dark-mode: don't apply color filter on all images

The image on the /about/data-assurance page looked creepy with the color
filter. And because the image isn't bright anyway, remove the filter
from that image.

Signed-off-by: Toon Claes <[email protected]>

Author: To1ne

assets/sass/dark-mode.css

@@ -77,7 +77,7 @@
 
             // the images in the About section would be too dark
             body#about {
-                img:not([alt="Git"]) {
+                img:not(.no-filter) {
                     filter: brightness(0.9) contrast(0.6) invert(1);
                 }
 

content/about/data-assurance.html

@@ -17,7 +17,7 @@ <h2>Data Assurance</h2>
     checksum when checked back out. It's impossible to get anything out of Git
     other than the <strong>exact bits you put in</strong>.
     </p>
-    <img height="522" src="{{< relurl "images/[email protected]" >}}" width="628">
+    <img class="no-filter" height="522" src="{{< relurl "images/[email protected]" >}}" width="628">
     <p>
     It is also impossible to change any file, date, commit message, or any other
     data in a Git repository without changing the IDs of everything after it.

layouts/partials/header.html

@@ -1,6 +1,6 @@
 <header>
 
-  <a href="{{ relURL "" }}"><img src="{{ relURL "images/[email protected]" }}" width="110" height="46" alt="Git" /></a>
+  <a href="{{ relURL "" }}"><img src="{{ relURL "images/[email protected]" }}" width="110" height="46" alt="Git" class="no-filter" /></a>
   <span id="tagline"></span>
   <script type="text/javascript">
     const taglines = [