Added a left border to the "+" button and reduced its horizontal padding to 3px using inline styles. The button now appears more compact and visually connected to the group tabs while remaining clearly separated on the right side.

Reduced the group button horizontal padding to 6px using inline styles and added overflow-x-auto to the group tabs container to make it horizontally scrollable. Also added shrink-0 to both group buttons and the "+" button to prevent them from shrinking when the container overflows.