header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 16px 32px;
  display: flex;
  align-items: center;
  gap: 16px;
  flex-shrink: 0;
}

header h1 { font-size: 20px; font-weight: 600; letter-spacing: -0.3px; }
header p  { font-size: 15px; color: var(--muted); }

.badge {
  background: var(--accent);
  color: white;
  font-size: 13px;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 4px;
  letter-spacing: 0.5px;
}

/* ── Three-column main layout ─────────────────────────────────────── */
.main {
  display: flex;
  flex: 1;
  overflow: hidden;
}

/* LEFT: collapsible flow navigator */
.flow-nav {
  width: 220px;
  min-width: 220px;
  background: var(--surface);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  padding: 16px 0 24px;
  flex-shrink: 0;
}

/* Group container */
.flow-nav-group {
  margin-bottom: 2px;
}

/* Group toggle button */
.flow-nav-group-btn {
  width: 100%;
  background: none;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 8px 16px;
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.1px;
  color: var(--muted);
  text-align: left;
  transition: color 0.15s;
}
.flow-nav-group-btn:hover { color: var(--text); }

.flow-nav-group-arrow {
  font-size: 9px;
  transition: transform 0.2s;
  flex-shrink: 0;
  color: var(--muted);
}
.flow-nav-group.open .flow-nav-group-arrow {
  transform: rotate(90deg);
}

/* Items list — hidden when group is closed */
.flow-nav-items {
  display: none;
  flex-direction: column;
}
.flow-nav-group.open .flow-nav-items {
  display: flex;
}

/* Individual flow items */
.flow-tab {
  padding: 8px 16px 8px 30px;
  font-size: 13px;
  font-weight: 500;
  color: var(--muted);
  cursor: pointer;
  border-left: 2px solid transparent;
  transition: all 0.15s;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.flow-tab:hover { color: var(--text); background: var(--surface2); }
.flow-tab.active {
  color: var(--accent);
  border-left-color: var(--accent);
  background: var(--surface2);
}
.flow-tab.disabled {
  opacity: 0.35;
  cursor: default;
  pointer-events: none;
}

/* MIDDLE + RIGHT wrapper */
.main-right {
  display: flex;
  flex: 1;
  overflow: hidden;
}

/* MIDDLE: step list */
.steps-panel {
  width: 240px;
  min-width: 240px;
  background: var(--surface);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  padding: 24px 0;
  flex-shrink: 0;
}

.steps-label {
  font-size: 11px;
  font-weight: 700;
  color: var(--muted);
  letter-spacing: 1px;
  padding: 0 16px 12px;
  text-transform: uppercase;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* RIGHT: content */
.content-panel {
  flex: 1;
  overflow-y: auto;
  padding: 32px;
  max-width: 900px;
}