themes/docsy/assets/scss/_alerts.scss

// Style alert boxes.

.alert {
    font-weight: $font-weight-medium;
    background: $white;
    color: inherit;
    border-radius: 0;

    @each $color, $value in $theme-colors {
        &-#{$color} {
            & .alert-heading {
                color: $value;
            }

            border-style: solid;
            border-color: $value;
            border-width: 0 0 0 4px;
        }
    }
}