slack-ui-revert.css

body {
  --sk_primary_background: 38,38,38 !important;
}
.c-wysiwyg_container--theme_dark,
.c-wysiwyg_container__formatting,
.then {
  background-color: #212121 !important;
}


.p-client_workspace--including_tab_rail {
  grid-template-areas: "p-client-workspace" !important;
  grid-template-columns: auto !important;
}

.p-tab_rail {
  display: none;
}

.p-client_workspace {
  padding: 0 !important;
}

.p-client_workspace__layout {
  border-radius: 0 !important;
  border-left: none !important;
  border-right: none !important;
}


.p-view_contents--sidebar {
  border-right-color: rgba(255, 255, 255, 0.2) !important;
}

[role="toolbar"],
.p-ia4_sidebar_header,
.p-channel_sidebar,
.then {
  background-color: #212121 !important;
}

.c-message_kit__background--hovered {
  background-color: rgba(255, 255, 255, 0.05);
}