:root{
  --bg:#f4f6f8;--panel:#fff;--line:#dfe5ea;--text:#263238;--muted:#78909c;--accent:#1565c0;--danger:#d32f2f;
  --top:52px;--pal:250px;--props:270px;--status:26px;
}
*{box-sizing:border-box}
html,body{margin:0;height:100%;font:14px/1.4 system-ui,Segoe UI,Roboto,Arial,sans-serif;color:var(--text);background:var(--bg)}
button{font:inherit;color:inherit;cursor:pointer}
.hidden{display:none!important}
.grow{flex:1}

/* ---------- start ---------- */
.start{min-height:100%;display:flex;align-items:center;justify-content:center;padding:40px 20px;background:
  radial-gradient(1200px 600px at 10% -10%,#e3f2fd 0,transparent 60%),radial-gradient(900px 500px at 110% 110%,#ffebee 0,transparent 60%),var(--bg)}
.start-inner{max-width:980px;width:100%}
.brand{display:flex;gap:16px;align-items:center;margin-bottom:40px}
.brand h1{margin:0;font-size:34px;letter-spacing:.5px}
.brand p{margin:2px 0 0;color:var(--muted)}
.start h2{font-weight:500;color:var(--muted);margin:0 0 14px}
.modules{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:16px}
.module-card{background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:22px 18px;text-align:left;display:flex;flex-direction:column;gap:8px;transition:.15s;box-shadow:0 1px 2px rgba(0,0,0,.04)}
.module-card:hover{transform:translateY(-3px);box-shadow:0 10px 24px rgba(0,0,0,.09);border-color:var(--c)}
.module-card svg{width:56px;height:56px;color:var(--text)}
.module-card strong{font-size:18px}
.module-card span{color:var(--muted);font-size:13px}
.recent{margin-top:36px}
.recent h3{font-weight:500;color:var(--muted);margin:0 0 10px;font-size:14px}
.recent-list{display:flex;flex-wrap:wrap;gap:8px}
.recent-list button{background:var(--panel);border:1px solid var(--line);border-radius:8px;padding:8px 12px;display:flex;gap:8px;align-items:center}
.recent-list button i{width:10px;height:10px;border-radius:50%;display:inline-block}

/* ---------- editor layout ---------- */
.editor{height:100vh;display:grid;grid-template-columns:var(--pal) 1fr var(--props);grid-template-rows:var(--top) 1fr var(--status);
  grid-template-areas:"top top top" "pal canvas props" "status status status"}
.topbar{grid-area:top;display:flex;align-items:center;gap:6px;padding:0 10px;background:var(--panel);border-bottom:1px solid var(--line);overflow:visible;z-index:5}
.brand-sm{font-weight:600;font-size:16px;white-space:nowrap}
.brand-sm span{font-weight:400;color:var(--muted);font-size:13px}
.sep{width:1px;height:28px;background:var(--line);margin:0 4px}
.tools{display:flex;gap:2px;align-items:center}
.icon-btn,.tool{width:34px;height:34px;border:0;background:transparent;border-radius:8px;display:inline-flex;align-items:center;justify-content:center;font-size:18px;color:var(--text)}
.icon-btn svg,.tool svg{width:20px;height:20px;fill:currentColor}
.icon-btn:hover,.tool:hover{background:#eceff1}
.tool.active,.toggle.active{background:#e3f2fd;color:var(--accent)}
.icon-btn.danger:hover{background:#ffebee;color:var(--danger)}
.zoom{font-size:12px;color:var(--muted);min-width:42px;text-align:center}
.btn{height:32px;padding:0 12px;border:1px solid var(--line);background:var(--panel);border-radius:8px}
.btn:hover{background:#f1f4f6}
.btn.primary{background:var(--accent);color:#fff;border-color:var(--accent)}
.btn.primary:hover{background:#0d47a1}
.btn.primary.ok{background:#2e7d32;border-color:#2e7d32}
.btn.primary.err{background:var(--danger);border-color:var(--danger)}
.btn.primary:disabled{opacity:.7;cursor:default}
.hint.ok{background:#2e7d32}.hint.err{background:var(--danger)}
.title-input{height:32px;border:1px solid transparent;border-radius:8px;padding:0 10px;font-weight:600;min-width:160px;background:transparent}
.title-input:hover,.title-input:focus{border-color:var(--line);background:var(--panel);outline:0}
.dropdown{position:relative}
.dropdown .menu{display:none;position:absolute;right:0;top:36px;background:var(--panel);border:1px solid var(--line);border-radius:8px;box-shadow:0 8px 24px rgba(0,0,0,.12);min-width:200px;padding:4px;z-index:20}
.dropdown.open .menu{display:block}
.menu button{display:block;width:100%;text-align:left;border:0;background:transparent;padding:8px 10px;border-radius:6px}
.menu button:hover{background:#eceff1}
.menu button.cur{background:#e3f2fd}

