Remove the rounded-t Tailwind class from timeline bars so spike peaks render as sharp, flat-topped rectangles instead of rounded corners, making bucket boundaries clearer to read. Verified in the browser in both light and dark theme. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01XFUNZwCvz3kcod3352ZR2o