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                - var btns = ['primary','secondary','success','danger','warning','info','light','dark','link','lg','sm','brand-primary','brand-secondary','brand-tertiary'];
      h1.display-4 Auto Custom Bootstrap 4 Buttons
      each val in btns
        button(class='btn btn-' + val)= val


                //Colors - Any Colors You Want
$colors: (
  primary: #00a9e7,
  secondary: #09e3fe,
  success: #37ff3b,
  danger: #ee3426,
  warning: #e4de33,
  info: #00a9e7,
  light: #eee,
  dark: #444,
  brand-primary: #420dab, 
  brand-secondary: #36418c, 
  brand-tertiary: #c0d6e4

//Dark or Light background to determine text color
@function text-color($color) {
  @if (lightness($color) > 50) {
    @return #000; // Lighter backgorund, return dark color
  } @else {
    @return #fff; // Darker background, return light color

//Bootstrap Button - Make Any Customizations Here
@mixin custom-bootstrap-btns {
  //Generates the class names via the $colors Map
  @each $className in $colors {
    .btn-#{nth($className, 1)} {
      $buttonColor: nth($className, 2);
      background: $buttonColor;
      color: text-color($buttonColor);
      border-color: darken($buttonColor, 5%);
      &:hover {
        background: lighten($buttonColor, 10%);
        color: text-color(lighten($buttonColor, 10%));
        border-color: $buttonColor;
  //Button Sizes
  .btn {
    &-lg {
      //Any Size Customizations here
    &-sm {
      //Any Size Customizations here
    &-link {
      //Any Customizations here

//Boostrap Custom Buttons Mixin Call
@include custom-bootstrap-btns;

//Layout for Pen
body {
  background: #222;
button {
  margin: 10px;
  cursor: pointer;


                //Auto Custom Bootstrap 4 Buttons

//Created a Mixn so it can be stored in a partial, but doesn't have to be.

//The Mixin generates all the classes you need via the @each function

//Gives you complete control on how you want your custom buttons to look like, while using all the lovely bootstrap class names for buttons. Go ahead and play with the CSS to create your own custom buttons

//I had fun making this