Clean ajaxify styles

[cshold]

General cleaning of ajaxify cart styles

While working with a new theme, I noticed it was pretty difficult to override the ajax cart's styles. The drawer was defined with a dark colour scheme, and the modal was light. All colors were defined based on #ajaxifyModal or #ajaxifyDrawer, so overriding them was a specificity nightmare.

Ajax cart-related updates include:

• Prefix Sass mixin (for cleanliness)
• No more reliance on IDs for styles (except #ajaxifyCart-overlay)
• Modal and drawer styles are now the same
  • Styles are set with minimal Sass variables, which can be updated to match a store's theme settings or custom colours
• Removed general/unnecessary colors
• Moved the flip button styles below general cart styles
• Renamed some variables and mixins for less overlap and a cleaner naming convention
• Modal's overlay colour is now based on the modal's background

Other updates include:

• Renamed $borderColor to $colorBorder to match naming convention of other variables
• Added a background colour theme option

cc @shopify/fed @carolineschnapp

[richgilbank]

👍

[carolineschnapp]

That is wonderful!

[dan-menard]

Really nice cleanup. 👍 👍 👍