Mainly CSS tweaks to fix padding and alignment of content

src/app/assets/stylesheets/_themes.scss

src/app/assets/stylesheets/_variables.scss

src/app/assets/stylesheets/foundation-overrides.scss

src/app/assets/stylesheets/markdown.scss

src/app/components/App.jsx

src/app/components/App.scss

src/app/components/cards/PostFull.scss

src/app/components/modules/SignUp.scss

src/app/components/pages/Faq.jsx

src/app/components/pages/PostsIndex.scss

src/app/components/pages/Privacy.jsx

src/app/components/pages/RecoverAccountStep1.jsx

src/app/components/pages/RecoverAccountStep1.scss

src/app/components/pages/TagsIndex.jsx

src/app/components/pages/Tos.jsx

src/app/components/pages/Welcome.jsx

src/app/help/en/welcome.md