help customizing search bar and search results page

i would love some assistance with this page on my website, i've been trying to figure it out for hours. 

i added a search bar to my blog page, and it operates fine but i can't customize the design. i finally figured out how to change the design of the search bar itself with css, all except for changing "Search" to all lowercase "search", so i'd love help with that if possible. 

i'd also love some help fixing a few things on the results page:

- rounding the search bar and changing the text and background color

- changing the color of the search result blogs text so it contracts more on the green background

- change the results from italicized word to bold word

and if possible, i'd also love some assistance withe css to round the newsletter sign up boxes so they match my rounded search bars. i know it's a lot so thank you to anyone who can help!

If you share link to a search result page, we can help easier