/* line types */
.linetypes{display:flex;gap:4px;align-items:center}
.lt{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--line);border-radius:999px;padding:3px 9px 3px 5px;font-size:12px;white-space:nowrap;background:var(--panel)}
.lt i{width:22px;height:0;border-top:3px solid var(--c);display:inline-block}
.lt.dashed i{border-top-style:dashed}
.lt.active{border-color:var(--c);background:color-mix(in srgb,var(--c) 12%,#fff);font-weight:600}
.lt-dd .menu{left:0;right:auto;min-width:220px}
.lt-dd .menu .lt,.lt-btn .lt{border:0;padding:0;background:transparent;font-size:13px}
.lt-btn{display:inline-flex;align-items:center;gap:6px;min-width:150px;justify-content:space-between}
.lt-btn .lt{font-weight:600}

/* palette */
.palette{grid-area:pal;background:var(--panel);border-right:1px solid var(--line);overflow-y:auto;padding:8px}
.search{width:100%;height:32px;border:1px solid var(--line);border-radius:8px;padding:0 10px;margin-bottom:8px}
.pal-group h4{margin:10px 4px 6px;font-size:12px;text-transform:uppercase;letter-spacing:.5px;color:var(--muted);cursor:pointer;display:flex;align-items:center;gap:6px}
.pal-group h4::before{content:"▾";font-size:10px}
.pal-group.collapsed h4::before{content:"▸"}
.pal-group.collapsed .pal-items{display:none}
.pal-items{display:grid;grid-template-columns:repeat(3,1fr);gap:4px}
.pal-item{border:1px solid transparent;border-radius:8px;padding:6px 2px 4px;display:flex;flex-direction:column;align-items:center;gap:3px;background:transparent;cursor:grab}
.pal-item:hover{border-color:var(--line);background:#f7f9fa}
.pal-item.active{border-color:var(--accent);background:#e3f2fd}
.pal-item svg{width:44px;height:44px}
.pal-item span{font-size:10.5px;line-height:1.15;text-align:center;color:#455a64;height:24px;overflow:hidden}
.pal-module{margin-top:8px;border-top:2px solid var(--line);padding-top:6px}
.pal-module>h3{font-size:13px;margin:4px;display:flex;align-items:center;gap:6px;cursor:pointer}
.pal-module>h3 i{width:10px;height:10px;border-radius:3px;display:inline-block}
.pal-module.collapsed .pal-group{display:none}

/* canvas */
.canvas-wrap{grid-area:canvas;position:relative;overflow:hidden;background:#fff}
#svg{width:100%;height:100%;display:block;touch-action:none;user-select:none}
#svg.tool-line{cursor:crosshair}
#svg.tool-text{cursor:text}
#svg.tool-pan{cursor:grab}
#svg.panning{cursor:grabbing}
.hint{position:absolute;left:12px;bottom:12px;background:rgba(38,50,56,.85);color:#fff;font-size:12px;padding:6px 10px;border-radius:6px;pointer-events:none;opacity:0;transition:.2s}
.hint.show{opacity:1}

