/* ─── App Shell ─── */
.app {
  display: flex;
  min-height: 100vh;
}

/* ─── Sidebar ─── */
.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  height: 100vh;
  width: var(--sidebar-width);
  background: rgba(8, 10, 20, 0.98);
  border-right: 1px solid rgba(255, 255, 255, 0.06);
  z-index: var(--z-sidebar);
  display: flex;
  flex-direction: column;
  transition: width var(--transition-base);
  overflow: hidden;
  backdrop-filter: blur(24px);
}

.sidebar.collapsed {
  width: var(--sidebar-collapsed);
}

/* ─── Sidebar Header ─── */
.sidebar__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 14px 20px 18px;
  height: var(--header-height);
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  flex-shrink: 0;
}

.sidebar__logo {
  display: flex;
  align-items: center;
  gap: 10px;
  overflow: hidden;
  white-space: nowrap;
  text-decoration: none;
}

/* Small tech icon — no filled block */
.sidebar__logo-icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  color: var(--color-accent);
  filter: drop-shadow(0 0 6px rgba(0, 212, 170, 0.5));
  line-height: 1;
  background: none;
  border-radius: 0;
}

/* SENTINEL LEARNING — uppercase brand wordmark */
.sidebar__logo-text {
  font-family: var(--font-display);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: var(--letter-brand);
  text-transform: uppercase;
  color: var(--color-text);
  transition: opacity var(--transition-base);
}

.sidebar.collapsed .sidebar__logo-text {
  opacity: 0;
  pointer-events: none;
  width: 0;
}

.sidebar__toggle {
  width: 26px;
  height: 26px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  border: 1px solid rgba(255, 255, 255, 0.06);
  background: rgba(255, 255, 255, 0.03);
  transition: background var(--transition-fast),
              color var(--transition-fast),
              border-color var(--transition-fast);
}

.sidebar__toggle:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(108, 99, 255, 0.4);
  color: var(--color-text);
}

.sidebar__toggle svg {
  transition: transform var(--transition-base);
}

.sidebar.collapsed .sidebar__toggle svg {
  transform: rotate(180deg);
}

/* ─── Sidebar Nav ─── */
.sidebar__nav {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  padding: var(--space-3) 8px;
}

.sidebar__nav::-webkit-scrollbar { width: 2px; }
.sidebar__nav::-webkit-scrollbar-track { background: transparent; }
.sidebar__nav::-webkit-scrollbar-thumb { background: rgba(255,255,255,.08); border-radius: 2px; }

.nav-section {
  margin-bottom: var(--space-5);
}

.nav-section__label {
  font-family: var(--font-mono);
  font-size: 9px;
  font-weight: var(--weight-semibold);
  text-transform: uppercase;
  letter-spacing: var(--letter-tag);
  color: rgba(152, 152, 184, 0.5);
  padding: 0 10px var(--space-2);
  white-space: nowrap;
  overflow: hidden;
  transition: opacity var(--transition-base);
}

.sidebar.collapsed .nav-section__label {
  opacity: 0;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 10px;
  border-radius: var(--radius-md);
  color: rgba(152, 152, 184, 0.8);
  font-size: 13px;
  font-weight: var(--weight-medium);
  letter-spacing: var(--letter-menu);
  white-space: nowrap;
  transition: background var(--transition-fast),
              color var(--transition-fast),
              border-color var(--transition-fast);
  position: relative;
  cursor: pointer;
  border: 1px solid transparent;
  border-left: 2px solid transparent;
}

.nav-item:hover {
  background: rgba(255, 255, 255, 0.04);
  color: var(--color-text);
  border-color: transparent;
  border-left-color: transparent;
}

/* Active: purple left border glow */
.nav-item.active {
  background: rgba(108, 99, 255, 0.1);
  color: var(--color-text);
  border-color: rgba(108, 99, 255, 0.15);
  border-left-color: var(--color-primary);
}

.nav-item.active .nav-item__icon {
  color: var(--color-accent);
}

/* Course coming-soon items — more muted */
.nav-item.nav-item--muted {
  opacity: 0.55;
}

.nav-item.nav-item--muted:hover {
  opacity: 0.8;
}

.nav-item__icon {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(152, 152, 184, 0.6);
  transition: color var(--transition-fast);
}

.nav-item:hover .nav-item__icon { color: var(--color-text-secondary); }

.nav-item__label {
  transition: opacity var(--transition-base);
  overflow: hidden;
}

.sidebar.collapsed .nav-item__label {
  opacity: 0;
  width: 0;
  pointer-events: none;
}

