/* ============================================================
   EPSPilot AI — Sidebar
   ============================================================ */

.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--sidebar-width);
  height: 100vh;
  background: var(--color-surface);
  border-right: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  z-index: var(--z-sidebar);
  transition: transform var(--transition-slow);
  overflow-y: auto;
  overflow-x: hidden;
}

.sidebar__brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-6) var(--space-5);
  border-bottom: 1px solid var(--color-border);
}

.sidebar__title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: var(--color-primary);
  letter-spacing: var(--letter-spacing-tight);
}

.sidebar__nav {
  flex: 1;
  padding: var(--space-4) var(--space-3);
}

.sidebar__link {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  transition: all var(--transition-fast);
  margin-bottom: var(--space-1);
}

.sidebar__link:hover {
  background: var(--color-surface-hover);
  color: var(--color-text);
}

.sidebar__link[aria-current="page"],
.sidebar__link.active {
  background: var(--color-primary-subtle);
  color: var(--color-primary);
  font-weight: var(--font-weight-semibold);
}

.sidebar__link[aria-current="page"] .icon,
.sidebar__link.active .icon {
  color: var(--color-primary);
}

.sidebar__footer {
  padding: var(--space-4) var(--space-5);
  border-top: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.sidebar__theme-btn {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  transition: all var(--transition-fast);
  width: 100%;
}

.sidebar__theme-btn:hover {
  background: var(--color-surface-hover);
  color: var(--color-text);
}

.sidebar__mode {
  display: flex;
  justify-content: center;
}

/* Sidebar overlay for mobile */
.sidebar-overlay {
  position: fixed;
  inset: 0;
  background: var(--color-backdrop);
  z-index: calc(var(--z-sidebar) - 1);
  opacity: 0;
  transition: opacity var(--transition-base);
  pointer-events: none;
}

.sidebar-overlay.visible {
  opacity: 1;
  pointer-events: auto;
}

/* Icons */
.icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  color: var(--color-text-secondary);
}

.icon-sm {
  width: 16px;
  height: 16px;
}

.icon-lg {
  width: 24px;
  height: 24px;
}

.icon-brand {
  width: 28px;
  height: 28px;
  color: var(--color-primary);
}