style(#16): edit buttons avoiding EBI-like style; correct behaviour when hover on sections links on second navbar

fix: prevent reappearance of the cookies banner when accepting cookies in any subpage different from home page

refactor(#4): replaced and cleanup styles.css by several _modules.scss in assets/sass/; refactor(images): relocate image resources (png, svg) into new directory images/, rename images following the easy-to-write kebab-case-convetion; refactor(proposal): change style of cards in resources section

refactor: change user consent acceptance from localStorage to document.cookie; feat(ui): change appearance of all call-to-action buttons (for example, 'Download table as CSV')

feat(styles): add sass capability with hugo builtin compiler called at layouts/partials/head.html (sass files should live inside assets/ directory at the root of the project, then they are compiled to regular css at resources/)