Rename folder scss with an "_" for Jekyll to ignore it

assets/_scss/_mixins.scss

@@ -0,0 +1,49 @@
+/* ==========================================================================
+   MIXINS
+   ========================================================================== */
+
+%tab-focus {
+  // Default
+  outline: thin dotted $warning-color;
+  // Webkit
+  outline: 5px auto $warning-color;
+  outline-offset: -2px;
+}
+
+/*
+   em function
+   ========================================================================== */
+
+@function em($target, $context: $doc-font-size) {
+  @return ($target / $context) * 1em;
+}
+
+
+/*
+   Bourbon clearfix
+   ========================================================================== */
+
+// Provides an easy way to include a clearfix for containing floats.
+//
+// @link http://cssmojo.com/latest_new_clearfix_so_far/
+//
+// @example scss - Usage
+//   .element {
+//     @include clearfix;
+//   }
+//
+// @example css - CSS Output
+//   .element::after {
+//     clear: both;
+//     content: "";
+//     display: table;
+//   }
+
+@mixin clearfix {
+  clear: both;
+  &::after {
+    clear: both;
+    content: "";
+    display: table;
+  }
+}