/* ============================================================
   InstructorNav.module.css
   Premium minimalist topbar + sidebar navigation for Instructors.
   ============================================================ */

/* --- Custom Properties --- */
:root {
  --nav_mod_topbar_h: 70px;
  --nav_mod_sidebar_w: 260px;
  --nav_mod_sidebar_cw: 72px;
  --nav_mod_white: #ffffff;
  --nav_mod_bg: #f8fafc;
  --nav_mod_text: #334155;
  --nav_mod_heading: #0f172a;
  --nav_mod_muted: #94a3b8;
  --nav_mod_muted_strong: #64748b;
  --nav_mod_border: rgba(15, 23, 42, 0.06);
  --nav_mod_border_strong: rgba(15, 23, 42, 0.10);
  
  /* Brand Accent: Royal Indigo (Instructor theme matching) */
  --nav_mod_accent: hsl(256, 100%, 56%);
  --nav_mod_accent_soft: hsla(256, 100%, 56%, 0.06);
  --nav_mod_accent_border: hsla(256, 100%, 56%, 0.15);
  
  --nav_mod_shadow_xs: 0 1px 2px rgba(15, 23, 42, 0.04);
  --nav_mod_shadow_sm: 0 4px 12px rgba(15, 23, 42, 0.05);
  --nav_mod_shadow_md: 0 8px 24px rgba(15, 23, 42, 0.08);
  --nav_mod_shadow_lg: 0 16px 40px rgba(15, 23, 42, 0.12);
  --nav_mod_radius: 10px;
  --nav_mod_radius_lg: 14px;
  --nav_mod_transition: 0.22s cubic-bezier(0.4, 0, 0.2, 1);
}

/* --- Layout overrides for Instructor Shell --- */
body.instructor-ui {
  --sv-topbar-height: var(--nav_mod_topbar_h);
  --sv-sidebar-width: var(--nav_mod_sidebar_w);
  --sv-sidebar-collapsed-width: var(--nav_mod_sidebar_cw);
}

body.instructor-ui .app-main {
  margin-left: var(--nav_mod_sidebar_w) !important;
  margin-top: var(--nav_mod_topbar_h) !important;
  min-height: calc(100vh - var(--nav_mod_topbar_h)) !important;
  transition: margin-left var(--nav_mod_transition) !important;
}

body.instructor-ui.ins-shell-collapsed .app-main {
  margin-left: var(--nav_mod_sidebar_cw) !important;
}

/* ============================================================
   1. TOP NAVIGATION BAR
   ============================================================ */

.nav_mod_topbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav_mod_topbar_h);
  z-index: 120;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 0 24px 0 16px;
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(16px) saturate(180%);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  border-bottom: 1px solid var(--nav_mod_border);
  transition: background var(--nav_mod_transition), border-color var(--nav_mod_transition);
}

.nav_mod_top_left,
.nav_mod_top_right {
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav_mod_top_left {
  flex: 1 1 auto;
  min-width: 0;
}

.nav_mod_top_right {
  flex: 0 0 auto;
  margin-left: auto;
}

/* --- Hamburger Toggle --- */
.nav_mod_toggle {
  width: 36px;
  height: 36px;
  display: inline-grid;
  place-items: center;
  border: 1px solid var(--nav_mod_border);
  border-radius: var(--nav_mod_radius);
  background: var(--nav_mod_white);
  color: var(--nav_mod_heading);
  cursor: pointer;
  transition: all var(--nav_mod_transition);
  font-size: 0.88rem;
}

.nav_mod_toggle:hover {
  border-color: var(--nav_mod_accent_border);
  background: var(--nav_mod_accent_soft);
  color: var(--nav_mod_accent);
  box-shadow: var(--nav_mod_shadow_sm);
}

/* --- Brand Logo --- */
.nav_mod_brand {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  text-decoration: none;
  color: var(--nav_mod_heading);
}

.nav_mod_brand_main {
  font-size: 0.92rem;
  font-weight: 800;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  line-height: 1;
  color: var(--nav_mod_heading);
}

.nav_mod_brand_sub {
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--nav_mod_muted);
  line-height: 1;
}

/* --- Page Title Divider --- */
.nav_mod_page_title {
  display: grid;
  min-width: 0;
  padding-left: 16px;
  border-left: 1px solid var(--nav_mod_border_strong);
}

.nav_mod_page_title h1 {
  margin: 0;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--nav_mod_muted_strong);
  letter-spacing: -0.01em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* --- Icon Buttons --- */
.nav_mod_icon_btn {
  position: relative;
  width: 38px;
  height: 38px;
  padding: 0;
  display: inline-grid;
  place-items: center;
  border: 1px solid var(--nav_mod_border);
  border-radius: var(--nav_mod_radius);
  background: var(--nav_mod_white);
  color: var(--nav_mod_muted_strong);
  cursor: pointer;
  transition: all var(--nav_mod_transition);
  font-size: 0.92rem;
}

.nav_mod_icon_btn:hover {
  border-color: var(--nav_mod_accent_border);
  background: var(--nav_mod_accent_soft);
  color: var(--nav_mod_accent);
  box-shadow: var(--nav_mod_shadow_sm);
  transform: translateY(-1px);
}