.node{cursor:move}
.node text{font-family:system-ui,Segoe UI,Arial,sans-serif}
.node .sym *{vector-effect:non-scaling-stroke}
.node.selected .selbox{stroke:var(--accent);stroke-width:1.5;stroke-dasharray:4 3;fill:rgba(21,101,192,.06)}
.port{fill:#fff;stroke:#90a4ae;stroke-width:1.5;cursor:crosshair;opacity:0;transition:opacity .12s}
.node:hover .port,#svg.tool-line .port,#svg.drawing .port,.node.selected .port{opacity:1}
.port:hover,.port.hot{fill:#ffeb3b;stroke:#f57f17;r:6}
.port.t-h{stroke:#1565c0}.port.t-e{stroke:#5d4037}.port.t-a{stroke:#2e7d32}
.port.lt-vl{stroke:#d32f2f}.port.lt-rl{stroke:#1565c0}.port.lt-ptv{stroke:#e65100}.port.lt-hv{stroke:#0288d1}.port.lt-cirk{stroke:#f9a825}.port.lt-plin{stroke:#f9a825;fill:#fff59d}.port.lt-kond{stroke:#00838f}.port.lt-sig{stroke:#7b1fa2}.port.lt-reg{stroke:#616161}.port.lt-el{stroke:#212121;fill:#eee}.port.lt-dim{stroke:#78909c;fill:#cfd8dc}
.port.lt-bus{stroke:#8e24aa;fill:#f3e5f5}.port.lt-tv{stroke:#d32f2f}.port.lt-kis{stroke:#2e7d32}.port.lt-odvod{stroke:#6d4c41;fill:#efebe9}.port.lt-obor{stroke:#8d6e63;fill:#f5f5f5}
.port.lt-dov{stroke:#1976d2;fill:#e3f2fd}.port.lt-ods{stroke:#e53935;fill:#ffebee}.port.lt-vanj{stroke:#43a047;fill:#e8f5e9}.port.lt-istr{stroke:#8d6e63;fill:#efebe9}.port.lt-opt{stroke:#fb8c00;fill:#fff3e0}
.port.lt-kab{stroke:#212121;fill:#eee}.port.lt-l1{stroke:#5d4037}.port.lt-l2{stroke:#212121}.port.lt-l3{stroke:#9e9e9e}.port.lt-n{stroke:#1e88e5}.port.lt-pe{stroke:#43a047;fill:#e8f5e9}.port.lt-upr{stroke:#fb8c00;fill:#fff3e0}.port.lt-slab{stroke:#00897b;fill:#e0f2f1}.port.lt-dc{stroke:#e53935;fill:#ffebee}
.line-hit{stroke:transparent;stroke-width:14;fill:none;cursor:pointer}
.line.selected .line-vis{filter:drop-shadow(0 0 3px rgba(21,101,192,.9))}
.vtx{fill:#fff;stroke:var(--accent);stroke-width:1.5;cursor:move}
.vtx.mid{fill:var(--accent);opacity:.6;r:3.5}
.marquee{fill:rgba(21,101,192,.08);stroke:var(--accent);stroke-dasharray:4 3}
.txt{cursor:move;font-family:system-ui,Segoe UI,Arial,sans-serif}
.txt.selected rect{stroke:var(--accent);stroke-dasharray:4 3;fill:rgba(21,101,192,.06)}
.linelabel{font:11px system-ui,Segoe UI,Arial,sans-serif;paint-order:stroke;stroke:#fff;stroke-width:3px;fill:#37474f}
.nodelabel{font-size:11px;fill:#37474f;paint-order:stroke;stroke:#fff;stroke-width:3px}
.nodetag{font-size:11px;font-weight:700;fill:#263238;paint-order:stroke;stroke:#fff;stroke-width:3px}

