.query-builder {
    .group-conditions {
        margin: @padding-small-vertical 0 @padding-small-vertical @padding-large-horizontal;
    }

    input.form-control.condition-value {
        width: unset;
        display: inline-block;
    }

    select.operator,
    select.field,
    select.comparator {
        display: inline-block;
        background-color: #fff;
    }

    select.operator,
    select.field {
        width: 80px;
    }

    select.comparator {
        width: 50px;
    }
}

.query-builder {
    .group-conditions {
        margin: @padding-small-vertical 0 @padding-small-vertical 30px;
    }

    .rules-list {
        padding: 0 0 0 30px;
        position: relative;

        > * {
            position: relative;

            &::before,
            &::after {
                position: absolute;
                left: -30px;
                width: 30px;
                height: ~"calc(50% + 6px)";
                border: solid @input-border;
                content: "";
            }

            &::before {
                border-width: 0 0 2px 2px;
                top: -6px;
            }

            &::after {
                border-width: 0 0 0 2px;
                top: 50%;
            }

            &:first-child::before {
                height: ~"calc(50% + 8px)";
                top: -6px;
            }

            &:last-child::after {
                display: none;
            }
        }
    }

    .group,
    .condition {
        position: relative;
        margin: @padding-small-vertical 0;
        border: 1px solid @gray-lighter;
        border-radius: @border-radius-small;
        padding: @padding-small-vertical @padding-small-horizontal;
    }

    .condition {
        background-color: #fff;
    }

    input.form-control.condition-value {
        width: unset;
        display: inline-block;
    }

    select.operator,
    select.field,
    select.comparator {
        display: inline-block;
        background-color: #fff;
        width: unset;
    }
}

Add lines to represent structure of query in UI.
Add lines to represent structure of query in UI.
