elections2021: Candidates updates and refactorings

elections2021/constants.py

elections2021/models.py

elections2021/static/elections2021/css/styles.css

...ns2021/static/elections2021/images/archetype/vzdelani.svg

...2021/static/elections2021/images/archetype/vzdelavani.svg

elections2021/templates/elections2021/_candidate_card.html

...ons2021/templates/elections2021/_candidate_list_item.html

elections2021/templates/elections2021/_page_header.html

...templates/elections2021/elections2021_candidate_page.html

...tes/elections2021/elections2021_candidates_list_page.html