:root{
  --bg:#f6f7f9; --panel:#fff; --ink:#1b1f24; --muted:#6b7280; --border:#e3e6ea;
  --accent:#3b7dd8; --accent-bg:#eaf1fb; --warn:#b45309; --warn-bg:#fdf3e7; --ok:#166534; --ok-bg:#e9f6ee;
}
*{box-sizing:border-box}
html,body{height:100%;margin:0}
body{display:flex;flex-direction:column;font:14px/1.5 -apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;color:var(--ink);background:var(--bg)}
.btn{border:1px solid var(--border);background:var(--panel);border-radius:8px;padding:6px 10px;cursor:pointer;color:var(--ink);font:inherit}
.btn:hover:not(:disabled){border-color:var(--accent)}
.btn:disabled{opacity:.5;cursor:not-allowed}
.btn.sm{padding:4px 8px;font-size:13px}
.btn.wide,.btn.grow{flex:1}
.val{color:var(--muted);font-size:12px;min-width:26px;display:inline-block;text-align:right}
.muted{color:var(--muted);font-size:13px}
.banner{padding:8px 12px;font-size:13px}
.banner.warn{background:var(--warn-bg);color:var(--warn)}
.banner.ok{background:var(--ok-bg);color:var(--ok)}
.banner.hidden{display:none}

/* top status bar (read-only) */
.strip{display:flex;align-items:center;gap:10px;height:40px;padding:0 12px;background:var(--panel);border-bottom:1px solid var(--border);white-space:nowrap;overflow:hidden}
.strip .brand{font-weight:600}
.strip-sep{color:var(--muted)}
.strip-id{font-size:13px;color:var(--ink);overflow:hidden;text-overflow:ellipsis}
.strip-spacer{flex:1}
.icon-btn{border:1px solid var(--border);background:var(--panel);border-radius:6px;padding:2px 8px;cursor:pointer;color:var(--ink);font-size:15px;line-height:1.3}
.icon-btn:hover{border-color:var(--accent)}
.ro{font-size:12px;color:var(--muted);font-variant-numeric:tabular-nums}
.ro.accent{color:var(--accent)}
.ro.warn-text{color:var(--warn)}
.chips{display:flex;gap:4px}
.strip .chips{max-width:220px;overflow-x:auto}
.chip{display:inline-flex;align-items:center;justify-content:center;min-width:20px;height:20px;padding:0 6px;border-radius:5px;background:var(--accent-bg);color:var(--accent);font-size:11px}
.lang-switch{display:flex;gap:4px;flex:none}

/* main split: left rail + central stage */
.body{flex:1;display:grid;grid-template-columns:288px 1fr 264px;min-height:0}
body.rail-collapsed .body{grid-template-columns:0 1fr 264px}
body.rpanel-collapsed .body{grid-template-columns:288px 1fr 0}
body.rail-collapsed.rpanel-collapsed .body{grid-template-columns:0 1fr 0}
body.rail-collapsed .rail{display:none}
body.rpanel-collapsed .rpanel{display:none}
.stage{grid-column:2;min-width:0;display:flex;background:var(--bg)}
#view{flex:1;width:100%;height:100%;display:block;cursor:crosshair}

/* left rail */
.rail{grid-column:1;border-right:1px solid var(--border);background:var(--panel);padding:10px;overflow-y:auto;display:flex;flex-direction:column;gap:12px;min-height:0}
.rail-files{display:flex;gap:6px}
.seclbl{font-size:11px;color:var(--muted);margin-bottom:6px;display:flex;justify-content:space-between;align-items:baseline;gap:8px}
.sel-full{width:100%}
.stepper{display:flex;gap:5px;margin:7px 0}
.frame-list{max-height:158px;overflow-y:auto;overscroll-behavior:contain;border:1px solid var(--border);border-radius:8px}  /* ~5 rows (31px each) then scroll inside the box */
.frame-list.picking{outline:2px solid var(--accent);outline-offset:2px;border-radius:8px;background:var(--accent-bg)}
body.copy-picking .frm{cursor:copy}
.frm{display:flex;align-items:center;gap:6px;padding:5px 9px;border-radius:6px;color:var(--muted);cursor:pointer}
.frm:hover{background:var(--bg)}
.frm.done{color:var(--ink)}
.frm.active{background:var(--accent-bg);color:var(--accent);font-weight:500}
.frm-name{flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.frm-virtual .frm-name{font-style:italic}   /* computed view-only unit (perfusion) */
.loupe-tile.perf .cap{color:#e5484d}
.frm-b{font-size:11px;color:var(--muted)}
.frm.active .frm-b{color:var(--accent)}
.frm-star{color:#c9ccd2;font-size:15px;line-height:1;padding:0 1px}
.frm-star:hover{color:#e5a50a}
.frm-star.on{color:#e5a50a}
.ctl-row{display:flex;align-items:center;gap:8px;margin:6px 0}
.ctl-row>label{font-size:12px;color:var(--muted);min-width:64px}
.ctl-row input[type=range]{flex:1;min-width:0;accent-color:var(--accent)}
.ctl-row select{flex:1;accent-color:var(--accent)}
.btn-row{display:flex;gap:6px;margin-top:6px}
.check-row{display:flex;align-items:center;gap:6px;font-size:12px;color:var(--muted);margin:8px 0 4px}
.check-row input{accent-color:var(--accent)}
.hint{font-size:12px;line-height:1.6}

