Principles
Text Color
                                    mixin
                                    class
                                    attribute
                                
                                    =.color
                                    =class="text color"
                                    =color="color"
                                
Background Color
                                    mixin
                                    class
                                    attribute
                                
                                    =.bg-color
                                    =class="bg color"
                                    =bg="color"
                                
Border color
                                    mixin
                                    class
                                    attribute
                                
                                    =.b-color
                                    =class="b-color"
                                    =border="color"