:root {
    --bg: #0a0c10;
    --surface: #111318;
    --surface2: #181b22;
    --surface3: #1e222c;
    --border: #2a2f3d;
    --border2: #343a4d;
    --text: #e8eaf0;
    --text2: #8892a4;
    --text3: #4a5568;
    --accent: #4f8ef7;
    --accent2: #2d5fcf;
    --green: #34d399;
    --green-dim: #1a3d30;
    --red: #f87171;
    --red-dim: #3d1a1a;
    --yellow: #fbbf24;
    --yellow-dim: #3d2e0a;
    --purple: #a78bfa;
    --purple-dim: #2a1f4a;
    --orange: #fb923c;
    --orange-dim: #3d200a;

    --node-root: #ef4444;
    --node-root-bg: #2a0f0f;
    --node-inter: #f59e0b;
    --node-inter-bg: #2a1e0a;
    --node-leaf: #34d399;
    --node-leaf-bg: #0a2a1e;
    --node-cross: #a78bfa;
    --node-cross-bg: #1e0a3a;
  }

  * { box-sizing: border-box; margin: 0; padding: 0; }
  body {
    background: var(--bg);
    color: var(--text);
    font-family: 'Syne', sans-serif;
    height: 100vh;
    overflow: hidden;
    display: flex;
    flex-direction: column;
  }

  /* ── Header ── */
  header {
    height: 52px;
    display: flex;
    align-items: center;
    padding: 0 20px;
    border-bottom: 1px solid var(--border);
    background: var(--surface);
    gap: 20px;
    flex-shrink: 0;
    z-index: 100;
  }
  .logo {
    font-size: 18px;
    font-weight: 800;
    letter-spacing: -0.5px;
    color: var(--text);
    display: flex;
    align-items: center;
    gap: 8px;
  }
  .logo-icon {
    width: 26px; height: 26px;
    background: linear-gradient(135deg, var(--accent), var(--purple));
    border-radius: 6px;
    display: flex; align-items: center; justify-content: center;
    font-size: 14px;
  }

  .version-badge {
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 3px 9px;
    border-radius: 20px;
    border: 1px solid var(--border2);
    background: var(--surface2);
    color: var(--text3);
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    font-weight: 600;
    cursor: pointer;
    transition: all .15s;
    user-select: none;
  }
  .version-badge:hover {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(79,142,247,.08);
  }
  .version-dot {
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--red);
    flex-shrink: 0;
    animation: pulse 2s infinite;
    display: none;
  }
  .version-dot.show { display: block; }

  /* Changelog modal */
  .changelog-modal {
    background: var(--surface);
    border: 1px solid var(--border2);
    border-radius: 14px;
    width: 500px;
    max-height: 75vh;
    overflow-y: auto;
    padding: 24px;
    box-shadow: 0 24px 60px rgba(0,0,0,.5);
  }

