src/css/_tooltips.scss
$tooltip-bg: #fff !default;

.abt-citation,
.abt-footnote {
    display: inline-block;
    cursor: pointer;
}

.tooltip-inner {
    z-index: 20;
    max-width: 350px;
    padding: 8px 10px;
    font-size: 12px;
    line-height: 1.5;
    border-radius: 3px;
    background: $tooltip-bg;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.2);
}

.tooltip-arrow {
    border: solid $tooltip-bg;
}

.tooltip {
    $arrow-size: 5px;
    cursor: initial;
    z-index: 1;

    .tooltip-arrow {
        width: 0;
        height: 0;
        position: absolute;
        margin: $arrow-size;
    }

    &[x-placement^='top'] {
        margin-bottom: $arrow-size;

        .tooltip-arrow {
            border-width: $arrow-size $arrow-size 0 $arrow-size;
            border-left-color: transparent;
            border-right-color: transparent;
            border-bottom-color: transparent;
            bottom: -$arrow-size;
            left: calc(50% - #{$arrow-size});
            margin-top: 0;
            margin-bottom: 0;
        }
    }

    &[x-placement^='right'] {
        margin-left: $arrow-size;

        .tooltip-arrow {
            border-width: $arrow-size $arrow-size $arrow-size 0;
            border-left-color: transparent;
            border-top-color: transparent;
            border-bottom-color: transparent;
            left: -$arrow-size;
            top: calc(50% - #{$arrow-size});
            margin-left: 0;
            margin-right: 0;
        }
    }

    &[x-placement^='bottom'] {
        margin-top: $arrow-size;

        .tooltip-arrow {
            border-width: 0 $arrow-size $arrow-size $arrow-size;
            border-left-color: transparent;
            border-right-color: transparent;
            border-top-color: transparent;
            top: -$arrow-size;
            left: calc(50% - #{$arrow-size});
            margin-top: 0;
            margin-bottom: 0;
        }
    }

    &[x-placement^='left'] {
        margin-right: $arrow-size;

        .tooltip-arrow {
            border-width: $arrow-size 0 $arrow-size $arrow-size;
            border-top-color: transparent;
            border-right-color: transparent;
            border-bottom-color: transparent;
            right: -$arrow-size;
            top: calc(50% - #{$arrow-size});
            margin-left: 0;
            margin-right: 0;
        }
    }
}
