Vulcan/packages/example-customization/lib/stylesheets/custom.scss

.logo-hello {
  display: flex;
  justify-content: center;
  color: #333;
}

.post-red{
  background-color: #FFD3D2;
}
.post-blue{
  background-color: #D2F5FF;
}
.post-yellow{
  background-color: #FBFFD2;
}
.post-green{
  background-color: #D2FFD2;
}