  /* ── CSR Modal ── */
  .csr-modal {
    background: var(--surface);
    border: 1px solid var(--border2);
    border-radius: 14px;
    width: 680px;
    max-width: 95vw;
    max-height: 88vh;
    padding: 0;
    box-shadow: 0 24px 60px rgba(0,0,0,.5);
    display: flex;
    flex-direction: column;
    overflow: hidden;
  }
  .csr-modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 24px 0;
    flex-shrink: 0;
  }
  .csr-modal-header h2 { font-family:'Syne',sans-serif; font-size:16px; font-weight:700; margin:0; }
  .csr-modal-close {
    background:none; border:1px solid var(--border); border-radius:6px;
    color:var(--text2); width:28px; height:28px; cursor:pointer; font-size:12px;
    display:flex; align-items:center; justify-content:center; flex-shrink:0;
  }
  .csr-modal-close:hover { background:var(--red-dim); border-color:var(--red); color:var(--red); }
  .csr-tabs {
    display: flex;
    gap: 4px;
    padding: 16px 24px 0;
    border-bottom: 1px solid var(--border);
    flex-shrink: 0;
  }
  .csr-tab-btn {
    background: none; border: none; border-bottom: 2px solid transparent;
    color: var(--text2); font-size: 13px; font-family: 'Syne', sans-serif;
    font-weight: 600; padding: 6px 16px 10px; cursor: pointer;
    margin-bottom: -1px;
  }
  .csr-tab-btn.active { color: var(--accent); border-bottom-color: var(--accent); }
  .csr-tab-btn:hover:not(.active) { color: var(--text); }
  .csr-body {
    padding: 20px 24px;
    overflow-y: auto;
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 14px;
  }
  .csr-field { display: flex; flex-direction: column; gap: 6px; }
  .csr-label {
    font-size: 11px; font-weight: 600; color: var(--text2);
    text-transform: uppercase; letter-spacing: .06em;
  }
  .csr-label span { color: var(--red); margin-left: 2px; }
  .csr-input {
    background: var(--surface2); border: 1px solid var(--border2);
    border-radius: 7px; color: var(--text);
    font-family: 'JetBrains Mono', monospace; font-size: 12px;
    padding: 8px 12px; width: 100%; box-sizing: border-box;
  }
  .csr-input:focus { outline: none; border-color: var(--accent); }
  .csr-select {
    background: var(--surface2); border: 1px solid var(--border2);
    border-radius: 7px; color: var(--text); font-size: 12px;
    padding: 8px 12px; width: 100%; cursor: pointer;
  }
  .csr-san-list { display: flex; flex-direction: column; gap: 6px; }
  .csr-san-row { display: flex; gap: 6px; align-items: center; }
  .csr-san-type {
    background: var(--surface2); border: 1px solid var(--border2);
    border-radius: 7px; color: var(--text); font-size: 11px;
    padding: 8px 8px; cursor: pointer; width: 70px; flex-shrink: 0;
  }
  .csr-san-input { flex: 1; }
  .csr-san-del {
    background: none; border: 1px solid var(--border); border-radius: 5px;
    color: var(--text3); font-size: 11px; padding: 4px 8px; cursor: pointer; flex-shrink: 0;
  }
  .csr-san-del:hover { border-color: var(--red); color: var(--red); }
  .csr-add-san {
    background: none; border: 1px dashed var(--border2); border-radius: 7px;
    color: var(--text3); font-size: 11px; padding: 6px; cursor: pointer; width: 100%;
  }
  .csr-add-san:hover { border-color: var(--accent); color: var(--accent); }
  .csr-divider { border: none; border-top: 1px solid var(--border); margin: 4px 0; }
  .csr-output-block {
    background: var(--surface2); border: 1px solid var(--border2);
    border-radius: 8px; padding: 12px; position: relative;
  }
  .csr-output-label {
    font-size: 10px; font-weight: 600; color: var(--text2);
    text-transform: uppercase; letter-spacing: .06em;
    display: flex; align-items: center; justify-content: space-between;
    margin-bottom: 8px;
  }
  .csr-output-actions { display: flex; gap: 6px; }
  .csr-copy-btn {
    background: var(--surface3); border: 1px solid var(--border2);
    border-radius: 4px; color: var(--text2); font-size: 10px;
    padding: 2px 8px; cursor: pointer; font-family: 'JetBrains Mono', monospace;
  }
  .csr-copy-btn:hover { color: var(--text); border-color: var(--text2); }
  .csr-copy-btn.copied { color: var(--green); border-color: var(--green); }
  .csr-pem {
    font-family: 'JetBrains Mono', monospace; font-size: 10px;
    color: var(--green); word-break: break-all; white-space: pre-wrap;
    max-height: 100px; overflow-y: auto; line-height: 1.5;
  }
  .csr-key-pem { color: var(--yellow); }
  .csr-parse-result {
    background: var(--surface2); border: 1px solid var(--border2);
    border-radius: 8px; padding: 16px;
  }
  .csr-parse-row {
    display: flex; gap: 12px; padding: 6px 0;
    border-bottom: 1px solid var(--border); font-size: 12px;
  }
  .csr-parse-row:last-child { border-bottom: none; }
  .csr-parse-key { color: var(--text2); width: 130px; flex-shrink: 0; }
  .csr-parse-val { color: var(--text); font-family: 'JetBrains Mono', monospace; word-break: break-all; }
  .csr-parse-val.ok { color: var(--green); }
  .csr-ext-section { display: flex; flex-direction: column; gap: 6px; }
  .csr-ext-label { font-size: 11px; color: var(--text2); text-transform: uppercase; letter-spacing: .05em; font-weight: 600; }
  .csr-checkbox-grid { display: flex; flex-wrap: wrap; gap: 6px 16px; }
  .csr-checkbox-item { display: flex; align-items: center; gap: 5px; font-size: 12px; color: var(--text); cursor: pointer; user-select: none; }
  .csr-checkbox-item input[type=checkbox] { accent-color: var(--accent); width: 13px; height: 13px; cursor: pointer; }
  .csr-san-tag {
    display: inline-block; font-size: 9px; padding: 1px 5px;
    border-radius: 3px; margin-right: 4px;
    background: var(--purple-dim); color: var(--purple); border: 1px solid var(--purple);
  }
  .csr-san-tag.ip { background: var(--yellow-dim); color: var(--yellow); border-color: var(--yellow); }

