created grid system

src/sass/abstracts/_mixins.scss

@@ -0,0 +1,7 @@
+@mixin clearfix {
+  &::after {
+    content: "";
+    display: table;
+    clear: both;
+  }
+}

src/sass/abstracts/_variables.scss

@@ -1,3 +1,4 @@
+// COLORS
 $color-primary: #55c57a;
 $color-primary-light: #55c57a;
 $color-primary-dark: #28b485;
@@ -5,3 +6,8 @@ $color-primary-dark: #28b485;
 $color-grey-dark: #777;
 $color-white: #fff;
 $color-black: #000;
+
+// GRID background
+$grid-width: 114rem;
+$gutter-vertical: 8rem;
+$gutter-horizontal: 6rem;