/* ============================================
   БОКОВОЕ МЕНЮ CodeRift v2.1
   ============================================ */
:root {
  --sidebar-width: 260px;
  --sidebar-width-collapsed: 76px;
  --sidebar-bg: rgba(12, 16, 22, 0.96);
  --sidebar-border: rgba(72, 187, 255, 0.12);
  --sidebar-hover: rgba(72, 187, 255, 0.08);
  --sidebar-active-bg: linear-gradient(135deg, rgba(59, 130, 246, 0.22), rgba(168, 85, 247, 0.14));
  --sidebar-active-border: rgba(72, 187, 255, 0.35);
  --text-main: #eef2ff;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  --accent: #48bbff;
}

.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--sidebar-width);
  height: 100vh;
  background: var(--sidebar-bg);
  backdrop-filter: blur(16px) saturate(1.2);
  -webkit-backdrop-filter: blur(16px) saturate(1.2);
  border-right: 1px solid var(--sidebar-border);
  display: flex;
  flex-direction: column;
  z-index: 200;
  transition: width 0.3s cubic-bezier(0.16, 1, 0.3, 1), transform 0.25s ease;
  overflow: hidden;
}

/* ----- Бренд / логотип ----- */
.sidebar-brand {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  padding: 1.25rem 1rem 1rem;
  border-bottom: 1px solid var(--sidebar-border);
  flex-shrink: 0;
  min-height: 64px;
}

.sidebar-logo {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
  color: inherit;
  min-width: 0;
  flex-shrink: 0;
}

.sidebar-logo-icon {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}
.sidebar-logo-icon svg { width: 100%; height: 100%; display: block; }

.sidebar-logo-text {
  font-size: 1.45rem;
  font-weight: 800;
  letter-spacing: 0.3px;
  background: linear-gradient(135deg, #48bbff, #a855f7);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  white-space: nowrap;
  overflow: hidden;
}

.sidebar-collapse-btn {
  background: transparent;
  border: 1px solid var(--sidebar-border);
  color: var(--text-dim);
  width: 28px;
  height: 28px;
  min-width: 28px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s;
  flex-shrink: 0;
  padding: 0;
}
.sidebar-collapse-btn:hover {
  color: var(--accent);
  border-color: var(--sidebar-active-border);
  background: var(--sidebar-hover);
}
.sidebar-collapse-btn svg { width: 16px; height: 16px; transition: transform 0.3s; display: block; }
.sidebar.collapsed .sidebar-collapse-btn svg { transform: rotate(180deg); }

/* ----- Скроллируемая зона ----- */
.sidebar-scroll {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 1rem 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  scrollbar-width: thin;
  scrollbar-color: rgba(72,187,255,0.2) transparent;
}
.sidebar-scroll::-webkit-scrollbar { width: 6px; }
.sidebar-scroll::-webkit-scrollbar-thumb {
  background: rgba(72,187,255,0.2);
  border-radius: 10px;
}

/* ----- Секции ----- */
.sidebar-section { display: flex; flex-direction: column; gap: 0.4rem; }

.sidebar-section-title {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-dim);
  padding: 0 0.75rem;
  margin-bottom: 0.25rem;
  white-space: nowrap;
  overflow: hidden;
  transition: opacity 0.2s;
}

/* ----- Навигация ----- */
.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  list-style: none;
  padding: 0;
  margin: 0;
}

.sidebar-nav a {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.7rem 0.75rem;
  border-radius: 12px;
  text-decoration: none;
  color: #cbd5e6;
  font-weight: 500;
  font-size: 0.92rem;
  transition: all 0.18s ease;
  border: 1px solid transparent;
  position: relative;
  min-height: 44px;
  box-sizing: border-box;
}

.sidebar-nav a .nav-icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  transition: color 0.18s;
}
.sidebar-nav a .nav-icon svg { width: 100%; height: 100%; display: block; }

.sidebar-nav a .nav-label {
  white-space: nowrap;
  overflow: hidden;
  transition: opacity 0.2s;
}

