elections2021: Visual fixes

elections2021/templates/elections2021/_benefit_block.html

...ons2021/templates/elections2021/_floating_navigation.html

...ions2021/templates/elections2021/_main_benefit_block.html

elections2021/templates/elections2021/base.html

...2021/templates/elections2021/elections2021_home_page.html

...1/templates/elections2021/elections2021_program_page.html

...lates/elections2021/elections2021_program_point_page.html

...templates/elections2021/elections2021_strategic_page.html

elections2021/templatetags/elections2021_extras.py