  /* ── Node Key Upload ── */
  .node-key-row {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 5px 10px;
    border-top: 1px solid var(--border);
    font-size: 11px;
  }
  .node-key-status { color: var(--green); flex: 1; }
  .node-key-missing { color: var(--text3); flex: 1; }
  .node-key-btn {
    background: none;
    border: 1px solid var(--border2);
    border-radius: 4px;
    color: var(--text2);
    font-size: 10px;
    padding: 2px 7px;
    cursor: pointer;
    font-family: 'JetBrains Mono', monospace;
  }
  .node-key-btn:hover { border-color: var(--green); color: var(--green); }
  .node-signer-badge {
    font-size: 9px;
    padding: 1px 6px;
    border-radius: 3px;
    background: var(--green-dim);
    color: var(--green);
    border: 1px solid var(--green);
    font-weight: 600;
    margin-left: auto;
  }

  /* ── Key Upload Modal ── */
  .key-upload-modal {
    background: var(--surface);
    border: 1px solid var(--border2);
    border-radius: 14px;
    width: 480px;
    padding: 24px;
    box-shadow: 0 24px 60px rgba(0,0,0,.5);
  }
  .key-upload-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 16px;
  }
  .key-upload-header h2 { font-family:'Syne',sans-serif; font-size:16px; font-weight:700; margin:0; }
  .key-upload-close {
    background:none; border:1px solid var(--border); border-radius:6px;
    color:var(--text2); width:28px; height:28px; cursor:pointer; font-size:12px;
    display:flex; align-items:center; justify-content:center;
  }
  .key-upload-close:hover { background:var(--red-dim); border-color:var(--red); color:var(--red); }
  .key-textarea {
    width: 100%; box-sizing: border-box;
    background: var(--surface2); border: 1px solid var(--border2);
    border-radius: 8px; color: var(--text);
    font-family: 'JetBrains Mono', monospace; font-size: 11px;
    padding: 10px; resize: vertical; height: 140px; margin-bottom: 12px;
  }
  .key-textarea:focus { outline: none; border-color: var(--green); }
  .key-upload-hint { font-size: 11px; color: var(--text3); margin-bottom: 12px; }

  /* ── Generate Modal — skip/generate state ── */
  .gen-node-skip { opacity: 0.5; }
  .gen-skip-label {
    font-size: 10px; padding: 2px 7px; border-radius: 3px;
    background: var(--surface3); color: var(--text2);
    border: 1px solid var(--border); white-space: nowrap;
  }
  .gen-skip-label.ready { background: var(--green-dim); color: var(--green); border-color: var(--green); }
  .gen-skip-label.warn  { background: var(--yellow-dim); color: var(--yellow); border-color: var(--yellow); }
  .gen-key-inline {
    display: flex; align-items: center; gap: 6px;
    margin-top: 4px; padding: 4px 0;
  }
  .gen-key-inline-label { font-size: 10px; color: var(--text3); }

  /* ── Keyboard Shortcuts Modal ── */
  .shortcuts-modal {
    background: var(--surface);
    border: 1px solid var(--border2);
    border-radius: 14px;
    width: 420px;
    padding: 24px;
    box-shadow: 0 24px 60px rgba(0,0,0,.5);
  }
  .shortcuts-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 20px;
  }
  .shortcuts-header h2 {
    font-family: 'Syne', sans-serif;
    font-size: 16px;
    font-weight: 700;
    color: var(--text);
    margin: 0;
  }
  .shortcuts-close {
    background: none;
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--text2);
    width: 28px;
    height: 28px;
    cursor: pointer;
    font-size: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
  }
  .shortcuts-close:hover { background: var(--red-dim); border-color: var(--red); color: var(--red); }
  .shortcuts-group { margin-bottom: 16px; }
  .shortcuts-group-label {
    font-size: 10px;
    font-weight: 600;
    color: var(--text3);
    text-transform: uppercase;
    letter-spacing: .08em;
    margin-bottom: 8px;
  }
  .shortcut-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 6px 0;
    border-bottom: 1px solid var(--border);
  }
  .shortcut-row:last-child { border-bottom: none; }
  .shortcut-desc { font-size: 12px; color: var(--text2); }
  .shortcut-keys { display: flex; gap: 4px; }
  kbd {
    background: var(--surface3);
    border: 1px solid var(--border2);
    border-radius: 4px;
    color: var(--text);
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px;
    padding: 2px 6px;
    white-space: nowrap;
  }
  .changelog-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    margin-bottom: 20px;
    gap: 12px;
  }
  .changelog-header h2 {
    font-size: 18px;
    font-weight: 800;
    color: var(--text);
  }
  .changelog-header p {
    font-size: 12px;
    color: var(--text3);
    margin-top: 3px;
    font-family: 'JetBrains Mono', monospace;
  }
  .changelog-close {
    width: 28px; height: 28px;
    border-radius: 6px;
    border: 1px solid var(--border);
    background: none;
    color: var(--text3);
    cursor: pointer;
    font-size: 14px;
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0;
    transition: all .15s;
  }
  .changelog-close:hover { background: var(--red-dim); border-color: var(--red); color: var(--red); }

