/**
 * Course Sidebar Navigation Styles
 * Sidebar with accordion modules, search, and mobile drawer
 * Scoped to .course-sidebar and related classes
 */

/* ═══════════════════════════════════════
   CSS VARIABLES (sidebar-specific)
   ═══════════════════════════════════════ */
:root {
  --sidebar-width: 280px;
}

/* ═══════════════════════════════════════
   LAYOUT: sidebar + content wrapper
   ═══════════════════════════════════════ */

/* When sidebar is present, offset the main content */
html:has(.course-sidebar) .lesson-page {
  max-width: none;
  padding-left: 0;
  padding-right: 0;
}

html:has(.course-sidebar) main {
  margin-left: var(--sidebar-width);
}

/* Progress header spans full width above content (not sidebar) */
html:has(.course-sidebar) .lesson-progress-header {
  position: sticky;
  top: var(--header-height, 73px);
  z-index: calc(var(--z-sidebar, 300) + 5);
  background: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  padding: var(--spacing-md) var(--spacing-3xl, 64px);
  border-bottom: 1px solid var(--color-border-light);
}

/* Bottom nav offset for sidebar */
html:has(.course-sidebar) .screen-nav-premium {
  left: var(--sidebar-width);
}

/* ═══════════════════════════════════════
   SIDEBAR CONTAINER
   ═══════════════════════════════════════ */
.course-sidebar {
  position: fixed;
  top: var(--header-height, 73px);
  left: 0;
  width: var(--sidebar-width);
  height: calc(100dvh - var(--header-height, 73px));
  background: rgba(248, 250, 252, 0.98);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-right: 1px solid rgba(75, 96, 110, 0.10);
  box-shadow: 2px 0 12px rgba(75, 96, 110, 0.06);
  z-index: var(--z-sidebar, 300);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.sidebar-content {
  flex: 1;
  overflow-y: auto;
  padding: var(--spacing-md) var(--spacing-md) var(--spacing-xl);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
  scroll-behavior: smooth;
  -webkit-overflow-scrolling: touch;
}

/* Custom scrollbar */
.sidebar-content::-webkit-scrollbar {
  width: 6px;
}
.sidebar-content::-webkit-scrollbar-track {
  background: transparent;
}
.sidebar-content::-webkit-scrollbar-thumb {
  background: rgba(75, 96, 110, 0.15);
  border-radius: 3px;
}
.sidebar-content::-webkit-scrollbar-thumb:hover {
  background: rgba(75, 96, 110, 0.25);
}

/* ═══════════════════════════════════════
   SIDEBAR HEADER
   ═══════════════════════════════════════ */
.sidebar-header {
  position: sticky;
  top: 0;
  background: rgba(248, 250, 252, 0.98);
  backdrop-filter: blur(10px);
  padding: 12px 16px 8px;
  margin: calc(-1 * var(--spacing-md));
  margin-bottom: var(--spacing-md);
  border-bottom: 1px solid rgba(75, 96, 110, 0.08);
  z-index: 10;
}

.sidebar-header__course {
  font-family: var(--font-family-heading);
  font-size: 14px;
  font-weight: 600;
  color: var(--color-text);
  line-height: 1.3;
  letter-spacing: -0.01em;
}

.sidebar-header__progress {
  font-family: var(--font-family);
  font-size: 12px;
  color: var(--color-text-muted);
  margin-top: 4px;
  font-weight: var(--font-weight-normal);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.01em;
}

/* ═══════════════════════════════════════
   SEARCH
   ═══════════════════════════════════════ */
.sidebar-search {
  position: relative;
  padding: 0 16px;
  margin-bottom: 8px;
}

.sidebar-search__icon {
  position: absolute;
  left: 28px;
  top: 50%;
  transform: translateY(-50%);
  width: 14px;
  height: 14px;
  color: var(--color-text-muted);
  pointer-events: none;
}

.sidebar-search__input {
  width: 100%;
  height: 36px;
  padding: 0 12px 0 36px;
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.8);
  font-family: var(--font-family);
  font-size: 13px;
  color: var(--color-text);
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.sidebar-search__input::placeholder {
  color: var(--color-text-muted);
}

.sidebar-search__input:focus {
  border-color: var(--color-main);
  box-shadow: 0 0 0 3px rgba(75, 96, 110, 0.08);
}

.sidebar-search__results {
  position: absolute;
  left: 16px;
  right: 16px;
  top: 100%;
  margin-top: 4px;
  background: #fff;
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  max-height: 300px;
  overflow-y: auto;
  z-index: 20;
  display: none;
}

.sidebar-search__results.visible {
  display: block;
}

.sidebar-search__result {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 8px 12px;
  cursor: pointer;
  transition: background var(--transition-fast);
  text-decoration: none;
  color: inherit;
}

