Make dark mode Google-branded instead of YouTube-branded

The dark theme was a YouTube pastiche: red accents, near-black surfaces, and
applyTheme() swapped the Google wordmarks for the YouTube logo pointing at
youtube.com. Drop the swap so the bio logos stay Google in both themes, and
recolour the palette to Google's Material dark values (#8ab4f8 on #202124),
including lightened red/yellow/green so the four-colour section bar and the
rotating academic dots read on dark instead of being overridden to #ff0000.

youtube_logo.svg had no other references, so it goes with it. The YouTube link
under Publications is a real talk recording and stays.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Author: zlyfunction

index.html

@@ -51,50 +51,43 @@
             --radius-pill: 999px;
         }
 
-        /* ── YouTube-style dark theme ── */
+        /* ── Google-style dark theme ── */
         [data-theme="dark"] {
-            /* YouTube red theme — softer, low-saturation red for links/accents */
-            --google-blue: #e08a83;
-            --google-blue-hover: #ee9f98;
-            --google-blue-light: rgba(224, 138, 131, 0.16);
-
-            --color-bg: #0f0f0f;
-            --color-surface: #181818;
-            --color-surface-variant: #212121;
-            --color-surface-tonal: #272727;
-            --color-text: #f1f1f1;
-            --color-text-secondary: #aaaaaa;
-            --color-text-tertiary: #717171;
-            --color-accent: #e08a83;
-            --color-accent-light: #ee9f98;
-            --color-border: #3f3f3f;
-            --color-border-light: #272727;
-            --color-highlight: rgba(224, 138, 131, 0.16);
-            --color-award: #ffd24d;
-            --color-award-bg: rgba(255, 210, 77, 0.14);
+            /* Google brand colors, lightened for dark surfaces */
+            --google-blue: #8ab4f8;
+            --google-blue-hover: #aecbfa;
+            --google-blue-light: rgba(138, 180, 248, 0.16);
+            --google-red: #f28b82;
+            --google-yellow: #fdd663;
+            --google-green: #81c995;
+
+            --color-bg: #202124;
+            --color-surface: #202124;
+            --color-surface-variant: #28292c;
+            --color-surface-tonal: #303134;
+            --color-text: #e8eaed;
+            --color-text-secondary: #9aa0a6;
+            --color-text-tertiary: #80868b;
+            --color-accent: #8ab4f8;
+            --color-accent-light: #aecbfa;
+            --color-border: #3c4043;
+            --color-border-light: #2d2e31;
+            --color-highlight: rgba(138, 180, 248, 0.16);
+            --color-award: #fdd663;
+            --color-award-bg: rgba(253, 214, 99, 0.14);
             --color-card-shadow: rgba(0, 0, 0, 0.6);
             --color-card-shadow-soft: rgba(0, 0, 0, 0.4);
         }
 
         [data-theme="dark"] nav {
-            background: rgba(15, 15, 15, 0.92);
-            border-bottom-color: #272727;
-        }
-
-        /* YouTube red accent bar in place of the Google four-color gradient */
-        [data-theme="dark"] .section-title::before {
-            background: #ff0000;
-        }
-
-        /* YouTube red dot before the first academic group (Teaching Assistant) */
-        [data-theme="dark"] .academic-group:nth-of-type(1) .academic-subtitle::before {
-            background: #ff0000;
+            background: rgba(32, 33, 36, 0.92);
+            border-bottom-color: #2d2e31;
         }
 
         /* Neutral dark chips behind the colorful illustration icons */
         [data-theme="dark"] .funfact-icon,
         [data-theme="dark"] .misc-card-icon {
-            background: #272727;
+            background: #303134;
         }
 
         /* Brighten Go-board lines so they read on dark */
@@ -1359,16 +1352,6 @@
         function applyTheme(theme) {
             var dark = theme === 'dark';
             document.documentElement.setAttribute('data-theme', dark ? 'dark' : 'light');
-            // Swap Google branding for YouTube branding in dark mode
-            document.querySelectorAll('.bio-logo-google').forEach(function (img) {
-                img.src = dark ? './youtube_logo.svg' : './google_logo.png';
-                img.alt = dark ? 'YouTube' : 'Google';
-                var link = img.closest('a.logo-link');
-                if (link) {
-                    link.href = dark ? 'https://www.youtube.com/' : 'https://about.google/';
-                    link.setAttribute('aria-label', dark ? 'YouTube' : 'Google');
-                }
-            });
             // Swap the thesis illustration for its dark-mode version
             var thesis = document.getElementById('thesis-img');
             if (thesis) {