hugo-theme-introduction/assets/vendor/fontawesome-free/scss/_bordered-pulled.scss

// bordered + pulled icons
// -------------------------

.#{$fa-css-prefix}-border {
  border-color: var(--#{$fa-css-prefix}-border-color, #{$fa-border-color});
  border-radius: var(--#{$fa-css-prefix}-border-radius, #{$fa-border-radius});
  border-style: var(--#{$fa-css-prefix}-border-style, #{$fa-border-style});
  border-width: var(--#{$fa-css-prefix}-border-width, #{$fa-border-width});
  padding: var(--#{$fa-css-prefix}-border-padding, #{$fa-border-padding});
}

.#{$fa-css-prefix}-pull-left { 
  float: left;
  margin-right: var(--#{$fa-css-prefix}-pull-margin, #{$fa-pull-margin}); 
}

.#{$fa-css-prefix}-pull-right { 
  float: right;
  margin-left: var(--#{$fa-css-prefix}-pull-margin, #{$fa-pull-margin}); 
}