FIX: Dark theme styling fixes

[AakashGfude]

fixes #227

The screenshot of fixes are (ordering based on issue #227 ):

3. I feel the images look better this way in dark mode. If the background is white, its too bright and defeats the purpose of dark-theme. What do you think @mmcky @HumphreyYang

cc: @HumphreyYang @mmcky

[codecov]

Codecov Report

Merging #228 (3db47b5) into master (3241d53) will not change coverage.
The diff coverage is n/a.

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[HumphreyYang]

Many thanks @AakashGfude, this looks even better!

I feel the images look better this way in dark mode. If the background is white, its too bright and defeats the purpose of dark-theme. What do you think @mmcky @HumphreyYang

The one in the screenshot looks great to me!

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I am also curious if we need a new QuantEcon logo for dark mode:

Perhaps with white text?

I also spotted some images without being in the dark mode in this lecture

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There are small edge cases for the top right buttons:

1. The text colour for the launch methods is slightly too close to the background:

2. I distantly remember the "Download PDF" button would take us to the PDF build of this lecture before instead of calling the print function of the browser (please correct me if I were wrong):

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One small question about styling I have is whether we want to show code output slightly more different from code cells:

In light mode, we have very distinctive cells and outputs:

but it looks very similar in dark mode:

Hope this helps : )

[AakashGfude]

Thanks @HumphreyYang , I think we will have to create a new image for that.

1. Have done the text method for the launch

2. "Download PDF" does print for single page, and our own compiled pdf for books. The books one is available only when a build has been run and included. Which is not done here.

3. This should be okay?

[HumphreyYang]

Thanks @HumphreyYang , I think we will have to create a new image for that.

1. Have done the text method for the launch

2. "Download PDF" does print for single page, and our own compiled pdf for books. The books one is available only when a build has been run and included. Which is not done here.
3. This should be okay?

Many thanks @AakashGfude, these look great to me!