/* ============================================================
   Sidebar — brand, progress, nav, footer buttons
   ============================================================ */

.sidebar {
  background: var(--bg-2);
  border-right: 1px solid var(--border);
  padding: 24px 0;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
  z-index: 10;
  display: flex;
  flex-direction: column;
}

.brand {
  padding: 0 24px 20px;
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--mono);
  font-weight: 700;
  font-size: 13px;
  letter-spacing: 0.05em;
  border-bottom: 1px solid var(--border-soft);
  margin-bottom: 16px;
}

.brand-mark {
  width: 24px;
  height: 24px;
  background: var(--accent);
  color: var(--bg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 700;
  border-radius: 2px;
}

.brand-sub {
  color: var(--text-muted);
  font-weight: 400;
  font-size: 11px;
}

.progress-wrap {
  padding: 0 24px 16px;
  border-bottom: 1px solid var(--border-soft);
  margin-bottom: 12px;
}

.progress-label {
  display: flex;
  justify-content: space-between;
  font-family: var(--mono);
  font-size: 10px;
  color: var(--text-muted);
  letter-spacing: 0.05em;
  margin-bottom: 6px;
  text-transform: uppercase;
}

.progress-bar {
  height: 4px;
  background: var(--bg-3);
  border-radius: 2px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  width: 0%;
  transition: width 0.4s ease;
}

.nav-section {
  padding: 12px 24px 6px;
  font-family: var(--mono);
  font-size: 10px;
  color: var(--text-dim);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.nav { flex: 1; }

.nav a {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 7px 24px;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 13.5px;
  font-weight: 500;
  border-left: 2px solid transparent;
  transition: all 0.15s ease;
}

.nav a:hover {
  color: var(--text);
  background: var(--bg-3);
}

.nav a.active {
  color: var(--accent);
  border-left-color: var(--accent);
  background: var(--bg-3);
}

.nav-check {
  width: 12px;
  height: 12px;
  border: 1px solid var(--border);
  border-radius: 2px;
  display: inline-block;
  flex-shrink: 0;
}

.nav a.done .nav-check {
  background: var(--success);
  border-color: var(--success);
  position: relative;
}

.nav a.done .nav-check::after {
  content: '✓';
  color: var(--bg);
  font-size: 10px;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-weight: 700;
}

.sidebar-footer {
  padding: 16px 24px 0;
  border-top: 1px solid var(--border-soft);
  display: flex;
  gap: 8px;
}

.icon-btn {
  flex: 1;
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 7px 10px;
  border-radius: 4px;
  cursor: pointer;
  font-family: var(--mono);
  font-size: 11px;
  transition: all 0.15s;
}

.icon-btn:hover {
  color: var(--text);
  border-color: var(--text-muted);
}