:root {
  --bg: #f6f7f9;
  --card: #ffffff;
  --border: #e3e6ea;
  --foreground: #1a1d21;
  --muted: #6b7280;
  --muted-bg: #f1f3f5;
  --primary: #1a1d21;
  --primary-foreground: #ffffff;
  --accent: #eef0f3;
  --danger: #d64545;
  --radius: 10px;
  --radius-sm: 7px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--foreground);
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 14px;
  line-height: 1.45;
}

h1 { font-size: 20px; font-weight: 600; letter-spacing: -0.01em; margin: 0; }
h2 { font-size: 14px; font-weight: 600; letter-spacing: -0.01em; margin: 0 0 12px; }

.muted { color: var(--muted); }
.small { font-size: 12px; }
.strong { font-weight: 600; }
.danger { color: var(--danger); }
.pad-top { padding-top: 8px; }

/* Top bar -------------------------------------------------------------- */
.topbar {
  border-bottom: 1px solid var(--border);
  background: var(--card);
}
.topbar-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 24px;
}
.subtitle { font-size: 12px; color: var(--muted); margin: 2px 0 0; }
.topbar-actions { display: flex; gap: 8px; align-items: center; }

/* Buttons -------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--foreground);
  border-radius: var(--radius-sm);
  padding: 7px 13px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.12s, opacity 0.12s;
}
.btn:hover { background: var(--accent); }
.btn-primary {
  background: var(--primary);
  color: var(--primary-foreground);
  border-color: var(--primary);
}
.btn-primary:hover { background: var(--primary); opacity: 0.9; }
.btn-sm { padding: 6px 11px; font-size: 12px; }
.btn-block { width: 100%; margin-top: 8px; }

/* Layout --------------------------------------------------------------- */
.layout {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 20px;
  padding: 20px 24px;
}
@media (max-width: 900px) {
  .layout { grid-template-columns: 1fr; }
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
}
.canvas-card { padding: 12px; }
.sidebar { display: flex; flex-direction: column; gap: 16px; }

/* Empty state / stage -------------------------------------------------- */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  aspect-ratio: 16 / 9;
  border: 2px dashed var(--border);
  border-radius: var(--radius-sm);
  background: var(--muted-bg);
  padding: 32px;
  transition: background 0.12s, border-color 0.12s;
}
.empty-state.drag { background: var(--accent); border-color: var(--primary); }
.empty-title { font-size: 16px; font-weight: 500; }
.empty-hint { margin-top: 4px; font-size: 12px; color: var(--muted); }

.stage { position: relative; width: 100%; user-select: none; }
.stage img { display: block; width: 100%; height: auto; border-radius: var(--radius-sm); }
.overlay {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  cursor: crosshair;
}

/* Forms ---------------------------------------------------------------- */
.row { display: flex; gap: 8px; }
.field-label { display: block; font-size: 12px; font-weight: 500; margin: 8px 0 4px; }
.input, .select, .name-input {
  width: 100%;
  border: 1px solid var(--border);
  background: var(--card);
  border-radius: var(--radius-sm);
  padding: 7px 9px;
  font-size: 14px;
  color: var(--foreground);
}
.row .input, .row .select { flex: 1; }
.name-input { font-weight: 600; }
.save-status { margin-top: 8px; font-size: 12px; color: var(--muted); }

.info-box {
  background: var(--muted-bg);
  border-radius: var(--radius-sm);
  padding: 9px 11px;
  font-size: 12px;
  margin-top: 10px;
  display: grid;
  gap: 2px;
}

/* Tool grid ------------------------------------------------------------ */
.tool-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; }
.tool-btn {
  border: 1px solid var(--border);
  background: var(--card);
  border-radius: var(--radius-sm);
  padding: 9px;
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.12s;
}
.tool-btn:hover { background: var(--accent); }
.tool-btn.active {
  background: var(--primary);
  color: var(--primary-foreground);
  border-color: var(--primary);
}

/* Lists ---------------------------------------------------------------- */
.measure-list, .project-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 6px; }
.measure-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  background: var(--muted-bg);
  border-radius: var(--radius-sm);
  padding: 7px 10px;
  font-size: 12px;
}
.icon-btn {
  border: none;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font-size: 13px;
  line-height: 1;
  padding: 2px 4px;
}
.icon-btn:hover { color: var(--danger); }

.project-item {
  display: flex;
  align-items: stretch;
  gap: 6px;
  background: var(--muted-bg);
  border-radius: var(--radius-sm);
  overflow: hidden;
}
.project-open {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 2px;
  border: none;
  background: transparent;
  cursor: pointer;
  padding: 8px 10px;
  text-align: left;
}
.project-open:hover { background: var(--accent); }
.project-name { font-size: 13px; font-weight: 500; }
.project-meta { font-size: 11px; color: var(--muted); }
.project-delete {
  border: none;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font-size: 18px;
  line-height: 1;
  padding: 0 12px;
}
.project-delete:hover { color: var(--danger); }

/* Tips ----------------------------------------------------------------- */
.tips { margin: 0; padding-left: 18px; color: var(--muted); font-size: 12px; display: grid; gap: 4px; }

/* Toast ---------------------------------------------------------------- */
.toast {
  position: fixed;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--primary);
  color: var(--primary-foreground);
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.18);
  z-index: 50;
}
.toast-error { background: var(--danger); }