**Issue**: Only info and shortcuts buttons were showing orange color when
scrolled to bottom of page. Download PDF, Print Friendly, and Color Theme
buttons were missing this visual feedback.
**Fix**:
1. Added all buttons to at-bottom class logic in utils._hs:
- #download-button
- #print-friendly-button
- .color-theme-switcher
2. Added CSS .at-bottom styles for missing buttons:
- .download-btn.at-bottom
- .print-friendly-btn.at-bottom
- .color-theme-switcher.at-bottom
**Result**: All fixed buttons now show unified orange (#f39c12) background
when page is scrolled to bottom (within 50px), providing consistent visual
feedback across all controls.
Files changed:
- static/hyperscript/utils._hs: Added 3 buttons to scroll handler
- static/css/main.css: Added 2 .at-bottom styles
- static/css/color-theme.css: Added 1 .at-bottom style