UI updates

[dreamwhisper]

Updates CSS/Markup to improve UI/UX. Includes:

• some responsive improvements, including buttons & category tabs
• improvements to height of preview when a category is selected (preview height not subject to the tallest of all patterns)

How to test

1. Load Frost and view the patterns page at various responsive breakpoints.
2. Select a category and make sure the view looks good.
3. At various breakpoints, hover on pattern so buttons appear (Or force a focus and resize browser).

Example before and after:

Note: on the buttons, the icons just shrink or disappear with odd widths for now.

[mike-day]

Thanks for tackling this, @dreamwhisper! I think these are some nice changes to the feel of the UI. The buttons in particular just feel right like this IMO.

I noticed a few small hiccups. The first was already existing but relates to the idea of this PR in terms of UI improvement (proposed fix with #109 seems to play nicely with the work done here).

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The second I think was also an existing bug, but it's now noticeable with this PR. When changing categories, if a pattern preview is in view that was also in the previously selected category, the width for that preview does not update right away:

Note that the container width is full when Recipes is clicked, but the preview width itself remains at less than 50%.
Also, when switching from Columns to All Patterns, the "Section" pattern on the right remains at full width when it should have reduced.

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I have a few ideas for how to fix the second issue and will dive deeper tomorrow!

[dreamwhisper]

@mike-day You ok to merge this or do you want to work on that second issue first?

[mike-day]

@mike-day You ok to merge this or do you want to work on that second issue first?

IMO, that second issue is not a blocker by any means. Merge away!

[dreamwhisper]

Thanks @mike-day!