gitea/frontend/default/public/css/theme-github.css

body {
  font-family: -apple-system,BlinkMacSystemFont,"Segoe UI",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol" !important;
  font-size: 14px;
  line-height: 1.5;
  color: #24292e;
}

a {
  color: #0366d6;
}

.following.bar.light {
  background-color: #24292e;
  color: rgba(255,255,255,0.75);
  border-bottom: none;
}

.ui.main.menu {
  font-size: 14px;
}

.ui.menu, .markdown:not(code), .ui.button, .ui.header {
  font-family: -apple-system,BlinkMacSystemFont,"Segoe UI",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol";	
}

.ui.main.menu .item {
  color: rgba(255,255,255,1);
  font-weight: 600;
}

.ui.secondary.main.menu .active.item {
  color: rgba(255,255,255,1);
  font-weight: 600;
}

.ui.secondary.main.menu .active.item:hover {
  color: rgba(255,255,255,0.75);
}

.ui.secondary.main.menu a.item:hover {
  color: rgba(255,255,255,0.75);
}

.ui.secondary.main.menu .dropdown.item:hover {
  color: rgba(255,255,255,0.75);
}

.repository.view.issue .title h1 {
  font-size: 32px;
  font-weight: 400;
  word-wrap: break-word;
}

.ui.green.button {
  background-color: #28a745;
  background-image: linear-gradient(-180deg, #34d058 0%, #28a745 90%);
}

.ui.green.button:hover {
  background-color: #269f42;
  background-image: linear-gradient(-180deg, #2fcb53 0%, #269f42 90%);
}

.ui.button {
  border: 1px solid rgba(27,31,35,0.2);
  border-radius: 0.25em;
  background-color: #eff3f6;
  background-image: linear-gradient(-180deg, #fafbfc 0%, #eff3f6 90%);
  font-size: 12px;
  font-weight: 600;
}

.ui.button:hover {
  border-color: rgba(27,31,35,0.5);
  background-color: #e6ebf1;
  background-image: linear-gradient(-180deg, #f0f3f6 0%, #e6ebf1 90%);
}

.ui.buttons .button:first-child {
  border-left: 1px solid rgba(27,31,35,0.2);
}

.ui.buttons .button:first-child:hover {
  border-left-color: rgba(27, 31, 35, 0.5);
}

.ui.blue.button, .ui.tiny.blue.buttons.button, .ui.tiny.blue.buttons a.ui.button {
  background-color: #2185d0;
  background-image: linear-gradient(-180deg, #3e98db 0%, #2185d0 90%);
}

.ui.blue.button:hover, .ui.tiny.blue.buttons.button:hover, .ui.tiny.blue.buttons a.ui.button:hover {
  background-color: #1c6fac;
  background-image: linear-gradient(-180deg, #2185d0 0%, #1c6fac 90%);
}

.ui.red.button {
  background-color: #ca1010;
  background-image: linear-gradient(-180deg, #e72525 0%, #ca1010 90%);
}

.ui.red.button:hover {
  background-color: #af0e0e;
  background-image: linear-gradient(-180deg, #ca1010 0%, #af0e0e 90%);
}

.ui.breadcrumb a {
  color: #0366d6;
}

.repository .header-grid .ui.huge.breadcrumb {
  font-size: 18px;
  font-weight: 600;
}

.ui.compact.labeled.button, .ui.compact.button a {
  color: #24292e;
  font-size: 12px;
  font-weight: 600;
}

.ui.table td.message a {
  color: #6a737d;
}

.ui.table td.name a:hover, .ui.table td.message a:hover {
  text-decoration: underline;
  color: #0366d6;
}

#repo-files-table.ui.fixed.single.line.table thead tr.commit-list {
  background-color: #f1f8ff;
  border: 1px solid #c8e1ff;
}

#repo-files-table.ui.fixed.single.line.table thead tr.commit-list th {
  background-color: #f1f8ff;
  border-bottom: 1px solid #c8e1ff;
  font-size: 12px;
}

.ui.top.attached.header {
  background-color: #f6f8fa;
  font-size: 14px;
}

.ui.top.attached.header strong {
  font-weight: 600;
}

.ui.tabular.stackable.menu.navbar a.item {
  color: #586069;
}

.ui.tabular.stackable.menu.navbar a.item:hover {
  color: #24292e;	
}

.ui.tabular.stackable.menu.navbar a.active.item {
  font-weight: 400;
  color: #24292e;
}

.repository.file.list #repo-files-table tr:hover {
  background-color: #f6f8fa;
}

.repository .header-grid .mega-octicon {
  font-size: 18px;
  width: 20px;
}

.ui.label {
  font-size: 12px;
  font-weight: 600;
}