@Test
void color() {

    LocalDateTime date = LocalDateTime.of(2020, 1, 1, 0, 0, 0);
    assertThat(service.color(Severity.WARN, date)).isEqualTo("#ff5c33");
    assertThat(service.color(Severity.WARN, date.plusWeeks(1))).isEqualTo("#ff9933");
    assertThat(service.color(Severity.ERROR, date)).isEqualTo("#a30101");
    assertThat(service.color(Severity.ERROR, date.plusWeeks(1))).isEqualTo("#e62a00");
}