.sidebar-nav a:hover {
  background: var(--sidebar-hover);
  color: var(--accent);
}
.sidebar-nav a:hover .nav-icon { color: var(--accent); }

.sidebar-nav a.active {
  background: var(--sidebar-active-bg);
  border-color: var(--sidebar-active-border);
  color: #fff;
  box-shadow: 0 4px 14px rgba(59, 130, 246, 0.12);
}
.sidebar-nav a.active .nav-icon { color: var(--accent); }

/* Бейдж прогресса курса */
.nav-progress-badge {
  margin-left: auto;
  font-size: 0.7rem;
  font-weight: 700;
  padding: 0.15rem 0.45rem;
  border-radius: 20px;
  background: rgba(34, 197, 94, 0.15);
  color: #4ade80;
  border: 1px solid rgba(34, 197, 94, 0.3);
  flex-shrink: 0;
}

/* Мини-прогресс под ссылкой курса */
.sidebar-mini-progress {
  height: 3px;
  background: #1e293b;
  border-radius: 4px;
  margin: 0.25rem 0.75rem 0;
  overflow: hidden;
}
.sidebar-mini-progress-fill {
  height: 100%;
  background: linear-gradient(90deg, #3b82f6, #a855f7);
  border-radius: 4px;
  transition: width 0.4s ease;
}

/* ----- Футер ----- */
.sidebar-footer {
  padding: 0.85rem 0.75rem 1rem;
  border-top: 1px solid var(--sidebar-border);
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  flex-shrink: 0;
}

.sidebar-user {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  padding: 0.4rem 0.4rem 0.4rem 0.5rem;
  border-radius: 12px;
  text-decoration: none;
  color: inherit;
  transition: background 0.18s;
}
.sidebar-user:hover { background: var(--sidebar-hover); }

.user-avatar-small {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: linear-gradient(135deg, #3b82f6, #a855f7);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.8rem;
  color: white;
  flex-shrink: 0;
  box-shadow: 0 0 0 2px rgba(72,187,255,0.15);
}

.user-meta { min-width: 0; display: flex; flex-direction: column; gap: 1px; }
.user-name {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-main);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.user-level {
  font-size: 0.72rem;
  color: var(--text-dim);
  white-space: nowrap;
}

.sidebar-xp-bar {
  height: 4px;
  background: #1e293b;
  border-radius: 4px;
  overflow: hidden;
  margin: 0 0.4rem;
}
.sidebar-xp-fill {
  height: 100%;
  background: linear-gradient(90deg, #3b82f6, #a855f7);
  border-radius: 4px;
  transition: width 0.4s ease;
}

.sidebar-logout,
.sidebar-login-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  width: 100%;
  padding: 0.6rem;
  border-radius: 12px;
  font-weight: 600;
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.18s;
  min-height: 40px;
  box-sizing: border-box;
}
.sidebar-logout {
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid rgba(239, 68, 68, 0.35);
  color: #f87171;
  font-family: inherit;
}
.sidebar-logout:hover {
  background: rgba(239, 68, 68, 0.2);
  border-color: #ef4444;
}
.sidebar-logout svg,
.sidebar-login-btn svg { width: 16px; height: 16px; flex-shrink: 0; display: block; }

.sidebar-login-btn {
  background: rgba(59, 130, 246, 0.12);
  border: 1px solid rgba(59, 130, 246, 0.4);
  color: #60a5fa;
  text-decoration: none;
}
.sidebar-login-btn:hover {
  background: rgba(59, 130, 246, 0.22);
  border-color: #3b82f6;
}

/* ----- Кнопка "Наверх" ----- */
.sidebar-scroll-top {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.5rem;
  margin: 0 0.75rem;
  background: transparent;
  border: 1px dashed rgba(72, 187, 255, 0.2);
  border-radius: 10px;
  color: var(--text-dim);
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
  opacity: 0;
  transform: translateY(8px);
  pointer-events: none;
  transition: all 0.25s;
  font-family: inherit;
  min-height: 36px;
  box-sizing: border-box;
}
.sidebar-scroll-top.visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}
.sidebar-scroll-top:hover {
  color: var(--accent);
  border-color: var(--sidebar-active-border);
  background: var(--sidebar-hover);
}
.sidebar-scroll-top svg { width: 14px; height: 14px; display: block; }

