section[data-viewer-tool] .viewer-shell {
    display: grid;
    grid-template-columns: minmax(300px, 380px) minmax(0, 1fr);
    gap: 22px;
    align-items: start;
    margin-top: 22px;
}

section[data-viewer-tool] .viewer-panel,
section[data-viewer-tool] .viewer-preview-panel {
    background: var(--bg-surface-glass);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    padding: 24px;
}

section[data-viewer-tool] .viewer-panel h3,
section[data-viewer-tool] .viewer-preview-panel h3 {
    display: flex;
    align-items: center;
    gap: 8px;
    margin: 0 0 10px;
    color: var(--text-main);
    font-size: 18px;
    font-weight: 800;
    line-height: 1.35;
}

section[data-viewer-tool] .viewer-dropzone {
    position: relative;
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-lg);
    min-height: 224px;
    padding: 42px 22px;
    text-align: center;
    background: var(--bg-surface-glass);
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    transition: border-color 0.2s ease, background 0.2s ease, transform 0.2s ease;
}

section[data-viewer-tool] .viewer-dropzone:hover,
section[data-viewer-tool] .viewer-dropzone:focus-within,
section[data-viewer-tool] .viewer-dropzone.dragover {
    border-color: var(--clr-teal);
    background: var(--bg-surface);
    transform: translateY(-1px);
}

section[data-viewer-tool] .viewer-dropzone i {
    display: block;
    margin-bottom: 14px;
    color: var(--clr-teal);
    font-size: 42px;
    pointer-events: none;
}

section[data-viewer-tool] .viewer-dropzone p {
    pointer-events: none;
}

section[data-viewer-tool] .viewer-dropzone .file-hidden-input {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
    z-index: 2;
}

section[data-viewer-tool] .viewer-meta-list {
    display: grid;
    gap: 10px;
    margin-top: 18px;
}

section[data-viewer-tool] .viewer-meta-item {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    align-items: center;
    min-height: 46px;
    padding: 11px 13px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: var(--input-bg);
    font-size: 13px;
}

section[data-viewer-tool] .viewer-meta-item strong {
    color: var(--text-muted);
    font-weight: 600;
    white-space: nowrap;
}

section[data-viewer-tool] .viewer-meta-item span {
    color: var(--text-main);
    text-align: right;
    word-break: break-all;
    font-weight: 700;
}

section[data-viewer-tool] .viewer-toolbar {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 16px;
}

section[data-viewer-tool] .viewer-actions {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    justify-content: flex-end;
}

section[data-viewer-tool] .viewer-tabs {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    padding: 2px 0 12px;
}

section[data-viewer-tool] .viewer-tab {
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: var(--input-bg);
    color: var(--text-main);
    cursor: pointer;
    font-size: 13px;
    font-weight: 700;
    min-height: 36px;
    padding: 8px 12px;
    white-space: nowrap;
}

section[data-viewer-tool] .viewer-tab.active {
    border-color: var(--clr-teal);
    background: rgba(20, 184, 166, 0.12);
    color: var(--clr-teal);
}

section[data-viewer-tool] .viewer-search-row {
    display: grid;
    grid-template-columns: minmax(180px, 1fr) auto;
    gap: 10px;
    margin-bottom: 14px;
}

section[data-viewer-tool] .viewer-search-row input {
    min-height: 40px;
    width: 100%;
    padding: 0 12px;
    border: 1px solid var(--input-border);
    border-radius: var(--radius-sm);
    background: var(--input-bg);
    color: var(--text-main);
}

section[data-viewer-tool] .viewer-preview-surface {
    min-height: 520px;
    max-height: 760px;
    overflow: auto;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-surface);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.35);
}

section[data-viewer-tool] .viewer-empty {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 520px;
    padding: 30px;
    text-align: center;
    color: var(--text-muted);
}

