CB templates that have images for Tab backgrounds have a set width. This can be fixed using the default CB template or a CB template that does not have images for backgrounds. Based on the image you're using Luna template. Please see the below CSS responsible for tabs.
Selected Tab
IN: components/com_comprofiler/plugin/templates/luna/template.css
ON: Line 213
Code:
.dynamic-tab-pane-control .tab-row .tab.selected, .dynamic-tab-pane-control .tab-row .tab.selected:hover {
background: url("tab.active.png") no-repeat scroll 0 0 transparent;
border-bottom-width: 0;
font: 11px Tahoma,sans-serif;
height: 18px;
margin: 1px -3px -1px 0;
padding: 2px 0 0;
top: -2px;
width: 74px;
z-index: 3;
}
Non-selected Tab
IN: components/com_comprofiler/plugin/templates/luna/template.css
ON: Line 185
Code:
.dynamic-tab-pane-control .tab-row .tab {
background: url("tab.png") no-repeat scroll 0 0 transparent;
border: 0 none;
cursor: default;
display: inline;
float: left;
font: 11px Tahoma,sans-serif;
height: 16px;
margin: 1px -1px 1px 2px;
overflow: hidden;
padding: 2px 0 0;
position: relative;
text-align: center;
top: 0;
white-space: nowrap;
width: 70px;
z-index: 1;
}