  .changelog-entry {
    margin-bottom: 20px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border);
  }
  .changelog-entry:last-child { border-bottom: none; margin-bottom: 0; padding-bottom: 0; }
  .changelog-ver-row {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 10px;
  }
  .changelog-ver {
    font-family: 'JetBrains Mono', monospace;
    font-size: 14px;
    font-weight: 700;
    color: var(--text);
  }
  .changelog-ver.latest { color: var(--accent); }
  .changelog-tag-latest {
    font-size: 9px;
    font-weight: 700;
    letter-spacing: 1px;
    text-transform: uppercase;
    padding: 2px 7px;
    border-radius: 4px;
    background: rgba(79,142,247,.15);
    color: var(--accent);
    border: 1px solid var(--accent2);
  }
  .changelog-date {
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px;
    color: var(--text3);
    margin-left: auto;
  }
  .changelog-items {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 5px;
  }
  .changelog-items li {
    font-size: 12px;
    color: var(--text2);
    font-family: 'JetBrains Mono', monospace;
    line-height: 1.5;
    display: flex;
    gap: 8px;
  }
  .changelog-items li::before { content: '—'; color: var(--text3); flex-shrink: 0; }
  .changelog-items li .tag { font-size: 9px; padding: 1px 6px; flex-shrink: 0; align-self: center; }
  .header-tabs {
    display: flex;
    gap: 4px;
    margin-left: 20px;
  }
  .tab-btn {
    padding: 5px 14px;
    border-radius: 6px;
    border: 1px solid transparent;
    background: none;
    color: var(--text2);
    font-family: 'Syne', sans-serif;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    transition: all .15s;
  }
  .tab-btn.active {
    background: var(--surface3);
    border-color: var(--border2);
    color: var(--text);
  }
  .tab-btn:hover:not(.active) { color: var(--text); }
  .header-actions {
    margin-left: auto;
    display: flex;
    gap: 8px;
    align-items: center;
  }

  .contact-btn {
    position: relative;
    width: 32px; height: 32px;
    border-radius: 7px;
    border: 1px solid var(--border2);
    background: var(--surface2);
    color: var(--text3);
    cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    font-size: 14px;
    transition: all .15s;
    text-decoration: none;
    flex-shrink: 0;
  }
  .contact-btn:hover {
    background: var(--surface3);
    border-color: var(--accent);
    color: var(--accent);
  }
  .contact-btn:hover .contact-tooltip { opacity: 1; pointer-events: auto; transform: translateY(0); }

  .contact-tooltip {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    background: var(--surface3);
    border: 1px solid var(--border2);
    border-radius: 8px;
    padding: 10px 14px;
    white-space: nowrap;
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    color: var(--text2);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-4px);
    transition: opacity .15s, transform .15s;
    z-index: 200;
    box-shadow: 0 8px 24px rgba(0,0,0,.4);
  }
  .contact-tooltip::before {
    content: '';
    position: absolute;
    top: -5px; right: 10px;
    width: 8px; height: 8px;
    background: var(--surface3);
    border-left: 1px solid var(--border2);
    border-top: 1px solid var(--border2);
    transform: rotate(45deg);
  }
  .contact-tooltip .ct-label {
    font-size: 9px;
    font-weight: 700;
    letter-spacing: 1px;
    text-transform: uppercase;
    color: var(--text3);
    margin-bottom: 4px;
  }
  .contact-tooltip .ct-email {
    color: var(--accent);
    font-weight: 600;
  }
  .btn {
    padding: 6px 14px;
    border-radius: 7px;
    border: 1px solid var(--border2);
    background: var(--surface2);
    color: var(--text);
    font-family: 'Syne', sans-serif;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all .15s;
    display: flex; align-items: center; gap: 6px;
  }
  .btn:hover { background: var(--surface3); border-color: var(--accent); color: var(--accent); }
  .btn.primary {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff;
  }
  .btn.primary:hover { background: var(--accent2); border-color: var(--accent2); color: #fff; }
  .btn.success {
    background: var(--green-dim);
    border-color: var(--green);
    color: var(--green);
  }
  .btn.danger {
    background: var(--red-dim);
    border-color: var(--red);
    color: var(--red);
  }

  /* ── Main layout ── */
  .main {
    display: flex;
    flex: 1;
    overflow: hidden;
  }

