;
  color: #202122;
  text-align:center;
  font-weight: bold;
  font-size: 75%;
  padding:0.1em;
}
html.skin-theme-clientpref-night th.wiki-dynamic-header {
  background-color: #2d2d30 !important;
  color: #ffffff !important;
  text-align:center;
  font-weight: bold;
  font-size: 75%;
  padding:0.1em;
}