Fix lightbox overflow on Renegade and Nomad mobile

align-items: center clips content at both ends when taller than viewport.
Switch to align-items: flex-start + overflow-y: auto so gate scrolls from top.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Videos/nomad-soul.html

@@ -196,8 +196,9 @@
             background-color: #0a0704;
             z-index: 1000;
             display: flex;
-            align-items: center;
+            align-items: flex-start;
             justify-content: center;
+            overflow-y: auto;
             padding: var(--space-8);
             opacity: 0;
             visibility: hidden;