.structure-textarea {
    min-height: 220px;
    font-family: Consolas, "Courier New", monospace;
    font-size: 0.9rem;
    line-height: 1.5;
}

.structure-summary {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem 1.5rem;
    font-size: 0.9rem;
    color: #495057;
}

.structure-summary strong {
    color: #212529;
}

.structure-output {
    border: 1px solid #dee2e6;
    border-radius: 0.375rem;
    background: #fff;
    padding: 0.75rem 1rem;
    min-height: 200px;
    max-height: 70vh;
    overflow: auto;
    font-family: Consolas, "Courier New", monospace;
    font-size: 0.9rem;
    line-height: 1.55;
}

.structure-empty {
    color: #6c757d;
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

.structure-output ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.structure-output ul ul {
    margin-left: 0.55rem;
    padding-left: 1.1rem;
    border-left: 1px solid #ced4da;
}

.structure-node {
    position: relative;
}

.structure-node > ul {
    display: none;
}

.structure-node.is-open > ul {
    display: block;
}

.structure-line {
    display: flex;
    align-items: baseline;
    padding: 0.1rem 0.35rem;
    border-radius: 0.25rem;
    white-space: nowrap;
}

.structure-node.has-children > .structure-line {
    cursor: pointer;
}

.structure-node.has-children > .structure-line:hover {
    background: #f1f3f5;
}

.structure-toggle {
    display: inline-block;
    width: 0.9rem;
    flex: 0 0 0.9rem;
    margin-right: 0.35rem;
    position: relative;
    height: 0.9rem;
    align-self: center;
    user-select: none;
}

.structure-node.has-children > .structure-line > .structure-toggle::before {
    content: "";
    position: absolute;
    left: 0.2rem;
    top: 0.2rem;
    width: 0.4rem;
    height: 0.4rem;
    border-right: 1.5px solid #6c757d;
    border-bottom: 1.5px solid #6c757d;
    transform: rotate(-45deg);
    transition: transform 0.12s ease;
}

.structure-node.has-children.is-open > .structure-line > .structure-toggle::before {
    transform: rotate(45deg);
    top: 0.1rem;
}

.structure-tag {
    color: #0d47a1;
    font-weight: 600;
}

.structure-attr {
    color: #6f42c1;
    font-weight: 400;
}

.structure-attr-value {
    color: #198754;
}

.structure-text {
    color: #6c757d;
    font-style: italic;
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    font-size: 0.85rem;
}

.structure-comment {
    color: #adb5bd;
    font-style: italic;
}

.structure-count {
    color: #adb5bd;
    font-size: 0.75rem;
    margin-left: 0.25rem;
}

.structure-node.is-open > .structure-line > .structure-count {
    display: none;
}

@media (max-width: 767.98px) {
    .structure-output {
        font-size: 0.82rem;
        padding: 0.5rem 0.6rem;
    }

    .structure-output ul ul {
        padding-left: 0.8rem;
    }
}