use css variable for grid system and reorder utils

assets/sass/_theme/_configuration.sass

assets/sass/_theme/_utils.sass

assets/sass/_theme/_variables.sass

assets/sass/_theme/blocks/call_to_action.sass

assets/sass/_theme/blocks/chapter.sass

assets/sass/_theme/blocks/contact.sass

assets/sass/_theme/blocks/definitions.sass

assets/sass/_theme/blocks/features.sass

assets/sass/_theme/blocks/files.sass

assets/sass/_theme/blocks/gallery.sass

assets/sass/_theme/blocks/image.sass

assets/sass/_theme/blocks/organizations.sass

assets/sass/_theme/blocks/pages.sass

assets/sass/_theme/blocks/posts.sass

assets/sass/_theme/blocks/testimonials.sass

assets/sass/_theme/blocks/timeline.sass

assets/sass/_theme/blocks/video.sass

assets/sass/_theme/design-system/a11y.sass

assets/sass/_theme/design-system/footer.sass

assets/sass/_theme/design-system/hero.sass