:root {
  --bg: #eef2f7;
  --panel: #ffffff;
  --line: #d6dce5;
  --text: #111827;
  --muted: #6b7280;
  --accent: #2563eb;
  --danger: #dc2626;
}
* { box-sizing: border-box; }
html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background: var(--bg);
}
button, input, textarea {
  font: inherit;
}
button {
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 10px;
  padding: 10px 12px;
  cursor: pointer;
}
button:hover { background: #f9fafb; }
button.primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
button.primary:hover { filter: brightness(0.95); }
button.danger {
  color: #fff;
  background: var(--danger);
  border-color: var(--danger);
}
.app-shell {
  display: grid;
  grid-template-columns: 280px 1fr;
  grid-template-rows: 72px 1fr;
  height: 100vh;
}
.topbar {
  grid-column: 1 / 3;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 18px;
  background: var(--panel);
  border-bottom: 1px solid var(--line);
}
.brand {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.brand span {
  color: var(--muted);
  font-size: 13px;
}
.top-actions {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: flex-end;
}
.sidebar {
  overflow: auto;
  padding: 16px;
  border-right: 1px solid var(--line);
}
.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 14px;
  margin-bottom: 14px;
}
.panel h2 {
  margin: 0 0 12px;
  font-size: 15px;
}
.panel label {
  display: grid;
  gap: 6px;
  font-size: 14px;
  margin-bottom: 10px;
}
.panel input[type="number"],
.panel textarea,
.panel input[type="text"] {
  width: 100%;
  padding: 10px;
  border-radius: 10px;
  border: 1px solid var(--line);
}
.tool-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}
.tool.active {
  background: #dbeafe;
  border-color: #93c5fd;
  color: #1d4ed8;
  font-weight: 600;
}
.workspace {
  overflow: auto;
  padding: 18px;
}
.canvas-wrap {
  min-height: calc(100vh - 110px);
  display: flex;
  align-items: flex-start;
  justify-content: flex-start;
}
#svgCanvas {
  background: #fff;
  border: 1px solid var(--line);
  box-shadow: 0 10px 30px rgba(15, 23, 42, 0.08);
  touch-action: none;
}
.small-note ul {
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.7;
}
.text-editor {
  position: fixed;
  z-index: 30;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  box-shadow: 0 20px 45px rgba(0, 0, 0, 0.12);
  padding: 12px;
  width: 280px;
}
.text-editor.hidden { display: none; }
.text-editor textarea {
  width: 100%;
  min-height: 100px;
  border-radius: 10px;
  border: 1px solid var(--line);
  padding: 10px;
}
.text-editor-actions {
  margin-top: 10px;
  display: flex;
  gap: 8px;
  justify-content: flex-end;
}
.selection-box {
  fill: none;
  stroke: #2563eb;
  stroke-width: 1.5;
  stroke-dasharray: 6 4;
  pointer-events: none;
}
.handle {
  fill: #fff;
  stroke: #2563eb;
  stroke-width: 1.5;
  cursor: pointer;
}
@media (max-width: 960px) {
  .app-shell {
    grid-template-columns: 1fr;
    grid-template-rows: 72px auto 1fr;
  }
  .topbar { grid-column: 1; }
  .sidebar {
    border-right: none;
    border-bottom: 1px solid var(--line);
  }
}