select2/src/scss/core.scss

.s2-container {
  margin: 0;
  position: relative;
  zoom: 1;
  vertical-align: middle;

  &.s2-active {
    border: 1px solid #5897fb;
    border-top: bottom;
  }

  .s2-single-select {
    display: block;
    height: 26px;
    padding: 0 0 0 8px;
    overflow: hidden;
    position: relative;

    border: 1px solid #aaa;
    white-space: nowrap;
    line-height: 26px;
    color: #444;
    text-decoration: none;

    border-radius: 4px;

    background-clip: padding-box;

    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;

    background-color: #fff;
    background-image: -webkit-gradient(linear, left bottom, left top, color-stop(0, #eee), color-stop(0.5, #fff));
    background-image: -webkit-linear-gradient(center bottom, #eee 0%, #fff 50%);
    background-image: -moz-linear-gradient(center bottom, #eee 0%, #fff 50%);
    filter: progid:DXImageTransform.Microsoft.gradient(startColorstr = '#ffffff', endColorstr = '#eeeeee', GradientType = 0);
    background-image: linear-gradient(to top, #eee 0%, #fff 50%);

    .s2-selection {
      margin-right: 26px;
      display: block;
      overflow: hidden;

      white-space: nowrap;

      text-overflow: ellipsis;
    }
  }

  .s2-open {
    .select2-container-active .select2-choice,
    .select2-container-active .select2-choices {
      border: 1px solid #5897fb;
      outline: none;

      -webkit-box-shadow: 0 0 5px rgba(0, 0, 0, .3);
      box-shadow: 0 0 5px rgba(0, 0, 0, .3);
    }
  }

}

.s2-search {
  input {
    -webkit-box-sizing: border-box; /* webkit */
    -moz-box-sizing: border-box; /* firefox */
    box-sizing: border-box; /* css3 */
  }
}


.s2-dropdown {
  width: 100%;
  margin-top: -1px;
  position: absolute;
  z-index: 9999;
  overflow: scroll;

  background: #fff;
  color: #000;
  border: 1px solid #5897fb;
  border-top: none;

  border-radius: 0 0 4px 4px;

  -webkit-box-shadow: 0 4px 5px rgba(0, 0, 0, .15);
  box-shadow: 0 4px 5px rgba(0, 0, 0, .15);
}


.s2-hidden {
  display: none;
}