:root {
  --bg: #f4f5f7;
  --surface: #ffffff;
  --surface2: #edeef1;
  --border: #d1d5db;
  --accent: #4a6cf7;
  --accent2: #7c5cbf;
  --accent3: #16a06b;
  --text: #1a1d24;
  --text2: #5f6878;
  --text3: #8892a4;
  --line: #b0b8c8;
  --overlay: #0004;
  --shadow: #0001;
  --badge-bg: #4a6cf712;
  --badge-border: #4a6cf730;
  --root-gradient: linear-gradient(135deg, #ffffff, #eef1fb);
}
:root[data-theme="dark"] {
  --bg: #0d0f14;
  --surface: #161920;
  --surface2: #1e222c;
  --border: #2a2f3d;
  --accent: #6c8fff;
  --accent2: #a78bfa;
  --accent3: #34d399;
  --text: #e8eaf0;
  --text2: #8892a4;
  --text3: #5a6272;
  --line: #2e3550;
  --overlay: #000a;
  --shadow: #000c;
  --badge-bg: #6c8fff18;
  --badge-border: #6c8fff33;
  --root-gradient: linear-gradient(135deg, #161920, #1a1f2e);
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html, body { width: 100%; height: 100%; overflow: hidden; background: var(--bg); color: var(--text); font-family: 'Inter', sans-serif; display: flex; flex-direction: column; }

header { display: flex; align-items: center; gap: 14px; padding: 11px 20px; background: var(--surface); border-bottom: 1px solid var(--border); flex-shrink: 0; z-index: 100; }
header h1 { font-family: 'Inter', sans-serif; font-size: 14px; font-weight: 800; letter-spacing: 0.08em; text-transform: uppercase; }
.badge { font-size: 10px; font-weight: 600; text-transform: uppercase; letter-spacing: 0.08em; padding: 3px 8px; border-radius: 4px; background: var(--badge-bg); color: var(--accent); border: 1px solid var(--badge-border); }
.toolbar { margin-left: auto; display: flex; gap: 6px; align-items: center; }
.btn { font-family: 'Inter', sans-serif; font-size: 12px; font-weight: 500; padding: 5px 12px; border-radius: 6px; border: 1px solid var(--border); background: var(--surface2); color: var(--text2); cursor: pointer; transition: border-color 0.12s, color 0.12s; white-space: nowrap; }
.btn:hover { border-color: var(--accent); color: var(--accent); }
.btn:disabled { opacity: 0.4; cursor: default; pointer-events: none; }
.btn.primary { background: var(--accent); color: #fff; border-color: var(--accent); }
.btn.primary:hover { background: #8aa8ff; }
.btn.danger { background: #e05c5c; color: #fff; border-color: #e05c5c; }
.btn.danger:hover { background: #c94444; }
.zoom-label { font-size: 11px; color: var(--text3); min-width: 38px; text-align: center; }
.sep { width: 1px; height: 20px; background: var(--border); margin: 0 2px; }

#viewport { flex: 1; position: relative; overflow: hidden; cursor: default; }
#viewport.panning { cursor: grabbing !important; }
#viewport.space-held { cursor: grab; }

#canvas { position: absolute; top: 0; left: 0; transform-origin: 0 0; }

svg#lines { position: absolute; top: 0; left: 0; overflow: visible; pointer-events: none; color: var(--line); }

.node {
  position: absolute; width: 202px;
  top: 0; left: 0;
  background: var(--surface); border: 1.5px solid var(--border); border-radius: 10px;
  padding: 9px 11px; cursor: grab; user-select: none;
  display: flex; align-items: center; gap: 9px;
  transition: border-color 0.12s;
  will-change: transform;
}
.node:hover { border-color: var(--accent); outline: 3px solid var(--badge-bg); z-index: 10; }
.node.dragging { opacity: 0.75; cursor: grabbing; z-index: 2000; }
.node.drop-target { border-color: var(--accent3) !important; outline: 3px solid color-mix(in srgb, var(--accent3) 20%, transparent); background: color-mix(in srgb, var(--accent3) 4%, transparent); }
.node.root-node { border-color: var(--accent); background: var(--root-gradient); }

.avatar { width: 36px; height: 36px; border-radius: 50%; flex-shrink: 0; border: 2px solid var(--border); background: var(--surface2); display: flex; align-items: center; justify-content: center; font-family: 'Inter', sans-serif; font-size: 11px; font-weight: 700; color: var(--text2); }
.root-node .avatar { border-color: var(--accent); }