/* ─── "Em breve" tag dentro do nav ─── */
.nav-item__soon {
  font-family: var(--font-mono);
  font-size: 8px;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: rgba(152, 152, 184, 0.5);
  border: 1px solid rgba(152, 152, 184, 0.2);
  border-radius: 3px;
  padding: 1px 5px;
  flex-shrink: 0;
  margin-left: auto;
  transition: opacity var(--transition-base);
}

.sidebar.collapsed .nav-item__soon { opacity: 0; }

/* Favorites empty state */
.nav-favorites-empty {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  font-size: 11px;
  color: var(--color-text-muted);
  font-style: italic;
  line-height: 1.4;
}
.nav-favorites-empty__icon {
  flex-shrink: 0;
  opacity: 0.5;
}
.sidebar.collapsed .nav-favorites-empty { display: none; }

/* Tooltip when collapsed */
.sidebar.collapsed .nav-item::after {
  content: attr(data-label);
  position: absolute;
  left: calc(var(--sidebar-collapsed) + var(--space-2));
  background: rgba(18, 18, 31, 0.98);
  color: var(--color-text);
  font-size: 12px;
  padding: 6px 12px;
  border-radius: var(--radius-md);
  border: 1px solid rgba(255,255,255,0.08);
  white-space: nowrap;
  pointer-events: none;
  opacity: 0;
  transform: translateX(-4px);
  transition: opacity var(--transition-fast), transform var(--transition-fast);
  z-index: calc(var(--z-sidebar) + 1);
  box-shadow: var(--shadow-md);
}

.sidebar.collapsed .nav-item:hover::after {
  opacity: 1;
  transform: translateX(0);
}

/* ─── Sidebar Footer ─── */
.sidebar__footer {
  padding: 12px 8px;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  flex-shrink: 0;
}

.sidebar__user {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 10px;
  border-radius: var(--radius-md);
  cursor: pointer;
  overflow: hidden;
  transition: background var(--transition-fast);
  border: 1px solid transparent;
}

.sidebar__user:hover {
  background: rgba(255, 255, 255, 0.04);
  border-color: rgba(255, 255, 255, 0.06);
}

.sidebar__avatar {
  width: 30px;
  height: 30px;
  flex-shrink: 0;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: var(--weight-bold);
  color: #fff;
  letter-spacing: 0.05em;
}

.sidebar__user-info {
  overflow: hidden;
  transition: opacity var(--transition-base);
}

.sidebar.collapsed .sidebar__user-info {
  opacity: 0;
  width: 0;
  pointer-events: none;
}

.sidebar__user-name {
  font-size: 12px;
  font-weight: var(--weight-semibold);
  color: var(--color-text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.sidebar__user-role {
  font-size: 10px;
  font-family: var(--font-mono);
  color: var(--color-accent);
  white-space: nowrap;
  letter-spacing: 0.04em;
}

/* ─── Header ─── */
.header {
  position: fixed;
  top: 0;
  right: 0;
  left: var(--sidebar-width);
  height: var(--header-height);
  background: rgba(10, 12, 22, 0.95);
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  backdrop-filter: blur(16px);
  z-index: var(--z-header);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-6);
  transition: left var(--transition-base),
              background-color var(--transition-slow),
              border-color var(--transition-slow);
}

.sidebar.collapsed ~ .main-wrapper .header {
  left: var(--sidebar-collapsed);
}

.header__left {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.header__title {
  font-size: var(--text-lg);
  font-weight: var(--weight-semibold);
  color: var(--color-text);
}

.header__right {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

/* ─── Main Wrapper ─── */
.main-wrapper {
  flex: 1;
  margin-left: var(--sidebar-width);
  transition: margin-left var(--transition-base);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.main-wrapper.sidebar-collapsed {
  margin-left: var(--sidebar-collapsed);
}

/* ─── Main Content ─── */
.main {
  flex: 1;
  padding: calc(var(--header-height) + var(--space-8)) var(--space-8) var(--space-8);
}

/* ─── Overlay (mobile sidebar) ─── */
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  z-index: calc(var(--z-sidebar) - 1);
  opacity: 0;
  transition: opacity var(--transition-base);
}

/* ─── Responsive ─── */
@media (max-width: 768px) {
  .sidebar {
    transform: translateX(-100%);
    width: var(--sidebar-width) !important;
    transition: transform var(--transition-base);
  }

  .sidebar.mobile-open {
    transform: translateX(0);
  }

  .sidebar-overlay {
    display: block;
  }

  .sidebar-overlay.visible {
    opacity: 1;
  }

  .main-wrapper {
    margin-left: 0 !important;
  }

  .header {
    left: 0 !important;
  }

  .main {
    padding: calc(var(--header-height) + var(--space-4)) var(--space-4) var(--space-4);
  }
}