blockscout/apps/block_scout_web/assets/css/components/_dot.scss

.transaction {

  &__dot {
    display: inline-block;
    height: 10px;
    width: 10px ;
    border-radius: 50%;
    margin-left: 5px;
    vertical-align: baseline;

    &--pending { background-color: $gray-500; }
    &--success { background-color: $success; }
    &--failed { background-color: $danger; }
    &--out_of_gas { background-color: $warning; }
  }
}