  /* ── Left sidebar ── */
  .sidebar {
    width: 220px;
    flex-shrink: 0;
    border-right: 1px solid var(--border);
    background: var(--surface);
    display: flex;
    flex-direction: column;
    overflow-y: auto;
    padding: 16px 12px;
    gap: 16px;
  }
  .sidebar-title {
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 1.5px;
    text-transform: uppercase;
    color: var(--text3);
    padding: 0 4px;
  }
  .node-palette {
    display: flex;
    flex-direction: column;
    gap: 6px;
  }
  .palette-node {
    padding: 10px 12px;
    border-radius: 8px;
    border: 1px solid var(--border);
    cursor: grab;
    font-size: 13px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: all .15s;
    user-select: none;
  }
  .palette-node:active { cursor: grabbing; }
  .palette-node.root { background: var(--node-root-bg); border-color: var(--node-root); color: var(--node-root); }
  .palette-node.intermediate { background: var(--node-inter-bg); border-color: var(--node-inter); color: var(--node-inter); }
  .palette-node.leaf { background: var(--node-leaf-bg); border-color: var(--node-leaf); color: var(--node-leaf); }
  .palette-node.cross { background: var(--node-cross-bg); border-color: var(--node-cross); color: var(--node-cross); }
  .palette-node:hover { transform: translateX(3px); }
  .palette-node .icon { font-size: 16px; }

  .sidebar-section {
    display: flex;
    flex-direction: column;
    gap: 6px;
  }
  .sidebar-divider {
    height: 1px;
    background: var(--border);
    margin: 4px 0;
  }

  /* ── Canvas area ── */
  .canvas-wrap {
    flex: 1;
    position: relative;
    overflow: hidden;
    background: var(--bg);
    background-image:
      radial-gradient(circle at 1px 1px, var(--border) 1px, transparent 0);
    background-size: 28px 28px;
  }
  #canvas {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
  }
  svg#connections {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    pointer-events: none;
    z-index: 1;
  }
  .canvas-hint {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    color: var(--text3);
    pointer-events: none;
    z-index: 0;
  }
  .canvas-hint .hint-icon { font-size: 48px; margin-bottom: 12px; opacity: 0.4; }
  .canvas-hint p { font-size: 13px; line-height: 1.7; }

  /* ── Tree Node ── */
  .tree-node {
    position: absolute;
    width: 250px;
    border-radius: 12px;
    border: 2px solid var(--border);
    background: var(--surface);
    cursor: move;
    z-index: 10;
    transition: box-shadow .15s, border-color .15s;
    user-select: none;
  }
  .tree-node:hover { box-shadow: 0 0 0 1px var(--border2), 0 8px 24px rgba(0,0,0,.4); }
  .tree-node.selected { z-index: 20; }
  .tree-node.selected.root { border-color: var(--node-root); box-shadow: 0 0 0 3px rgba(239,68,68,.15); }
  .tree-node.selected.intermediate { border-color: var(--node-inter); box-shadow: 0 0 0 3px rgba(245,158,11,.15); }
  .tree-node.selected.leaf { border-color: var(--node-leaf); box-shadow: 0 0 0 3px rgba(52,211,153,.15); }
  .tree-node.selected.cross { border-color: var(--node-cross); box-shadow: 0 0 0 3px rgba(167,139,250,.15); }

  .node-header {
    padding: 8px 12px 8px;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 4px 8px;
    border-bottom: 1px solid var(--border);
  }
  .node-type-badge {
    font-size: 9px;
    font-weight: 700;
    letter-spacing: 1px;
    text-transform: uppercase;
    padding: 2px 7px;
    border-radius: 4px;
  }
  .root .node-type-badge { background: var(--node-root-bg); color: var(--node-root); border: 1px solid var(--node-root); }
  .intermediate .node-type-badge { background: var(--node-inter-bg); color: var(--node-inter); border: 1px solid var(--node-inter); }
  .leaf .node-type-badge { background: var(--node-leaf-bg); color: var(--node-leaf); border: 1px solid var(--node-leaf); }
  .cross .node-type-badge { background: var(--node-cross-bg); color: var(--node-cross); border: 1px solid var(--node-cross); }

  .node-name {
    font-size: 13px;
    font-weight: 700;
    color: var(--text);
    order: 3;
    width: 100%;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }
  .node-actions {
    display: flex;
    gap: 4px;
    margin-left: auto;
  }
  .node-action-btn {
    width: 22px; height: 22px;
    border-radius: 5px;
    border: 1px solid var(--border);
    background: none;
    color: var(--text3);
    cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    font-size: 11px;
    transition: all .1s;
  }
  .node-action-btn:hover { background: var(--surface3); color: var(--text); border-color: var(--border2); }
  .node-action-btn.del:hover { background: var(--red-dim); color: var(--red); border-color: var(--red); }