.sidebar-search__result:hover {
  background: var(--color-surface-hover);
  text-decoration: none;
  color: inherit;
}

.sidebar-search__result--locked {
  opacity: 0.5;
}

.sidebar-search__result-name {
  font-size: 13px;
  font-weight: var(--font-weight-medium);
  color: var(--color-text);
}

.sidebar-search__result-name mark {
  background: var(--color-selection);
  color: inherit;
  border-radius: 2px;
  padding: 0 1px;
}

.sidebar-search__result-module {
  font-size: 11px;
  color: var(--color-text-muted);
}

.sidebar-search__empty {
  padding: 12px;
  font-size: 13px;
  color: var(--color-text-muted);
  text-align: center;
}

/* ═══════════════════════════════════════
   MODULES ACCORDION
   ═══════════════════════════════════════ */
.sidebar-modules {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.module {
  border-radius: var(--radius-md);
  overflow: hidden;
}

.module__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-sm) var(--spacing-md);
  cursor: pointer;
  list-style: none;
  background: transparent;
  border-radius: var(--radius-md);
  transition: background 0.3s cubic-bezier(0.25, 0.1, 0.25, 1);
  min-height: 44px;
}

.module__summary::-webkit-details-marker {
  display: none;
}

.module__summary:hover {
  background: rgba(75, 96, 110, 0.05);
}

.module__header {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-2xs);
}

.module__title {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: -0.01em;
  text-transform: none;
  color: var(--color-text);
  transition: color var(--transition-fast);
  font-family: var(--font-family);
}

.module__icon {
  font-size: 11px;
  color: var(--color-text-muted);
  opacity: 0.7;
  transition: transform var(--transition-normal);
}

.module[open] .module__icon {
  transform: rotate(180deg);
}

/* Mini progress bar */
.module__progress-bar {
  height: 3px;
  background: rgba(75, 96, 110, 0.08);
  border-radius: 2px;
  margin: 0 var(--spacing-md);
  margin-top: 4px;
  overflow: hidden;
}

.module__progress-bar-fill {
  height: 100%;
  background: var(--color-success);
  border-radius: 2px;
  transition: width var(--transition-slow);
}

/* Lesson list animation */
.lesson-list {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.35s cubic-bezier(0.32, 0.72, 0, 1);
}

.lesson-list > div {
  overflow: hidden;
  opacity: 0;
  transition: opacity 0.3s ease 0.1s;
}

.module[open] .lesson-list {
  grid-template-rows: 1fr;
}

.module[open] .lesson-list > div {
  opacity: 1;
}

.lessons {
  display: flex;
  flex-direction: column;
  padding: var(--spacing-xs);
  gap: var(--spacing-2xs);
}

/* ═══════════════════════════════════════
   LESSON ITEMS
   ═══════════════════════════════════════ */
.sidebar-lesson {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-md);
  min-height: 44px;
  cursor: pointer;
  background: transparent;
  border-radius: var(--radius-md);
  transition: background 0.3s cubic-bezier(0.25, 0.1, 0.25, 1);
  text-decoration: none;
  color: inherit;
}

.sidebar-lesson:hover {
  background: rgba(75, 96, 110, 0.04);
  text-decoration: none;
  color: inherit;
}

.sidebar-lesson:focus-visible {
  outline: 2px solid var(--color-main);
  outline-offset: 2px;
}

.sidebar-lesson__icon {
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 13px;
}

.sidebar-lesson__icon--completed {
  color: var(--color-success);
  opacity: 0.7;
}

.sidebar-lesson__icon--current {
  color: var(--color-current, var(--color-text));
  position: relative;
}

.sidebar-lesson__icon--current::after {
  content: '';
  position: absolute;
  width: 8px;
  height: 8px;
  background: var(--color-current, var(--color-text));
  border-radius: 50%;
}

.sidebar-lesson__icon--available {
  color: var(--color-text-muted);
  opacity: 0.7;
}

.sidebar-lesson__icon--locked {
  color: var(--color-text-muted);
  opacity: 0.35;
}

.sidebar-lesson__name {
  font-size: 14px;
  font-weight: var(--font-weight-medium);
  color: var(--color-text);
  flex: 1;
  transition: color var(--transition-fast);
  letter-spacing: -0.01em;
}

/* Completed lesson */
.sidebar-lesson--completed .sidebar-lesson__name {
  opacity: 0.7;
  font-weight: var(--font-weight-normal);
}

/* Current lesson */
.sidebar-lesson--current .sidebar-lesson__name {
  font-weight: var(--font-weight-semibold);
  color: var(--color-text);
}