/* collapsible tool groups */
.grp{border:1px solid var(--border);border-radius:8px;padding:0 10px}
.grp>summary{list-style:none;display:flex;align-items:center;gap:7px;padding:9px 0;cursor:pointer;font-size:13px;color:var(--ink)}
.grp>summary::-webkit-details-marker{display:none}
.grp .chev{color:var(--muted);transition:transform .15s;display:inline-block;font-size:11px}
.grp[open]>summary .chev{transform:rotate(90deg)}
.grp-body{padding-bottom:10px}
.add-class{display:flex;gap:6px;margin-bottom:8px}
.add-class input{flex:1;min-width:0}
.cls-mgr{display:flex;flex-direction:column;gap:5px}
.cls-mgr-row{display:flex;align-items:center;gap:6px}
.cls-idx{min-width:16px;font-size:12px;color:var(--muted);text-align:center}
.cls-name-inp{flex:1;min-width:0}

/* right annotation panel */
.rpanel{grid-column:3;border-left:1px solid var(--border);background:var(--panel);padding:12px;overflow-y:auto;display:flex;flex-direction:column;gap:14px;min-height:0}
.rp-sec{display:flex;flex-direction:column}
.rp-note{flex:1;min-height:0}
.cls-picker{display:flex;flex-direction:column;gap:4px}
.cls-row{display:flex;align-items:center;gap:8px;padding:5px 7px;border:1px solid var(--border);border-radius:7px;cursor:pointer}
.cls-row:hover{background:var(--bg)}
.cls-row.active{border-color:var(--accent);background:var(--accent-bg)}
.cls-color{width:26px;height:22px;padding:0;border:1px solid var(--border);border-radius:5px;cursor:pointer;background:none;flex:none}
.cls-name{font-size:13px;color:var(--ink)}
.cls-row.active .cls-name{color:var(--accent);font-weight:500}
.cls-key{margin-left:auto;min-width:18px;height:18px;padding:0 4px;border:1px solid var(--border);border-radius:4px;font-size:11px;color:var(--muted);display:inline-flex;align-items:center;justify-content:center;font-variant-numeric:tabular-nums;background:var(--bg)}
.cls-row.active .cls-key{border-color:var(--accent);color:var(--accent)}
.note-area{flex:1;min-height:130px;width:100%;resize:vertical;border:1px solid var(--border);border-radius:8px;padding:8px;font:inherit;font-size:13px;color:var(--ink);background:var(--panel)}
.note-area:focus{outline:none;border-color:var(--accent)}
/* note markers (numbered circles placed from the note panel) */
.marker-row{display:flex;align-items:center;gap:8px;flex-wrap:wrap;margin-top:8px}
.marker-chips{display:flex;gap:4px;flex-wrap:wrap}
.mk-chip{display:inline-flex;align-items:center;gap:4px;border:1px solid var(--border);border-radius:999px;padding:2px 7px 2px 3px;font-size:12px}
.mk-chip:hover{border-color:#7c3aed}
.mk-dot{width:17px;height:17px;border-radius:50%;background:#7c3aed;color:#fff;display:inline-flex;align-items:center;justify-content:center;font-size:11px}
.mk-x{cursor:pointer;color:var(--muted);padding:0 2px}
.mk-x:hover{color:var(--warn)}
body.marker-arming #btnAddMarker{background:var(--accent-bg);border-color:var(--accent);color:var(--accent)}
body.marker-arming #view{cursor:crosshair}
.tool-switch{display:flex;gap:6px;margin-bottom:8px}
.btn.active{background:var(--accent-bg);border-color:var(--accent);color:var(--accent);font-weight:500}
.brush-opts{display:none}
body.brush-mode .brush-opts{display:block}
.click-opts{display:block}
body.brush-mode .click-opts{display:none}
.selbrush-opts{display:none;margin-top:8px}
body.sel-brush-mode .selbrush-opts{display:block}
.single-opts{display:block;margin-top:8px}
body.sel-brush-mode .single-opts{display:none}
#geomPanel.hidden,#geomMetricRow.hidden{display:none}
#layerSec.hidden{display:none}
.layer-bar{display:flex;flex-wrap:wrap;gap:6px}
.layer-chip{display:flex;align-items:center;gap:3px;padding:4px 5px 4px 9px;border:1px solid var(--border);border-radius:7px;background:var(--panel);cursor:pointer;font-size:12px;color:var(--muted)}
.layer-chip.active{border-color:var(--accent);background:var(--accent-bg);color:var(--accent);font-weight:500}
