chromium/third_party/blink/web_tests/inspector-protocol/css/resources/coverage2.css

.notEverUsed {
  color: pink;
}

.usedSomewhatLater { background-color: mediumspringgreen; }

.usedStraightAway {
  background-color: rebeccapurple;
}

.usedAtTheVeryEnd {
  background-color: palegoldenrod;
}