Height select 2 in bootstrap 3.3.4
/**
* Change three lines
*
/* line 11 */
.select2-container .select2-selection--single {
box-sizing: border-box;
cursor: pointer;
display: block;
height: 34px;
user-select: none;
-webkit-user-select: none; }
/* line 131 */
.select2-container--default .select2-selection--single .select2-selection__rendered {
color: #444;
line-height: 32px; }
/* line 139 */
.select2-container--default .select2-selection--single .select2-selection__arrow {
height: 32px;
position: absolute;
top: 1px;
right: 1px;
width: 20px; }