Most pages are now styled.

Small changes to existing pages.
Changes to base layout style.

resources/assets/sass/base/_container.scss

@@ -1,9 +1,26 @@
+@use "../abstracts/mixin" as *;
+
+body {
+  margin: 0;
+  padding: 0;
+}
 .site_container  {
-  max-width: 1440px;
-  margin: 0 auto;
+
 }
 .body_container {
-  padding: 67px 135px;
+  @include container;
+  padding: 67px 0;
   background-color: #f9f9f9;
-  margin: 0;
-}
+}
+.header_container  {
+  @include container;
+}
+.grey_background {
+  background-color: #f9f9f9;
+}
+.content_container {
+  padding-right: 50px;
+}
+.sidebar {
+  width: CALC(300px + var(--bs-gutter-x));
+}