feat: update theme colours (#6)

### Explanation

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### Issue

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### Attestations

- [ ] I have read and agree to the [Code of Conduct](https://docs.nhcarrigan.com/community/coc/)
- [ ] I have read and agree to the [Community Guidelines](https://docs.nhcarrigan.com/community/guide/).
- [ ] My contribution complies with the [Contributor Covenant](https://docs.nhcarrigan.com/dev/covenant/).

### Dependencies

- [ ] I have pinned the dependencies to a specific patch version.

### Style

- [ ] I have run the linter and resolved any errors.
- [ ] My pull request uses an appropriate title, matching the conventional commit standards.
- [ ] My scope of feat/fix/chore/etc. correctly matches the nature of changes in my pull request.

### Tests

- [ ] My contribution adds new code, and I have added tests to cover it.
- [ ] My contribution modifies existing code, and I have updated the tests to reflect these changes.
- [ ] All new and existing tests pass locally with my changes.
- [ ] Code coverage remains at or above the configured threshold.

### Documentation

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### Versioning

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Reviewed-on: #6
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

src/index.ts

@@ -11,7 +11,7 @@ console.log(`
 Loading NHCarrigan library v${nhcarriganHeadersVersion}.
 Copyright (c) ${new Date().getFullYear().
   toString()} NHCarrigan
-Changelog: https://codeberg.org/nhcarrigan/website-headers/releases
+Changelog: https://git.nhcarrigan.com/nhcarrigan/website-headers/releases
 Licensed under our public license: https://docs.nhcarrigan.com/legal/license
 Questions? Contact us at https://docs.nhcarrigan.com/about/contact
 ========================================
@@ -136,8 +136,8 @@ nhcarriganHeadersStyles.innerHTML = `
 }
 
 :root {
-  --foreground: #2a0a18;
-  --background: #ffb6c1bb;
+  --foreground: #8F2447;
+  --background: #E1F6F9DC;
 }
 
 * {
@@ -251,8 +251,8 @@ a {
   color: var(--background);
 }
 .is-dark {
-  --foreground: #ffb6c1;
-  --background: #2a0a18bb;
+  --foreground: #E1F6F9;
+  --background: #8F2447bb;
 }
 @media screen and (max-width: 625px) {
   #tree-nation-offset-website {