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                <button class="btn">
  Hello Custom Blue

<button class="btn red">
  Hello Custom Red

<button class="btn green">
  Hello Custom Green


                // private variables only available at build time of your theme
$internal-color-neutral-100: #fff;
$internal-color-neutral-500: #2d2d2d;
$internal-button-padding: 12px 24px;

// public custom properties in theme available for consumer
.btn {
  padding: var(--button-padding, $internal-button-padding);
  background-color: var(--button-background-color, $internal-color-neutral-500);
  color: var(--button-color, $internal-color-neutral-100);

// users can add their own styles and change properties in their own custom themes
:root {
  --button-background-color: blue;
} {
  --button-background-color: red;
} {
  --button-background-color: green;