Bloc de titre - collapsed (#666)

assets/js/theme/design-system/collapse.js

assets/js/theme/index.js

assets/sass/_theme/blocks/base.sass

assets/sass/_theme/blocks/title.sass

assets/sass/_theme/configuration/blocks.sass

assets/sass/_theme/configuration/icons.sass

assets/sass/_theme/hugo-osuny.sass

layouts/partials/blocks/list.html

layouts/partials/blocks/templates/title.html

layouts/partials/blocks/toc.html

layouts/partials/contents/list.html