ant-design/style/components/datepicker/RangePicker.less

@input-box-height: 35px;

.@{calendar-prefix-cls}-range-picker-input {
  background-color: transparent;
  border: 0;
  height: 18px;
  line-height: 18px;
  width: 44%;

  &[disabled] {
    cursor: not-allowed;
  }
}

.@{calendar-prefix-cls}-range {
  width: 502px;
  overflow: hidden;

  &-part {
    width: 250px;
    position: relative;
  }

  &-left {
    float: left;
  }

  &-right {
    float: right;
  }

  &-middle {
    position: absolute;
    left: 50%;
    width: 20px;
    margin-left: -10px;
    text-align: center;
    height: @input-box-height;
    line-height: @input-box-height;
  }

  .@{calendar-prefix-cls}-date-input-wrap,
  .@{calendar-prefix-cls}-time-picker-wrap {
    width: 47%;
  }

  .@{calendar-prefix-cls}-time-picker-wrap {
    position: absolute;
    left: 50%;
  }
  .@{css-prefix}time-picker-input {
    width: 100%;
  }

  .@{calendar-prefix-cls}-input-wrap {
    height: @input-box-height;
  }
  .@{calendar-prefix-cls}-input {
    border: 1px solid @border-color-base;
    border-radius: @border-radius-base;
  }
  .@{calendar-prefix-cls}-input,
  .@{css-prefix}time-picker-input {
    padding: 1px 7px;
    height: @input-height-sm;
  }
  .@{css-prefix}time-picker-icon {
    display: none;
  }

  .@{calendar-prefix-cls}-calendar-body,
  .@{calendar-prefix-cls}-decade-panel-body,
  .@{calendar-prefix-cls}-year-panel-body,
  .@{calendar-prefix-cls}-month-panel-body {
    border-bottom: 1px solid #e9e9e9;
  }

  &.@{calendar-prefix-cls}-week-number {
    width: 574px;

    .@{calendar-prefix-cls}-range-part {
      width: 286px;
    }
  }

  .@{calendar-prefix-cls}-year-panel,
  .@{calendar-prefix-cls}-month-panel {
    top: @input-box-height;
  }
  .@{calendar-prefix-cls}-month-panel .@{calendar-prefix-cls}-year-panel {
    top: 0;
  }
  .@{calendar-prefix-cls}-decade-panel-table,
  .@{calendar-prefix-cls}-year-panel-table,
  .@{calendar-prefix-cls}-month-panel-table {
    height: 208px;
  }

  .@{calendar-prefix-cls}-in-range-cell {
    background: tint(@primary-color, 90%);
    border-radius: 0;
  }

  &-bottom {
    text-align: right;
  }
  .@{calendar-prefix-cls}-ok-btn {
    position: static;
    margin: 7px 9px 9px;
  }
  .@{calendar-prefix-cls}-today-btn {
    margin: 9px;
  }
}