.layer-chip .lname{overflow:hidden;text-overflow:ellipsis;white-space:nowrap;max-width:130px}
.layer-chip .lx,.layer-chip .led{padding:0 3px;border-radius:4px;font-size:11px;opacity:.65}
.layer-chip .lx:hover,.layer-chip .led:hover{opacity:1;background:var(--bg)}
.geom-stats{line-height:1.6;margin-bottom:6px}
.geom-hist{display:flex;align-items:flex-end;gap:2px;height:34px;margin:2px 0 8px;padding:3px;border:1px solid var(--border);border-radius:6px}
.geom-hist i{flex:1;background:var(--accent);min-height:1px;border-radius:1px;opacity:.85}
.modal-overlay{position:fixed;inset:0;background:rgba(0,0,0,.45);display:flex;align-items:center;justify-content:center;z-index:100}
.modal-overlay.hidden{display:none}
.modal{background:var(--panel);border-radius:12px;padding:26px 30px;max-width:440px;box-shadow:0 12px 44px rgba(0,0,0,.28);text-align:center}
.modal-warn{color:#dc2626;font-size:17px;font-weight:700;margin:0 0 22px;line-height:1.7}
.modal-actions{display:flex;align-items:center;justify-content:center;gap:20px}
.btn-danger{font-size:12px;padding:6px 12px;color:var(--warn);border-color:var(--border)}
.btn-danger:hover:not(:disabled){border-color:var(--warn)}
.btn-cancel{font-size:18px;font-weight:700;padding:13px 34px;border-radius:10px;border-color:var(--accent);background:var(--accent);color:#fff}
.btn-cancel:hover:not(:disabled){filter:brightness(1.06);border-color:var(--accent)}
/* data-format reference modal */
.doc-modal{width:min(780px,92vw);max-width:min(780px,92vw);max-height:86vh;display:flex;flex-direction:column;text-align:left;padding:18px 22px}
.doc-head{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-bottom:8px}
.doc-title{margin:0;font-size:16px}
.doc-body{overflow-y:auto;min-height:0;font-size:13px;line-height:1.6}
.doc-p{margin:6px 0}
.doc-tree{background:var(--bg);border:1px solid var(--border);border-radius:8px;padding:10px 12px;overflow-x:auto;font:12px/1.55 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;white-space:pre;margin:8px 0}
.doc-sec{margin-top:12px}
.doc-sec h4{margin:0 0 4px;font-size:13px}
.doc-sec ul{margin:4px 0;padding-left:20px}
.doc-sec li{margin:3px 0}
.doc-body code{background:var(--bg);border:1px solid var(--border);border-radius:4px;padding:0 4px;font-size:12px}
.doc-tabs{display:flex;gap:6px}
.doc-body.hidden,.doc-prompt.hidden{display:none}
.doc-prompt{flex:1 1 auto;min-height:0;display:flex;flex-direction:column;gap:8px;overflow:hidden}
.doc-prompt .btn{align-self:flex-start}
.doc-prompt-wrap{flex:1;min-height:0;overflow:auto;border:1px solid var(--border);border-radius:8px;background:var(--bg)}
.doc-prompt-text{margin:0;padding:12px;white-space:pre-wrap;word-break:break-word;font:12px/1.55 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;color:var(--ink)}
.loupe-panel{position:fixed;top:40px;right:0;width:320px;max-height:calc(100vh - 40px);overflow:auto;background:var(--panel);border-left:1px solid var(--border);box-shadow:-8px 0 24px rgba(0,0,0,.18);z-index:90;padding:10px 12px;pointer-events:none}
.loupe-panel.hidden{display:none}
.loupe-head{display:flex;align-items:center;justify-content:space-between;gap:8px;margin-bottom:2px}
.loupe-coord{font-weight:600;font-variant-numeric:tabular-nums}
.loupe-meanctl input{accent-color:var(--accent)}
.loupe-sub{font-size:11px;margin:6px 0 4px}
.loupe-strip{display:flex;flex-wrap:wrap;gap:5px}
.loupe-tile{display:flex;flex-direction:column;align-items:center;gap:2px}
.loupe-tile canvas{width:92px;height:92px;display:block;border:1px solid var(--border);border-radius:4px;background:#2b2f36}
.loupe-tile.cur canvas{border:2px solid var(--accent)}
.loupe-tile .cap{font-size:10px;color:var(--muted);line-height:1.1;text-align:center}
.loupe-tile.cur .cap{color:var(--accent);font-weight:600}
.loupe-curve{width:100%;height:120px;display:block}