/* ============================================
   СВЁРНУТОЕ СОСТОЯНИЕ (десктоп)
   ============================================ */
.sidebar.collapsed { width: var(--sidebar-width-collapsed); }

/* Бренд: колонка, всё по центру */
.sidebar.collapsed .sidebar-brand {
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 0.5rem;
  padding: 0.9rem 0.5rem;
}
.sidebar.collapsed .sidebar-logo {
  justify-content: center;
  width: 100%;
}
.sidebar.collapsed .sidebar-collapse-btn {
  margin: 0 auto;
}

/* Скрываем текстовые элементы */
.sidebar.collapsed .sidebar-logo-text,
.sidebar.collapsed .sidebar-section-title,
.sidebar.collapsed .nav-label,
.sidebar.collapsed .nav-progress-badge,
.sidebar.collapsed .sidebar-mini-progress,
.sidebar.collapsed .user-meta,
.sidebar.collapsed .sidebar-xp-bar {
  opacity: 0;
  width: 0;
  height: 0;
  overflow: hidden;
  pointer-events: none;
  margin: 0;
  padding: 0;
}

/* Навигация: строго по центру, иконка фиксированного размера */
.sidebar.collapsed .sidebar-scroll {
  padding: 1rem 0.5rem;
}
.sidebar.collapsed .sidebar-nav a {
  justify-content: center;
  align-items: center;
  padding: 0.7rem 0;
  gap: 0;
}
.sidebar.collapsed .sidebar-nav a .nav-icon {
  width: 22px;
  height: 22px;
  margin: 0 auto;
}

/* Футер: колонка по центру */
.sidebar.collapsed .sidebar-footer {
  align-items: center;
  padding: 0.75rem 0.5rem 1rem;
}
.sidebar.collapsed .sidebar-user {
  justify-content: center;
  align-items: center;
  padding: 0.3rem;
  width: 100%;
  gap: 0;
}
.sidebar.collapsed .user-avatar-small {
  margin: 0 auto;
}

/* Кнопка «Выйти» / «Войти» — квадратная иконка по центру */
.sidebar.collapsed .sidebar-logout,
.sidebar.collapsed .sidebar-login-btn {
  width: 40px;
  min-width: 40px;
  height: 40px;
  min-height: 40px;
  padding: 0;
  border-radius: 10px;
  margin: 0 auto;
  gap: 0;
}
.sidebar.collapsed .sidebar-logout svg,
.sidebar.collapsed .sidebar-login-btn svg {
  width: 18px;
  height: 18px;
  margin: 0 auto;
}

/* Кнопка «Наверх» — круглая иконка по центру */
.sidebar.collapsed .sidebar-scroll-top {
  width: 36px;
  height: 36px;
  min-height: 36px;
  padding: 0;
  margin: 0 auto;
  border-radius: 50%;
  gap: 0;
}
.sidebar.collapsed .sidebar-scroll-top svg {
  margin: 0 auto;
}

/* Сдвиг контента */
body.has-sidebar {
  padding-left: var(--sidebar-width);
  min-height: 100vh;
  transition: padding-left 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}
body.has-sidebar.sidebar-collapsed { padding-left: var(--sidebar-width-collapsed); }

/* ============================================
   МОБИЛЬНЫЙ БУРГЕР
   ============================================ */
.sidebar-toggle {
  display: none;
  position: fixed;
  top: 1rem;
  left: 1rem;
  z-index: 300;
  background: rgba(17, 22, 31, 0.95);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(72, 187, 255, 0.3);
  width: 44px;
  height: 44px;
  border-radius: 12px;
  cursor: pointer;
  box-shadow: 0 4px 12px rgba(0,0,0,0.4);
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
  padding: 0;
}
.sidebar-toggle .hamburger-line {
  width: 18px;
  height: 2px;
  background: var(--accent);
  border-radius: 2px;
  transition: all 0.25s;
}
.sidebar-toggle:hover { background: rgba(72, 187, 255, 0.12); }

