web/web_listview_custom_column/static/src/css/web_listview_custom_column.css

.openerp .oe_view_manager_custom_column
{
    height: 24px;
    line-height: 24px;
    display: inline-block;
    border: 1px solid #ababab;
    cursor: pointer;
    -moz-border-radius: 5px;
    -webkit-border-radius: 5px;
    border-radius: 5px;
    max-width: calc(100% - 200px);
}
.openerp .oe_view_manager_custom_column a
{
    padding: 1px 6px;
    color: #4c4c4c;
}
.openerp .oe_view_manager_custom_column a.active i
{
    text-shadow: 0 0 3px #ababab;
}
.openerp .oe_view_manager_custom_column select
{
    margin: 1px;
    background: transparent;
    max-width: calc(100% - 110px);
}
.openerp .oe_list th .oe_custom_column_remove,
.openerp .oe_list th .oe_custom_column_left,
.openerp .oe_list th .oe_custom_column_right
{
    color: #4c4c4c;
    font-size: smaller;
}
.openerp .oe_list th .oe_custom_column_remove:hover,
.openerp .oe_list th .oe_custom_column_left:hover,
.openerp .oe_list th .oe_custom_column_right:hover
{
    text-shadow: 0px 0px 1px;
}