Additional site tweaks

[joshdarby]

Changes

This pull request makes the following changes:

• Removes the newsletter singnup form from archives and the old series template https://github.com/INN/umbrella-citylimits/commit/f48a3f898d6ce704431343ad7598715df2fcc41f
• Reduces placeholder text size and updates width settings for the sidebar newsletter signup https://github.com/INN/umbrella-citylimits/commit/963bddb92b54f5993526660a19b5804883d5a007
• Updates header buttons to not get squished on smaller screen sizes https://github.com/INN/umbrella-citylimits/commit/a88f8466e8ecb1d3d1a5633c51b4aa65aabd5a49
• Removes gray overlay from homepage special projects images and moves the title to below the image https://github.com/INN/umbrella-citylimits/commit/1689f753b5fb6f30300733be776b5461172ca2bc

Why

For #141

Testing/Questions

Features that this PR affects:

• Header buttons
• Newsletter signup form being hardcoded on templates
• Newsletter signup form in the sidebar
• Homepage special projects widget

Questions that need to be answered before merging:

• [x] Is this PR targeting the correct branch in this repository?
• [x] Is the new spacing ok between the image / title / first post in the screenshot below?
• [x] There's not a great way to make sure all of the title heights are the same now that they are moved below the image, resulting in the lists of series posts looking uneven if a title has 2 lines vs 1. Any thoughts @benlk or @MirandaEcho?

Steps to test this PR:

Newsletter on archives and old series template:

1. Go to an archive page, such as an author page, and verify the hardcoded version of the newsletter isn't present
2. Do #1 again but on a series landing page using the old template

Sidebar newsletter signup placeholders

1. View the sidebar newsletter widget on a narrow-ish screen size and verify you can still read the input placeholders

Header buttons being squished

1. View the header on a narrow screen size and verify the buttons don't crash into each other anymore

Homepage special projects title/image

1. View the homepage special projects widget and verify no image overlay is present
2. Make sure the title and image link still work as expected

[benlk]

There's not a great way to make sure all of the title heights are the same now that they are moved below the image, resulting in the lists of series posts looking uneven if a title has 2 lines vs 1.

CSS Grid might work here, but it would require a lot of micromanaging of position of elements and probably more than a bit of display: contents;.

[joshdarby]

CSS Grid might work here, but it would require a lot of micromanaging of position of elements and probably more than a bit of display: contents;

That's what I figured. 😕