/* Available lesson */
.sidebar-lesson--available .sidebar-lesson__name {
  opacity: 0.85;
}

/* Locked lesson */
.sidebar-lesson--locked {
  cursor: default;
}

.sidebar-lesson--locked .sidebar-lesson__name {
  opacity: 0.35;
}

/* ═══════════════════════════════════════
   MODULE STATES
   ═══════════════════════════════════════ */

/* Not started module */
.module--not-started .module__title {
  color: rgba(75, 96, 110, 0.50);
}

.module--not-started .lesson-preview {
  list-style: none;
  padding: var(--spacing-xs) var(--spacing-md) var(--spacing-sm);
}

.module--not-started .lesson-preview li {
  font-size: 13px;
  color: rgba(75, 96, 110, 0.45);
  cursor: default;
  padding: 6px var(--spacing-sm);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.module--not-started .lesson-preview li::before {
  content: '○';
  font-size: 11px;
  color: var(--color-text-muted);
  opacity: 0.5;
}

/* Locked module */
.module--locked .module__summary {
  cursor: default;
}

.module--locked .module__title {
  color: var(--color-text-muted);
  font-weight: var(--font-weight-medium);
  letter-spacing: 0.06em;
  opacity: 0.7;
}

.module--locked .module__icon {
  opacity: 0.35;
}

/* ═══════════════════════════════════════
   HAMBURGER BUTTON (mobile)
   ═══════════════════════════════════════ */
.sidebar-hamburger-btn {
  display: none;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background: transparent;
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
  cursor: pointer;
  color: var(--color-text);
  transition: all var(--transition-fast);
}

.sidebar-hamburger-btn:hover {
  background: var(--color-surface-hover);
  border-color: var(--color-border);
}

.sidebar-hamburger-btn:focus-visible {
  outline: 2px solid var(--color-main);
  outline-offset: 2px;
}

.sidebar-hamburger-btn svg {
  width: 20px;
  height: 20px;
}

/* Drawer backdrop (mobile) */
.sidebar-drawer-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  z-index: 999;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.3s ease, visibility 0.3s ease;
  display: none;
}

.sidebar-drawer-backdrop.active {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

/* ═══════════════════════════════════════
   RESPONSIVE
   ═══════════════════════════════════════ */
@media (max-width: 1023px) {
  .course-sidebar {
    transform: translateX(-100%);
    transition: transform 0.35s cubic-bezier(0.32, 0.72, 0, 1);
    width: 85vw;
    max-width: 320px;
    box-shadow: 8px 0 32px rgba(75, 96, 110, 0.12);
  }

  .course-sidebar.active {
    transform: translateX(0);
    z-index: 1000;
  }

  html:has(.course-sidebar) main {
    margin-left: 0;
  }

  .sidebar-hamburger-btn {
    display: inline-flex;
  }

  .sidebar-drawer-backdrop {
    display: block;
  }

  html:has(.course-sidebar) .screen-nav-premium {
    left: 0;
  }

  html:has(.course-sidebar) .lesson-progress-header {
    padding-left: var(--spacing-lg);
    padding-right: var(--spacing-lg);
  }
}

@media (max-width: 768px) {
  .course-sidebar {
    top: 57px;
    height: calc(100dvh - 57px);
    max-width: 300px;
  }

  .lessons {
    padding: var(--spacing-xs);
  }

  .sidebar-lesson {
    padding: 10px var(--spacing-sm);
    min-height: 40px;
  }

  .sidebar-lesson__name {
    font-size: 13px;
  }
}

/* ═══════════════════════════════════════
   CLOSE BUTTON (mobile drawer)
   ═══════════════════════════════════════ */
.sidebar-close-btn {
  display: none;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: transparent;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  color: var(--color-text-muted);
  font-size: 18px;
  line-height: 1;
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.sidebar-close-btn:hover {
  background: rgba(75, 96, 110, 0.08);
  color: var(--color-text);
}

@media (max-width: 1023px) {
  .sidebar-close-btn {
    display: inline-flex;
  }

  .sidebar-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: var(--spacing-sm);
  }
}

/* ═══════════════════════════════════════
   FOCUS & ACCESSIBILITY
   ═══════════════════════════════════════ */
.module__summary:focus-visible {
  outline: 2px solid var(--color-main);
  outline-offset: 2px;
}

/* ═══════════════════════════════════════
   REDUCED MOTION
   ═══════════════════════════════════════ */
@media (prefers-reduced-motion: reduce) {
  .course-sidebar {
    transition: none;
  }

  .sidebar-lesson__icon--current::after {
    animation: none;
  }

  .lesson-list,
  .lesson-list > div {
    transition: none;
  }
}