Celebrate the 20th birthday of Git

The first commit of Git, ever, was performed on Thu, 7 Apr 2005 15:13:13
-0700 and it is kind of constitutes the birth of Git itself, see:
https://web.git.kernel.org/pub/scm/git/git.git/commit/?id=e83c5163316f89bfbde7d9ab23ca2e25604af290

This means that April 7th, 2025 is the 20th birthday of Git. Let's
celebrate that by (temporarily!) changing the Git logo on Git's home
page in a subtle way.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

assets/js/application.js

@@ -32,6 +32,7 @@ const baseURLPrefix = (() => {
 $(document).ready(function() {
   BrowserFallbacks.init();
   DarkMode.init();
+  GitTurns20.init();
   Search.init();
   Dropdowns.init();
   Forms.init();
@@ -102,6 +103,19 @@ var BrowserFallbacks = {
 
 }
 
+var GitTurns20 = {
+  init: function() {
+    const today = new Date();
+    if (today.getFullYear() === 2025 && today.getMonth() === 3 && today.getDate() === 7) {
+      this.celebrate();
+    }
+  },
+
+  celebrate: function() {
+    document.documentElement.dataset.celebration = 'git-turns-20';
+  }
+};
+
 var Search = {
   searching: false,
   currentSearch: '',

assets/sass/application.scss

@@ -28,6 +28,7 @@ $baseurl: "{{ .Site.BaseURL }}{{ if (and (ne .Site.BaseURL "/") (ne .Site.BaseUR
 @import 'lists';
 @import 'about';
 @import 'dark-mode';
+@import 'git-turns-20';
 
 code {
   display: inline;

assets/sass/git-turns-20.css

@@ -0,0 +1,19 @@
+@mixin logo20($infix: '') {
+    img[alt="Git"] {
+        filter: unset;
+        content: url('./images/logo20' + $infix + '.svg');
+    }
+}
+
+:root[data-celebration="git-turns-20"] {
+    @include logo20
+    &[data-theme="dark"] {
+        @include logo20($infix: '.dark-mode')
+    }
+    @media screen and (prefers-color-scheme: dark) {
+        @include logo20
+        &:not([data-theme="light"]) {
+            @include logo20($infix: '.dark-mode')
+        }
+    }
+}