Mobile: center pinned post, pagination fixes, minor layout tweaks

- First (pinned) post on mobile: title and image centered
- Pagination: restored page counter on mobile, buttons above footer
- Typography and layout minor improvements

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

themes/hugo-theme-massively/assets/scss/main.scss

@@ -6,7 +6,7 @@
 @import 'libs/html-grid';
 @import 'libs/fixed-grid';
 @import 'font-awesome.min.css';
-@import url('https://fonts.googleapis.com/css?family=Merriweather:300,700,300italic,700italic|Source+Sans+Pro:900');
+@import url('https://fonts.googleapis.com/css2?family=Merriweather:ital,wght@0,300;0,700;1,300;1,700&family=Source+Sans+Pro:wght@900&display=swap');
 
 /*
 	Massively by HTML5 UP