fix grid breakpoint

assets/sass/_theme/blocks/definitions.sass

assets/sass/_theme/blocks/files.sass

assets/sass/_theme/blocks/gallery.sass

assets/sass/_theme/blocks/key_figures.sass

assets/sass/_theme/blocks/organization_chart.sass

assets/sass/_theme/blocks/pages.sass

assets/sass/_theme/blocks/posts.sass

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

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

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

assets/sass/_theme/sections/authors.sass

assets/sass/_theme/sections/diplomas.sass

assets/sass/_theme/sections/pages.sass

assets/sass/_theme/sections/posts.sass

assets/sass/_theme/sections/programs.sass