Template:Resource/styles.css

.wiki-custom-table {
  min-width: 225px !important;
  border: 2px solid #f8f9fa !important;
}
.wiki-dynamic-header {
  text-align: center;
  font-weight: bold;
  font-size: 75%;
  padding: 0.1em;
  background-color: #eaecee !important; /* light gray background */
  color: #202122 !important;            /* Dark text */
}
html.skin-theme-clientpref-night .wiki-custom-table .wiki-dynamic-header {
  background-color: #2d2d30 !important; /* Dark gray background */
  color: #ffffff !important;            /* White text */
}