amis/scss/layout/_hbox.scss

.#{$ns}Hbox {
    display: table;
    table-layout: fixed;
    border-spacing: 0;
    width: 100%;
    height: 100%;
    &>.#{$ns}Hbox-col {
        display: table-cell;
        vertical-align: top;
        height: 100%;
        float: none;
    }
}

.#{$ns}FormHbox {
    margin-left: -15px;
    margin-right: -15px;
    >.#{$ns}Hbox>.#{$ns}Hbox-col {
        padding-left: 15px;
        padding-right: 15px;
        vertical-align: top;
        >.#{$ns}Form-group {
            margin-left: 0;
            margin-right: 0;
        }
        >.#{$ns}Form-group:last-child {
            margin-bottom: 0;
        }
    }
    &.#{$ns}Hbox--xs {
        margin-left: -5px;
        margin-right: -5px;
        >.#{$ns}Hbox>.#{$ns}Hbox-col {
            padding-left: 5px;
            padding-right: 5px;
        }
    }
    &.#{$ns}Hbox--sm {
        margin-left: -10px;
        margin-right: -10px;
        >.#{$ns}Hbox>.#{$ns}Hbox-col {
            padding-left: 10px;
            padding-right: 10px;
        }
    }
}

@include media-breakpoint-down(md) {
    .#{$ns}Hbox--autoSm {
        display: block;
        &>.#{$ns}Hbox-col {
            width: auto;
            height: auto;
            display: block;
            &.show {
                display: block !important;
            }
        }
        & .#{$ns}Vbox {
            height: auto;
        }
        & .cell-inner {
            position: static !important;
        }
    }
}

@include media-breakpoint-down(sm) {
    .#{$ns}Hbox--autoXs {
        display: block;
        &>.#{$ns}Hbox-col {
            width: auto;
            height: auto;
            display: block;
        }
        & .#{$ns}Vbox {
            height: auto;
        }
        & .cell-inner {
            position: static !important;
        }
    }
}