.node-info { min-width: 0; flex: 1; }
.node-name { font-family: 'Inter', sans-serif; font-size: 11px; font-weight: 700; color: var(--text); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.node-title { font-size: 9.5px; color: var(--text3); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; margin-top: 1px; }
.node-reports { font-size: 9px; color: var(--accent2); margin-top: 2px; font-weight: 500; }

.node-actions { display: none; position: absolute; top: -7px; right: -7px; gap: 2px; }
.node:hover .node-actions { display: flex; }
.action-btn { width: 16px; height: 16px; border-radius: 50%; border: 1px solid var(--border); background: var(--surface2); color: var(--text2); cursor: pointer; display: flex; align-items: center; justify-content: center; font-size: 9px; transition: background 0.12s, color 0.12s; }
.action-btn:hover { background: #e05c5c; color: #fff; border-color: #e05c5c; }
.toggle-btn:hover { background: var(--accent); color: #fff; border-color: var(--accent); }
.add-report-btn { display: none; position: absolute; bottom: -7px; left: 50%; transform: translateX(-50%); }
.add-report-btn.add-report-left { bottom: auto; left: -7px; top: 50%; transform: translateY(-50%); }
.add-report-btn:hover { background: var(--accent); color: #fff; border-color: var(--accent); }
.node:hover .add-report-btn { display: flex; }

.modal-overlay { display: none; position: fixed; inset: 0; background: var(--overlay); z-index: 800; align-items: center; justify-content: center; }
.modal-overlay.open { display: flex; }
.modal { background: var(--surface); border: 1px solid var(--border); border-radius: 14px; padding: 26px; width: 340px; box-shadow: 0 24px 80px var(--shadow); }
.modal h2 { font-family: 'Inter', sans-serif; font-size: 15px; margin-bottom: 16px; }
.form-group { margin-bottom: 12px; }
.form-group label { font-size: 10px; color: var(--text2); font-weight: 600; text-transform: uppercase; letter-spacing: 0.07em; display: block; margin-bottom: 4px; }
.form-group input, .form-group select { width: 100%; padding: 7px 10px; background: var(--surface2); border: 1px solid var(--border); border-radius: 6px; color: var(--text); font-family: 'Inter', sans-serif; font-size: 13px; }
.form-group input:focus, .form-group select:focus { outline: none; border-color: var(--accent); }
.modal-actions { display: flex; gap: 8px; justify-content: flex-end; margin-top: 18px; }

.hint { position: fixed; bottom: 14px; left: 50%; transform: translateX(-50%); background: var(--surface2); border: 1px solid var(--border); border-radius: 20px; padding: 5px 16px; font-size: 10px; color: var(--text3); pointer-events: none; z-index: 50; white-space: nowrap; }
.modal-wide { width: 520px; }
.modal-desc { font-size: 12px; color: var(--text2); margin-bottom: 12px; line-height: 1.5; }
.modal textarea { width: 100%; height: 220px; padding: 10px; background: var(--surface2); border: 1px solid var(--border); border-radius: 6px; color: var(--text); font-family: 'DM Mono', 'Fira Mono', monospace; font-size: 11px; line-height: 1.5; resize: vertical; }
.modal textarea:focus { outline: none; border-color: var(--accent); }
.modal-error { font-size: 11px; color: #e05c5c; min-height: 16px; margin-top: 6px; }

.save-list { list-style: none; margin: 0; padding: 0; overflow-y: auto; max-height: 260px; }
.save-list li { display: flex; align-items: center; justify-content: space-between; padding: 8px 10px; border-radius: 8px; cursor: pointer; transition: background 0.1s; }
.save-list li:hover { background: var(--surface2); }
.save-list .save-name { font-family: 'Inter', sans-serif; font-size: 11px; font-weight: 700; color: var(--text); }
.save-list .save-date { font-size: 9.5px; color: var(--text3); margin-top: 1px; }
.save-list .save-delete { background: none; border: none; color: var(--text3); cursor: pointer; font-size: 13px; padding: 2px 6px; line-height: 1; transition: color 0.15s; flex-shrink: 0; }
.save-list .save-delete:hover { color: #e05c5c; }
.save-empty { text-align: center; padding: 24px 0; font-size: 11px; color: var(--text3); cursor: default; }