  .node-body {
    padding: 10px 12px;
  }
  .node-cert-area {
    border: 1px dashed var(--border2);
    border-radius: 7px;
    padding: 8px;
    text-align: center;
    cursor: pointer;
    transition: all .15s;
    font-size: 11px;
    color: var(--text3);
    min-height: 52px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 4px;
  }
  .node-cert-area:hover { border-color: var(--accent); color: var(--accent); background: rgba(79,142,247,.05); }
  .node-cert-area.has-cert { border-style: solid; }
  .root .node-cert-area.has-cert { border-color: var(--node-root); background: var(--node-root-bg); }
  .intermediate .node-cert-area.has-cert { border-color: var(--node-inter); background: var(--node-inter-bg); }
  .leaf .node-cert-area.has-cert { border-color: var(--node-leaf); background: var(--node-leaf-bg); }
  .cross .node-cert-area.has-cert { border-color: var(--node-cross); background: var(--node-cross-bg); }

  .cert-info { font-size: 10px; font-family: 'JetBrains Mono', monospace; line-height: 1.6; color: var(--text2); text-align: left; width: 100%; }
  .cert-info .cn { font-weight: 700; color: var(--text); font-size: 11px; }
  .cert-info .exp { font-size: 9px; }
  .cert-status-dot {
    width: 6px; height: 6px;
    border-radius: 50%;
    flex-shrink: 0;
    display: inline-block;
    margin-right: 4px;
  }

  .node-connect-btn {
    margin-top: 8px;
    width: 100%;
    padding: 5px;
    border-radius: 6px;
    border: 1px dashed var(--border2);
    background: none;
    color: var(--text3);
    font-size: 11px;
    font-family: 'Syne', sans-serif;
    cursor: pointer;
    transition: all .15s;
  }
  .node-connect-btn:hover { border-color: var(--accent); color: var(--accent); background: rgba(79,142,247,.05); }
  .node-connect-btn.connecting { border-color: var(--yellow); color: var(--yellow); background: rgba(251,191,36,.05); }

  /* Connection line */
  .conn-line { stroke: var(--border2); stroke-width: 2; fill: none; stroke-dasharray: 6 3; }
  .conn-line.valid { stroke: var(--green); stroke-dasharray: none; }
  .conn-line.invalid { stroke: var(--red); stroke-dasharray: none; }

  /* ── Right panel ── */
  .right-panel {
    width: 300px;
    flex-shrink: 0;
    border-left: 1px solid var(--border);
    background: var(--surface);
    display: flex;
    flex-direction: column;
    overflow-y: auto;
  }
  .panel-section {
    padding: 16px;
    border-bottom: 1px solid var(--border);
  }
  .panel-section-title {
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 1px;
    text-transform: uppercase;
    color: var(--text3);
    margin-bottom: 12px;
  }
  .detail-row {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 8px;
    gap: 8px;
  }
  .detail-label {
    font-size: 11px;
    color: var(--text3);
    font-family: 'JetBrains Mono', monospace;
    flex-shrink: 0;
    padding-top: 1px;
  }
  .detail-value {
    font-size: 11px;
    color: var(--text2);
    font-family: 'JetBrains Mono', monospace;
    text-align: right;
    word-break: break-all;
  }
  .detail-value.ok { color: var(--green); }
  .detail-value.err { color: var(--red); }

  .form-group {
    margin-bottom: 10px;
  }
  .form-label {
    font-size: 11px;
    color: var(--text3);
    margin-bottom: 4px;
    display: block;
    font-weight: 600;
  }
  .form-input {
    width: 100%;
    padding: 7px 10px;
    border-radius: 6px;
    border: 1px solid var(--border);
    background: var(--surface2);
    color: var(--text);
    font-family: 'JetBrains Mono', monospace;
    font-size: 12px;
    outline: none;
    transition: border-color .15s;
  }
  .form-input:focus { border-color: var(--accent); }
  .form-select {
    width: 100%;
    padding: 7px 10px;
    border-radius: 6px;
    border: 1px solid var(--border);
    background: var(--surface2);
    color: var(--text);
    font-family: 'JetBrains Mono', monospace;
    font-size: 12px;
    outline: none;
  }

  .verify-result {
    border-radius: 8px;
    padding: 10px 12px;
    font-size: 11px;
    font-family: 'JetBrains Mono', monospace;
    line-height: 1.7;
    margin-top: 8px;
    display: none;
    max-height: 340px;
    overflow-y: auto;
  }
  .verify-result.pass { background: var(--green-dim); border: 1px solid var(--green); color: var(--green); display: block; }
  .verify-result.fail { background: var(--red-dim); border: 1px solid var(--red); color: var(--red); display: block; }
  .verify-result.warn { background: var(--yellow-dim); border: 1px solid var(--yellow); color: var(--yellow); display: block; }