.sidebar-backdrop {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(2px);
  z-index: 150;
}

/* ============================================
   АДАПТИВ
   ============================================ */
@media (max-width: 900px) {
  .sidebar {
    transform: translateX(-100%);
    width: var(--sidebar-width);
    box-shadow: 20px 0 60px rgba(0,0,0,0.5);
  }
  .sidebar.open { transform: translateX(0); }

  /* На мобильном «свёрнутый» режим не имеет смысла — показываем полное меню */
  .sidebar.collapsed { width: var(--sidebar-width); }
  .sidebar.collapsed .sidebar-brand {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    padding: 1.25rem 1rem 1rem;
    gap: 0.5rem;
  }
  .sidebar.collapsed .sidebar-logo { justify-content: flex-start; width: auto; }
  .sidebar.collapsed .sidebar-logo-text,
  .sidebar.collapsed .sidebar-section-title,
  .sidebar.collapsed .nav-label,
  .sidebar.collapsed .nav-progress-badge,
  .sidebar.collapsed .sidebar-mini-progress,
  .sidebar.collapsed .user-meta,
  .sidebar.collapsed .sidebar-xp-bar {
    opacity: 1;
    width: auto;
    height: auto;
    pointer-events: auto;
    margin: revert;
    padding: revert;
  }
  .sidebar.collapsed .sidebar-scroll { padding: 1rem 0.75rem; }
  .sidebar.collapsed .sidebar-nav a {
    justify-content: flex-start;
    padding: 0.7rem 0.75rem;
    gap: 0.75rem;
  }
  .sidebar.collapsed .sidebar-nav a .nav-icon {
    width: 20px;
    height: 20px;
    margin: 0;
  }
  .sidebar.collapsed .sidebar-footer {
    align-items: stretch;
    padding: 0.85rem 0.75rem 1rem;
  }
  .sidebar.collapsed .sidebar-user {
    justify-content: flex-start;
    padding: 0.4rem 0.4rem 0.4rem 0.5rem;
    gap: 0.7rem;
  }
  .sidebar.collapsed .user-avatar-small { margin: 0; }
  .sidebar.collapsed .sidebar-logout,
  .sidebar.collapsed .sidebar-login-btn {
    width: 100%;
    min-width: 0;
    height: auto;
    min-height: 40px;
    padding: 0.6rem;
    border-radius: 12px;
    gap: 0.6rem;
  }
  .sidebar.collapsed .sidebar-scroll-top {
    width: auto;
    height: auto;
    min-height: 36px;
    padding: 0.5rem;
    margin: 0 0.75rem;
    border-radius: 10px;
    gap: 0.5rem;
  }
  .sidebar-collapse-btn { display: none; }

  body.has-sidebar,
  body.has-sidebar.sidebar-collapsed {
    padding-left: 0;
    padding-top: 0;
  }
  .sidebar-toggle { display: flex; }
  .sidebar.open ~ .sidebar-backdrop,
  .sidebar-backdrop.show { display: block; }
}

/* Очень узкие экраны — уменьшаем отступы */
@media (max-width: 380px) {
  :root { --sidebar-width: 240px; }
  .sidebar-brand { padding: 1rem 0.75rem 0.85rem; }
  .sidebar-scroll { padding: 0.75rem 0.5rem; }
  .sidebar-footer { padding: 0.75rem 0.5rem 0.85rem; }
  .sidebar-nav a { padding: 0.6rem 0.65rem; font-size: 0.88rem; }
}

/* Уважение к prefers-reduced-motion */
@media (prefers-reduced-motion: reduce) {
  .sidebar, body.has-sidebar, .sidebar-collapse-btn svg,
  .sidebar-scroll-top, .sidebar-xp-fill, .sidebar-mini-progress-fill {
    transition: none !important;
  }
}