/* props */
.props{grid-area:props;background:var(--panel);border-left:1px solid var(--line);overflow-y:auto;padding:12px}
.props-empty{color:var(--muted);font-size:13px;padding:8px}
.props h3{margin:0 0 10px;font-size:14px}
.props label{display:block;font-size:12px;color:var(--muted);margin:10px 0 4px}
.props input,.props select,.props textarea{width:100%;height:32px;border:1px solid var(--line);border-radius:8px;padding:0 8px;font:inherit}
.props textarea{height:70px;padding:6px 8px}
.props .row{display:flex;gap:8px}
.props .row>*{flex:1}
.props .chips{display:flex;flex-wrap:wrap;gap:4px}
.props .chips .lt{cursor:pointer}
.props .small{font-size:12px;color:var(--muted);margin-top:14px;line-height:1.5}
.props kbd{background:#eceff1;border-radius:4px;padding:0 5px;font-family:inherit;font-size:11px}

.statusbar{grid-area:status;display:flex;align-items:center;padding:0 12px;font-size:12px;color:var(--muted);background:var(--panel);border-top:1px solid var(--line)}

/* modal */
.modal{position:fixed;inset:0;background:rgba(0,0,0,.35);display:flex;align-items:center;justify-content:center;z-index:50}
.modal-box{background:var(--panel);border-radius:12px;padding:18px;min-width:440px;max-width:90vw;max-height:80vh;display:flex;flex-direction:column}
.modal-box h3{margin:0 0 12px}
.modal .list{overflow-y:auto;flex:1;border:1px solid var(--line);border-radius:8px}
.modal .list .item{display:flex;align-items:center;gap:10px;padding:10px 12px;border-bottom:1px solid var(--line)}
.modal .list .item:hover{background:#f7f9fa}
.modal .list .item i{width:10px;height:10px;border-radius:50%}
.modal .list .item b{flex:1;cursor:pointer}
.modal .list .item small{color:var(--muted)}
.modal .list .item .x{border:0;background:transparent;color:var(--muted);font-size:16px}
.modal .list .item .x:hover{color:var(--danger)}
.modal-actions{display:flex;justify-content:flex-end;margin-top:12px}

/* auth */
.auth-box{min-width:380px;max-width:420px}
.tabs{display:flex;border-bottom:1px solid var(--line);margin-bottom:10px}
.tab{flex:1;border:0;background:transparent;padding:10px;font-weight:600;color:var(--muted);border-bottom:2px solid transparent;margin-bottom:-1px}
.tab.active{color:var(--accent);border-bottom-color:var(--accent)}
.auth-msg{margin:0 0 6px;color:var(--muted);font-size:13px;min-height:18px}
.auth-box label{display:block;font-size:12px;color:var(--muted);margin:10px 0 4px}
.auth-box input{width:100%;height:36px;border:1px solid var(--line);border-radius:8px;padding:0 10px;font:inherit}
.auth-box .row{display:flex;gap:10px}.auth-box .row>*{flex:1}
.auth-err{color:var(--danger);font-size:13px;min-height:18px;margin-top:8px}
.btn.wide{width:100%;height:38px;margin-top:4px}
.auth-box label.check{display:flex;align-items:center;gap:8px;font-size:14px;color:var(--text);margin:6px 0 10px}
.auth-box label.check input{width:auto;height:auto}
#shareLinkRow.hidden{display:none}
.shared-badge{font-size:12px;color:var(--muted);background:#fff8e1;border:1px solid #ffe082;border-radius:6px;padding:3px 8px;white-space:nowrap}
.start-user{position:fixed;top:14px;right:18px;display:flex;gap:8px;align-items:center;font-size:13px;color:var(--muted)}
.start-user .btn{height:30px}
a.btn{display:inline-flex;align-items:center;text-decoration:none;color:inherit}
.start-footer{position:fixed;left:0;right:0;bottom:10px;text-align:center;font-size:12px;color:var(--muted);pointer-events:none}
.statusbar .copy{margin-left:18px;padding-left:14px;border-left:1px solid var(--line);color:var(--muted);white-space:nowrap}
.user .btn{max-width:180px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}

@media print{
  .topbar,.palette,.props,.statusbar,.hint{display:none!important}
  .editor{display:block;height:auto}
  .canvas-wrap{position:static;height:100vh}
  #gridRect{display:none}
}
@media (max-width:900px){
  :root{--pal:200px;--props:220px}
  .linetypes{max-width:300px}
}