  /* ── Log / bottom strip ── */
  .log-strip {
    height: 28px;
    border-top: 1px solid var(--border);
    background: var(--surface);
    display: flex;
    align-items: center;
    padding: 0 16px;
    gap: 10px;
    flex-shrink: 0;
    overflow: hidden;
  }
  .log-dot {
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--green);
    flex-shrink: 0;
    animation: pulse 2s infinite;
  }
  @keyframes pulse { 0%,100%{opacity:1}50%{opacity:.3} }
  .log-text {
    font-size: 11px;
    font-family: 'JetBrains Mono', monospace;
    color: var(--text3);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  /* ── Modal ── */
  .modal-backdrop {
    display: none;
    position: fixed; inset: 0;
    background: rgba(0,0,0,.7);
    z-index: 1000;
    align-items: center;
    justify-content: center;
  }
  .modal-backdrop.show { display: flex; }
  .modal {
    background: var(--surface);
    border: 1px solid var(--border2);
    border-radius: 14px;
    width: 540px;
    max-height: 80vh;
    overflow-y: auto;
    padding: 24px;
    box-shadow: 0 24px 60px rgba(0,0,0,.5);
  }
  .modal-title {
    font-size: 18px;
    font-weight: 800;
    margin-bottom: 20px;
    color: var(--text);
  }
  .modal-actions {
    display: flex;
    gap: 8px;
    justify-content: flex-end;
    margin-top: 20px;
  }

  .dropzone {
    border: 2px dashed var(--border2);
    border-radius: 10px;
    padding: 24px;
    text-align: center;
    cursor: pointer;
    transition: all .15s;
    color: var(--text3);
    font-size: 13px;
  }
  .dropzone:hover, .dropzone.dragover {
    border-color: var(--accent);
    background: rgba(79,142,247,.06);
    color: var(--accent);
  }
  .dropzone .dz-icon { font-size: 32px; margin-bottom: 8px; }
  #dropzone-input { display: none; }

  .cert-preview {
    margin-top: 12px;
    background: var(--surface2);
    border-radius: 8px;
    padding: 12px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    color: var(--text2);
    line-height: 1.8;
    display: none;
  }
  .cert-preview.show { display: block; }
  .cert-preview .field-name { color: var(--text3); }
  .cert-preview .field-val { color: var(--text); }

  /* Generate modal */
  .gen-node-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
    max-height: 300px;
    overflow-y: auto;
    margin-bottom: 16px;
  }
  .gen-node-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 12px;
    background: var(--surface2);
    border-radius: 8px;
    border: 1px solid var(--border);
  }
  .gen-node-item .status-icon { font-size: 16px; width: 20px; text-align: center; }
  .gen-node-item .node-label { font-size: 12px; font-family: 'JetBrains Mono', monospace; flex: 1; }
  .gen-node-item .dl-btn {
    padding: 4px 10px;
    border-radius: 5px;
    border: 1px solid var(--border2);
    background: none;
    color: var(--text2);
    font-size: 11px;
    cursor: pointer;
    font-family: 'Syne', sans-serif;
    font-weight: 600;
    transition: all .15s;
    display: none;
  }
  .gen-node-item .dl-btn.show { display: block; }
  .gen-node-item .dl-btn:hover { border-color: var(--accent); color: var(--accent); }

  .algo-badge {
    font-size: 10px;
    font-weight: 700;
    padding: 2px 8px;
    border-radius: 4px;
    white-space: nowrap;
    flex-shrink: 0;
  }
  .algo-badge.rsa { background: rgba(79,142,247,.15); color: var(--accent); border: 1px solid var(--accent2); }
  .algo-badge.ecdsa { background: var(--purple-dim); color: var(--purple); border: 1px solid var(--purple); }
  .algo-badge.ed25519 { background: var(--green-dim); color: var(--green); border: 1px solid var(--green); }
  .dday-badge {
    display: inline-block; font-size: 9px; font-weight: 700;
    padding: 1px 6px; border-radius: 3px; white-space: nowrap; flex-shrink: 0;
  }
  .dday-badge.ok       { background: var(--green-dim);  color: var(--green);  border: 1px solid var(--green); }
  .dday-badge.warn     { background: rgba(255,180,0,.15); color: #ffb400;     border: 1px solid #ffb400; }
  .dday-badge.critical { background: var(--red-dim);    color: var(--red);    border: 1px solid var(--red); }
  .node-dday-dot {
    width: 7px; height: 7px; border-radius: 50%; flex-shrink: 0; margin-left: 2px;
  }
  .node-dday-dot.warn     { background: #ffb400; box-shadow: 0 0 4px #ffb400; }
  .node-dday-dot.critical { background: var(--red); box-shadow: 0 0 4px var(--red); }