section[data-viewer-tool] .viewer-document {
    width: min(100%, 820px);
    min-height: 420px;
    margin: 22px auto;
    padding: clamp(20px, 4vw, 42px);
    background: #ffffff;
    border: 1px solid #e5e7eb;
    box-shadow: 0 12px 32px rgba(15, 23, 42, 0.10);
    color: #111827;
    font-family: "Noto Sans KR", sans-serif;
    line-height: 1.75;
    white-space: pre-wrap;
    word-break: keep-all;
    overflow-wrap: anywhere;
}

section[data-viewer-tool] .viewer-slide {
    width: min(100%, 860px);
    aspect-ratio: 16 / 9;
    margin: 22px auto;
    padding: clamp(22px, 4vw, 44px);
    background: linear-gradient(135deg, #0f172a, #334155);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 8px;
    box-shadow: 0 18px 38px rgba(15, 23, 42, 0.22);
    color: #ffffff;
    font-size: clamp(16px, 2vw, 24px);
    line-height: 1.55;
    white-space: pre-wrap;
    overflow: auto;
}

section[data-viewer-tool] .viewer-table {
    width: max-content;
    min-width: 100%;
    border-collapse: separate;
    border-spacing: 0;
    font-size: 13px;
}

section[data-viewer-tool] .viewer-table th,
section[data-viewer-tool] .viewer-table td {
    min-width: 96px;
    max-width: 280px;
    border-right: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
    padding: 8px 10px;
    text-align: left;
    vertical-align: top;
    white-space: pre-wrap;
    word-break: break-word;
    background: var(--bg-surface);
}

section[data-viewer-tool] .viewer-table thead th {
    position: sticky;
    top: 0;
    z-index: 2;
    background: var(--input-bg);
    color: var(--text-muted);
    font-weight: 800;
    text-align: center;
}

section[data-viewer-tool] .viewer-canvas-list {
    display: grid;
    gap: 18px;
    padding: 18px;
    justify-items: center;
}

section[data-viewer-tool] .viewer-canvas-list canvas,
section[data-viewer-tool] .viewer-canvas-list img {
    max-width: 100%;
    background: #ffffff;
    border: 1px solid #e5e7eb;
    border-radius: 6px;
    box-shadow: 0 10px 24px rgba(15, 23, 42, 0.14);
}

section[data-viewer-tool] .viewer-svg-frame {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 520px;
    padding: 18px;
    background:
        linear-gradient(45deg, #f3f4f6 25%, transparent 25%),
        linear-gradient(-45deg, #f3f4f6 25%, transparent 25%),
        linear-gradient(45deg, transparent 75%, #f3f4f6 75%),
        linear-gradient(-45deg, transparent 75%, #f3f4f6 75%);
    background-color: #ffffff;
    background-position: 0 0, 0 10px, 10px -10px, -10px 0;
    background-size: 20px 20px;
}

section[data-viewer-tool] .viewer-svg-frame img {
    max-width: 100%;
    max-height: 700px;
}

section[data-viewer-tool] .viewer-detail-box {
    margin-top: 12px;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: var(--input-bg);
    color: var(--text-muted);
    font-size: 13px;
    line-height: 1.6;
}

section[data-viewer-tool] .viewer-metadata-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 10px;
    padding: 18px;
}

section[data-viewer-tool] .viewer-metadata-card {
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: var(--input-bg);
    padding: 14px;
}

section[data-viewer-tool] .viewer-metadata-card strong {
    display: block;
    margin-bottom: 6px;
    color: var(--text-muted);
    font-size: 12px;
}

section[data-viewer-tool] .viewer-metadata-card span {
    color: var(--text-main);
    font-size: 15px;
    font-weight: 800;
}

@media (max-width: 960px) {
    .viewer-shell {
        grid-template-columns: 1fr;
    }

    .viewer-toolbar {
        flex-direction: column;
    }

    .viewer-actions {
        justify-content: flex-start;
    }

    .viewer-search-row {
        grid-template-columns: 1fr;
    }

    .viewer-preview-surface,
    .viewer-empty,
    .viewer-svg-frame {
        min-height: 420px;
    }
}