Synchronize RGB Hex values from official Nord palette

[ericvw]

Align the ANSI and other iTerm2 colors to the Nord color palette.

The following values have changed in the iTerm2 Settings > Profiles >
Colors panel, noting changes in colors:

Basic Colors
------------
- Foreground    (nord4): #d8dde8 -> #d8dee9
- Background    (nord0): #2e333f -> #2e3440
- Bold          (nord6): #eceef3 -> #eceff4
- Links         (nord5): #e5e8ef -> #e5e9f0
- Selection     (nord2): #4c5569 -> #434c5e
                         (nord3) -> (nord2)
- Selected text (nord4): #d8dde8 -> #d8dee9
- Tab color     (nord1): #3b4151 -> #3b4252

Cursor Colors
-------------
- Cursor       (nord4): #d8dde8 -> #d8dee9
- Cursor text  (nord1): #3b4151 -> #3b4252
- Cursor guide (nord2): #3b4151 -> #434c5e
                        (nord1)    (nord2)

ANSI Colors
-----------
- Normal Black     (nord1): #3b4151  -> #3b4252
- Bright Black     (nord3): #4c5569  -> #4c566a
- Normal Red      (nord11): #be6069  -> #bf616a
- Bright Red      (nord11): #be6069  -> #bf616a
- Normal Green    (nord14): #a3bd8b  -> #a3be8c
- Bright Green:   (nord14): #a3bd8b  -> #a3be8c
- Normal Yellow:  (nord13): #ebca8a  -> #ebcb8b
- Bright Yellow:  (nord12): #ebca8a  -> #d08770
                            (nord13)    (nord12)
- Normal Blue:     (nord9): #81a0c0  -> #81a1c1
- Bright Blue:    (nord10): #81a0c0  -> #5e81ac
                            (nord9)     (nord10)
- Normal Magenta: (nord15): #b48dac  -> #b48ead
- Bright Magenta: (nord15): #b48dac  -> #b48ead
- Normal Cyan:     (nord8): #88bfcf  -> #88c0d0
- Bright Cyan:     (nord7): #8fbbba  -> #8fbcbb
- Normal White:    (nord5): #e5e8ef  -> #e5e9f0
- Bright White:    (nord6): #eceef3  -> #eceff4

The text selection and cursor guide uses nord2 now to align with
"currently active text editor line as well as selection."

Bright Blue uses nord10, the next accent level, for tertiary UI
elements. Using nord12 may be a stretch for Bright Yellow. With both
these changes, all of Frost and Aurora are available.

Closes: #15

[ericvw]

I noticed the change from "Calibrated" to "sRGB" in the diff, which caused me to research this further.

According to mbadolato/iTerm2-Color-Schemes#349 (comment), the maintainer of iTerm2 recommends sRGB (P3 is not available until iTerm 3.5). Leaving it unspecified or explicitly "Calibrated" is device-specific, which may render differently on other users' displays. By keeping it sRGB and having the RGB Hex values match, each display can calibrate against the sRGB standard values as needed.

[ericvw]

I've updated the commit and included the text in the PR description to describe the details of the changes to help facilitate review and discussion.

[ericvw]

Here is what the iTerm2 Colors settings look like with the changes in this PR.

[svengreb]

Hi @ericvw 👋, thanks for your contribution and the very detailed PR description and research 👍

I could vaguely remember the topic about the color space (sRGB vs. Calibrated) and found a comment from myself in PR #8, which is still open.
Based on your research I'll revisit my findings about this topic, but the arguments of the iTerm2 author himself that you linked to is more or less the best source 😄

I'll review this PR as soon as nordtheme/nord#185 is completed which has the most priority right now to finalize the nordtheme organization migration as finally retire Arctic Ice Studio as Nord and personal brand.

[sa7mon]

Hi, can this be reviewed?

[clach04]

@ericvw I'm not an iTerm2 user (I don't have a Mac) but just wanted to say (belated) thank you for the clear PR and explanation text. This is useful for other terminal users.

You rock! 🏆

[clach04]

@ericvw I think the blue colors in your explanation are switched:

• Normal Blue: (nord9): #81a0c0 -> #81a1c1
• Bright Blue: (nord10): #81a0c0 -> #5e81ac
  (nord9) (nord10)

Taking your comments and placing them into Putty I get:

Switching the two blues I get:

Which I think is easier to read (see some of the directory names). Obviously, it's a personal opinion, so no wrong answers here :-). But thank you again for the notes.

[ericvw]

@clach04, There is an interaction between the colors specified in the terminal emulator and those derived from dircolors, which affects the output of color-supported ls.

My attempt with the colors for iTerm2 was to have some differentiating colors between regular and bright blue; I don't have a strong opinion on which ones should be chosen. However, you bring up a good point that the terminal colors chosen should be in harmony with dircolors.

I believe my dircolors setup is based primarily on the Solarized project, which doesn't utilize many background colors for ls, which is why I have yet to come across blue text against a green background.

[clach04]

@ericvw yeah dir_colors is a whole minefield of its own, I've been putting off customizing this for a while :-)

When I'm assessing a theme for a terminal the first thing I check is text with pyshow_colors2.py script and then directory colors - before I get into tools like vim. It just so happened that the dircolors is what made be notice this initially

The big thing that convinced me they were reversed/switched was the little bar chart.

Here is the default Putty color scheme:

Note the bottom row is a lighter version of the darker top row.

For the Nord theme, blue is reversed:

[ericvw]

@clach04, I revisited your idea of switching the normal and bright blue colors and gave this more thought.

It makes sense that the lighter version of the colors should be the bright variant — it makes logical sense.

However, when I switched the blue colors around, vim and neovim were incorrect because the Nordtheme ports expect nord9 to be normal blue. Otherwise, the guidance specified in https://www.nordtheme.com/docs/colors-and-palettes is broken.

While I agree in spirit that the blues should be switched, where nord9 is the bright blue variant, in practice, this seems like a more significant hurdle because all the other CLI Nordtheme ports would need to be updated accordingly to be in harmony with how the terminal colors are specified.

[clach04]

That makes total sense @ericvw , that would be a lot of other changes!