feat: added header

assets/scss/index.scss

@@ -0,0 +1,18 @@
+// Base
+
+@import './b-vars';
+@import './b-mixins';
+@import './b-reset';
+
+// Modules
+
+@import './m-container';
+@import './m-logo';
+@import './m-social-link';
+@import './m-button';
+
+// Layouts
+
+@import './l-header';
+@import './l-main';
+@import './l-footer';