  .gen-node-item .algo-select {
    padding: 3px 7px;
    border-radius: 5px;
    border: 1px solid var(--border2);
    background: var(--surface3);
    color: var(--text2);
    font-size: 11px;
    font-family: 'JetBrains Mono', monospace;
    cursor: pointer;
    outline: none;
    display: none;
  }
  .gen-node-item .algo-select.show { display: block; }
  .gen-node-item .algo-select:focus { border-color: var(--accent); color: var(--text); }

  .progress-bar-wrap {
    height: 4px;
    background: var(--border);
    border-radius: 2px;
    margin-bottom: 16px;
    overflow: hidden;
  }
  .progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--accent), var(--purple));
    border-radius: 2px;
    transition: width .4s ease;
    width: 0%;
  }

  /* Scrollbar */
  ::-webkit-scrollbar { width: 5px; height: 5px; }
  ::-webkit-scrollbar-track { background: transparent; }
  ::-webkit-scrollbar-thumb { background: var(--border2); border-radius: 3px; }
  ::-webkit-scrollbar-thumb:hover { background: var(--text3); }

  .tag { display: inline-block; padding: 2px 8px; border-radius: 4px; font-size: 10px; font-weight: 700; letter-spacing:.5px; }
  .tag.ok { background: var(--green-dim); color: var(--green); }
  .tag.err { background: var(--red-dim); color: var(--red); }
  .tag.warn { background: var(--yellow-dim); color: var(--yellow); }
  .tag.info { background: rgba(79,142,247,.15); color: var(--accent); }

  .empty-panel {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    flex: 1;
    color: var(--text3);
    font-size: 12px;
    text-align: center;
    gap: 8px;
    padding: 24px;
  }
  .empty-panel .icon { font-size: 32px; opacity: .3; }

  /* OpenSSL Commands Modal */
  .openssl-modal {
    background: var(--surface);
    border: 1px solid var(--border2);
    border-radius: 14px;
    width: 720px;
    max-width: 95vw;
    max-height: 82vh;
    padding: 24px;
    box-shadow: 0 24px 60px rgba(0,0,0,.5);
    display: flex;
    flex-direction: column;
    gap: 16px;
  }
  .openssl-body {
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 10px;
  }
  .openssl-section { position: relative; }
  .openssl-pre {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 14px 48px 14px 14px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 12px;
    color: var(--text);
    white-space: pre;
    overflow-x: auto;
    margin: 0;
    line-height: 1.75;
  }
  .openssl-copy-btn {
    position: absolute;
    top: 8px;
    right: 8px;
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: 4px;
    color: var(--text2);
    font-size: 10px;
    padding: 3px 8px;
    cursor: pointer;
    font-family: 'JetBrains Mono', monospace;
    transition: all .1s;
  }
  .openssl-copy-btn:hover { background: var(--surface3); color: var(--text); }
  .openssl-empty {
    text-align: center;
    color: var(--text3);
    font-size: 13px;
    padding: 32px;
  }

  /* ── Preset Modal ── */
  .preset-modal {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 24px;
    width: 520px;
    max-width: 95vw;
    max-height: 90vh;
    overflow-y: auto;
  }
  .preset-cards {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    margin: 14px 0;
  }
  .preset-card {
    background: var(--surface2);
    border: 1.5px solid var(--border);
    border-radius: 8px;
    padding: 14px 10px;
    cursor: pointer;
    transition: border-color .15s, background .15s;
    text-align: center;
  }
  .preset-card:hover { border-color: var(--accent); background: var(--surface3); }
  .preset-card.selected { border-color: var(--accent); background: rgba(79,142,247,.1); }
  .preset-card-icon { font-size: 22px; margin-bottom: 7px; }
  .preset-card-name {
    font-size: 12px;
    font-weight: 700;
    color: var(--text);
    font-family: 'Syne', sans-serif;
    margin-bottom: 5px;
  }
  .preset-card-desc { font-size: 10px; color: var(--text2); line-height: 1.4; margin-bottom: 6px; }
  .preset-chain-preview {
    font-size: 10px;
    color: var(--text3);
    font-family: 'JetBrains Mono', monospace;
    line-height: 1.7;
  }
  .preset-ext-badges { display: flex; flex-wrap: wrap; gap: 4px; justify-content: center; margin-top: 6px; }
  .preset-ext-badge {
    font-size: 9px;
    padding: 1px 5px;
    border-radius: 3px;
    background: var(--surface3);
    border: 1px solid var(--border2);
    color: var(--text2);
    font-family: 'JetBrains Mono', monospace;
  }