Add IntelliJ Darcula Theme Suite (Dark, Light, High Contrast)

[vikashkrdeveloper]

This PR introduces a complete IntelliJ-style Darcula theme suite to Carbon. These new themes provide developers with a familiar, readable, and visually appealing code experience inspired by JetBrains IDEs.

What’s Included

• IntelliJ Dark – A modern dark theme with balanced contrast and refined syntax highlighting.
• IntelliJ Light – The default light theme from JetBrains IDEs, clean and minimal.
• IntelliJ High Contrast – Designed for accessibility with bold contrasts and sharper readability.
• IntelliJ Classic Light – A retro light theme for those who prefer the classic IntelliJ look.
• IntelliJ Darcula – The iconic dark theme based on the original JetBrains Darcula palette.
• IntelliJ Darcula Contrast – A variant of Darcula with enhanced contrast for improved legibility.

All six themes are defined in /lib/constants.js using Carbon’s theme format. Each has been tested locally to ensure accurate syntax highlighting, visual consistency, and contrast balance.

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Integration Tests

• No integration tests added - this change only affects theme configuration and UI appearance.

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Screenshots

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Closes #1577 (Referenced: #597 (comment))

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[scordio]

Hi @vikashkrdeveloper, thanks for picking this up!

Instead of naming all of them as Darcula, would it make sense to refer to IntelliJ directly?

Specifically, the IDE has:

So maybe you could name the themes accordingly, e.g.:

• IntelliJ Dark
• IntelliJ Light
• IntelliJ High Contrast
• IntelliJ Classic Light
• IntelliJ Darcula
• IntelliJ Darcula Contrast

(I see you added three out of the six available, so please consider only the appropriate suggestions 😉)

[vikashkrdeveloper]

Hi @scordio, thanks again for the helpful suggestion!

I've now added all six IntelliJ-based themes and renamed them to match the official JetBrains IDE labels:

• IntelliJ Dark
• IntelliJ Light
• IntelliJ High Contrast
• IntelliJ Classic Light
• IntelliJ Darcula
• IntelliJ Darcula Contrast

This should now fully reflect the naming scheme you referenced from IntelliJ’s editor preferences. Let me know if you'd like any tweaks or if I should split the additions! 😊

Hi @vikashkrdeveloper, thanks for picking this up!

Instead of naming all of them as Darcula, would it make sense to refer to IntelliJ directly?

Specifically, the IDE has:

So maybe you could name the themes accordingly, e.g.:

• IntelliJ Dark
• IntelliJ Light
• IntelliJ High Contrast
• IntelliJ Classic Light
• IntelliJ Darcula
• IntelliJ Darcula Contrast

(I see you added three out of the six available, so please consider only the appropriate suggestions 😉)

[scordio]

LGTM! 👍

[vikashkrdeveloper]

Thanks for the review! Let me know if there's anything else you'd like me to tweak. 😊

LGTM! 👍

[vikashkrdeveloper]

Hey @scordio,

Just checking in on this PR - thanks again for the review and the LGTM!

I’ve incorporated all the suggested changes and added the full IntelliJ theme suite as discussed.
Let me know if anything else is needed from my side to help move this forward. Happy to make any final tweaks! 😊

Excited to see this land in Carbon! 🚀