web/src-web/src/theme/theme-base/components/data/_tree.scss
.p-tree {
    border: $panelContentBorder;
    background: $panelContentBg;
    color: $panelContentTextColor;
    padding: $panelContentPadding;
    border-radius: $borderRadius;

    .p-tree-container {
        .p-treenode {
            padding: $treeNodePadding;

            .p-treenode-content {
                border-radius: $borderRadius;
                transition: $listItemTransition;
                padding: $treeNodeContentPadding;

                .p-tree-toggler {
                    margin-right: $inlineSpacing;
                    @include action-icon();
                }

                .p-treenode-icon {
                    margin-right: $inlineSpacing;
                    color: $treeNodeIconColor;
                }

                .p-checkbox {
                    margin-right: $inlineSpacing;

                    .p-indeterminate {
                        .p-checkbox-icon {
                            color: $textColor;
                        }
                    }
                }

                &:focus {
                    @include focused-listitem();
                }

                &.p-highlight {
                    background: $highlightBg;
                    color: $highlightTextColor;

                    .p-tree-toggler,
                    .p-treenode-icon {
                        color: $highlightTextColor;

                        &:hover {
                            color: $highlightTextColor;
                        }
                    }
                }

                &.p-treenode-selectable:not(.p-highlight):hover {
                    background: $inputListItemHoverBg;
                    color: $inputListItemTextHoverColor;
                }

                &.p-treenode-dragover {
                    background: $inputListItemHoverBg;
                    color: $inputListItemTextHoverColor;
                }
            }
        }
    }

    .p-tree-filter-container {
        margin-bottom: $inlineSpacing;

        .p-tree-filter {
            width: 100%;
            padding-right: nth($inputPadding, 2) + $primeIconFontSize;
        }

        .p-tree-filter-icon {
            right: nth($inputPadding, 2);
            color: $inputIconColor;
        }
    }

    .p-treenode-children {
        padding: $treeNodeChildrenPadding;
    }

    .p-tree-loading-icon {
        font-size: $loadingIconFontSize;
        
        &.p-icon {
            width: $loadingIconFontSize;
            height: $loadingIconFontSize;
        }
    }

    .p-treenode-droppoint {
        height: $inlineSpacing;

        &.p-treenode-droppoint-active {
            background: scale-color($highlightBg, $lightness: -20%);
        }
    }
}
