:root{color-scheme:light;font-family:Inter,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;background:#eceff3;color:#172033;--bg-page: #eceff3;--bg-surface: #ffffff;--bg-surface-soft: #f8fafc;--bg-muted: #eef3f9;--bg-selected: #e0ecff;--bg-hover: #f3f7fd;--text-primary: #172033;--text-secondary: #5e6b82;--text-muted: #7d8aa3;--border: #d9e1ec;--border-strong: #c5d2e3;--shadow: none;--accent: #2f6fed;--accent-soft: #eaf1ff;--danger-soft: #fff1f2;--danger-border: #fecdd3}*{box-sizing:border-box}html,body{margin:0;min-width:320px;min-height:100vh;overflow:hidden;background:var(--bg-page)}button,input,textarea,select{font:inherit}button{border:1px solid var(--border);background:var(--bg-surface);color:var(--text-primary);cursor:pointer;transition:background .18s ease,border-color .18s ease,color .18s ease,transform .18s ease}button:hover:not(:disabled){background:var(--bg-hover);border-color:var(--border-strong)}button:disabled{opacity:.55;cursor:not-allowed}#root{height:100vh}.app-shell{height:100vh;display:flex;flex-direction:column;gap:16px;padding:24px;overflow:hidden}.dialogue-panel,.explorer-panel,.viewer-panel,.error-banner{background:#fffffff0;border:1px solid var(--border);box-shadow:var(--shadow)}.app-toolbar{margin-bottom:16px}.app-toolbar .kb-selector{max-width:460px}.panel-header h2{margin:0}.panel-header p,.tree-hint,.viewer-placeholder p,.grid-card-meta{color:var(--text-secondary)}.kb-selector{display:flex;flex-direction:column;gap:8px;max-width:460px}.kb-selector-label{font-size:13px;font-weight:600;color:var(--text-primary)}.kb-selector-input{border-radius:14px;border:1px solid var(--border);background:var(--bg-surface);color:var(--text-primary);padding:12px 14px}.error-banner{border-radius:16px;padding:14px 16px;margin-bottom:16px;color:#be123c;background:var(--danger-soft);border-color:var(--danger-border)}.visually-hidden{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.app-main{display:grid;grid-template-columns:minmax(260px,1fr) minmax(520px,2fr);gap:16px;flex:1;min-height:0}.dialogue-panel,.explorer-panel,.viewer-panel{display:flex;flex-direction:column;border-radius:24px;overflow:hidden;min-height:0}.dialogue-panel{background:#ffffffd1}.panel-header{display:flex;justify-content:space-between;align-items:center;gap:20px;padding:20px 22px;border-bottom:1px solid var(--border)}.panel-header-stack{align-items:flex-start}.explorer-toolbar{display:flex;flex-wrap:wrap;align-items:center;justify-content:flex-end;gap:12px;min-width:0}.toolbar{display:flex;gap:10px;justify-content:flex-end}.view-toggle button,.ghost-button{border-radius:12px;padding:10px 14px}.view-toggle{display:inline-flex;gap:6px}.toolbar 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22px;overflow:auto;min-height:0}.explorer-selection-surface{position:relative;min-height:100%}.explorer-pathbar{display:flex;align-items:center;gap:14px;margin-bottom:18px}.explorer-path-actions{display:inline-flex;align-items:center;gap:10px}.explorer-breadcrumbs{display:flex;align-items:center;flex-wrap:wrap;gap:6px;min-width:0}.explorer-breadcrumb-segment{display:inline-flex;align-items:center;gap:6px;min-width:0}.breadcrumb-separator{color:var(--text-muted)}.breadcrumb-button{border:none;background:transparent;padding:0;color:var(--text-secondary)}.breadcrumb-button.is-current{color:var(--text-primary);font-weight:600}.explorer-selection-surface.surface-upload-target{border-radius:20px;background:#2f6fed0d}.tree-list{list-style:none;margin:0;padding:0}.tree-item+.tree-item{margin-top:8px}.tree-row{display:flex;align-items:center;gap:6px;border-radius:14px;transition:background .18s 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var(--border-strong);border-radius:18px;padding:18px;color:var(--text-secondary);background:var(--bg-surface-soft)}.viewer-body.is-empty{padding:0}.viewer-modal-backdrop{position:fixed;top:0;right:0;bottom:0;left:0;z-index:50;display:flex;align-items:center;justify-content:center;padding:32px;background:#0f172a38;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px)}.viewer-modal{width:min(960px,100%);height:min(78vh,860px)}.viewer-modal-close{width:40px;height:40px;border-radius:12px;padding:0;border:none;background:transparent}.inline-loading{margin-top:8px;margin-left:18px}.drop-target-hint{margin-right:10px;color:var(--accent);font-size:12px;font-weight:600}.selection-marquee{position:absolute;z-index:2;border:1px solid rgba(47,111,237,.85);background:#2f6fed24;border-radius:12px;pointer-events:none}.grid-view{display:flex;flex-direction:column;gap:0}.grid-cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(160px,1fr));gap:14px}.grid-card{display:flex;flex-direction:column;align-items:flex-start;gap:10px;min-height:140px;padding:16px;border-radius:18px;background:var(--bg-surface);text-align:left}.grid-card.selected{background:var(--bg-selected);border-color:#a9c6ff}.grid-card-icon{color:var(--text-secondary)}.grid-card-name{font-weight:600;color:var(--text-primary);overflow-wrap:anywhere}.grid-card-thumbnail{position:relative;width:100%;aspect-ratio:16 / 10;overflow:hidden;border-radius:14px;background:var(--bg-surface-soft);border:1px solid var(--border)}.grid-card-thumbnail 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Mono,Menlo,monospace;font-size:13px}.text-viewer{margin:0;white-space:pre-wrap;overflow-wrap:anywhere}@media(max-width:1120px){.panel-header{flex-direction:column;align-items:flex-start}.explorer-toolbar{width:100%;min-width:0;align-items:flex-start;justify-content:flex-start}.toolbar{justify-content:flex-start}.explorer-pathbar{flex-direction:column;align-items:flex-start}}@media(max-width:980px){.app-main{grid-template-columns:1fr}.dialogue-panel{min-height:180px}.viewer-modal-backdrop{padding:16px}.viewer-modal{height:min(84vh,860px)}}