.sidebar {
  width: var(--sidebar-width);
  flex-shrink: 0;
  background: var(--color-bg-alt);
  border-right: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
}

.sidebar-header {
  padding: 1.6rem 1.6rem 1.2rem;
  border-bottom: 1px solid var(--color-border);
}

.sidebar-logo {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--color-text);
  display: flex;
  align-items: center;
  gap: 0.5em;
}

.sidebar-logo::before {
  content: "";
  width: 10px;
  height: 10px;
  border: 2px solid var(--color-primary);
  transform: rotate(45deg);
  flex-shrink: 0;
}

.sidebar-body {
  padding: 1.4rem 1rem;
  flex: 1;
}

.sidebar-section-title {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  color: var(--color-text-muted);
  padding: 0 0.6rem;
  margin: 0 0 0.6rem;
}

.sidebar-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.sidebar-list a {
  display: block;
  padding: 0.6rem 0.6rem 0.6rem 0.8rem;
  border-left: 2px solid transparent;
  color: var(--color-text-muted);
  font-size: 0.92rem;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  transition: border-color var(--transition), color var(--transition), background var(--transition);
}

.sidebar-list a:hover {
  color: var(--color-text);
  background: var(--color-surface);
  border-left-color: var(--color-line-strong);
}

.sidebar-list a.active {
  color: var(--color-text);
  border-left-color: var(--color-primary);
  background: var(--color-surface);
  font-weight: 500;
}

.sidebar-note {
  padding: 1rem 1.4rem 1.4rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-text-muted);
  border-top: 1px solid var(--color-border);
}