/* --- Theme Toggle --- */
.nav_mod_theme_toggle {
  position: relative;
  width: 38px;
  height: 38px;
  min-height: 38px;
  padding: 0;
  display: inline-grid;
  place-items: center;
  border: 1px solid var(--nav_mod_border);
  border-radius: var(--nav_mod_radius);
  background: var(--nav_mod_white);
  color: var(--nav_mod_muted_strong);
  cursor: pointer;
  transition: all var(--nav_mod_transition);
  font-size: 0.92rem;
  box-shadow: none;
}

.nav_mod_theme_toggle:hover {
  border-color: var(--nav_mod_accent_border);
  background: var(--nav_mod_accent_soft);
  color: var(--nav_mod_accent);
  box-shadow: var(--nav_mod_shadow_sm);
  transform: translateY(-1px);
}

.nav_mod_theme_toggle .theme-toggle-label {
  display: none;
}

.nav_mod_badge {
  position: absolute;
  top: -3px;
  right: -3px;
  min-width: 18px;
  height: 18px;
  padding: 0 5px;
  border-radius: 999px;
  background: linear-gradient(135deg, #ef4444, #f97316);
  color: #ffffff;
  font-size: 0.62rem;
  font-weight: 800;
  line-height: 18px;
  text-align: center;
  box-shadow: 0 2px 8px rgba(239, 68, 68, 0.3);
}

/* --- Profile Dropdown --- */
.nav_mod_profile_dropdown {
  position: relative;
  display: inline-flex;
}

.nav_mod_profile_trigger {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 4px 12px 4px 4px;
  min-height: 42px;
  border: 1px solid var(--nav_mod_border);
  border-radius: 22px;
  background: var(--nav_mod_white);
  color: var(--nav_mod_heading);
  cursor: pointer;
  transition: all var(--nav_mod_transition);
  font-size: 0.86rem;
  font-weight: 600;
  box-shadow: none;
}

.nav_mod_profile_trigger:hover {
  border-color: var(--nav_mod_border_strong);
  box-shadow: var(--nav_mod_shadow_sm);
}

.nav_mod_profile_name {
  font-size: 0.84rem;
  font-weight: 700;
  color: var(--nav_mod_heading);
  max-width: 120px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.nav_mod_profile_copy {
  display: grid;
  min-width: 0;
}

.nav_mod_avatar {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, #e0e7ff, #c7d2fe);
  overflow: hidden;
  flex-shrink: 0;
}

.nav_mod_avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.nav_mod_avatar_fallback {
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  color: var(--nav_mod_accent);
}

.nav_mod_profile_trigger i.fa-angle-down {
  font-size: 0.72rem;
  color: var(--nav_mod_muted);
  transition: transform var(--nav_mod_transition);
}

.nav_mod_profile_menu {
  position: absolute;
  right: 0;
  top: calc(100% + 10px);
  width: min(220px, 72vw);
  border: 1px solid var(--nav_mod_border);
  border-radius: var(--nav_mod_radius_lg);
  background: var(--nav_mod_white);
  box-shadow: var(--nav_mod_shadow_lg);
  padding: 6px;
  display: none;
  z-index: 140;
  overflow: hidden;
}

.nav_mod_profile_menu.open {
  display: block;
  animation: nav_mod_fadeIn 0.18s ease;
}

.nav_mod_profile_menu a {
  display: flex;
  align-items: center;
  gap: 10px;
  min-height: 40px;
  padding: 0 12px;
  border-radius: 8px;
  color: var(--nav_mod_text);
  font-size: 0.84rem;
  font-weight: 600;
  text-decoration: none;
  transition: all var(--nav_mod_transition);
}

.nav_mod_profile_menu a i {
  width: 16px;
  text-align: center;
  font-size: 0.82rem;
  color: var(--nav_mod_muted_strong);
}

.nav_mod_profile_menu a:hover {
  background: var(--nav_mod_accent_soft);
  color: var(--nav_mod_accent);
}

.nav_mod_profile_menu a:hover i {
  color: var(--nav_mod_accent);
}

.nav_mod_profile_menu a.nav_mod_logout_link {
  color: #ef4444;
  margin-top: 2px;
  border-top: 1px solid var(--nav_mod_border);
  border-radius: 0 0 8px 8px;
  padding-top: 2px;
}

.nav_mod_profile_menu a.nav_mod_logout_link i {
  color: #ef4444;
}

.nav_mod_profile_menu a.nav_mod_logout_link:hover {
  background: rgba(239, 68, 68, 0.06);
}

/* --- Notification Popover --- */
.nav_mod_popover {
  position: relative;
}

.nav_mod_popover_panel {
  position: absolute;
  right: 0;
  top: calc(100% + 10px);
  width: min(320px, 80vw);
  border: 1px solid var(--nav_mod_border);
  border-radius: var(--nav_mod_radius_lg);
  background: var(--nav_mod_white);
  box-shadow: var(--nav_mod_shadow_lg);
  padding: 0;
  display: none;
  z-index: 140;
  overflow: hidden;
}

.nav_mod_popover_panel.open {
  display: block;
  animation: nav_mod_fadeIn 0.18s ease;
}

.nav_mod_popover_head {
  display: grid;
  gap: 2px;
  padding: 16px 18px 12px;
  border-bottom: 1px solid var(--nav_mod_border);
}

.nav_mod_popover_head strong {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--nav_mod_heading);
}

.nav_mod_popover_head small {
  font-size: 0.78rem;
  color: var(--nav_mod_muted);
}

.nav_mod_popover_body {
  padding: 14px 18px 16px;
}

.nav_mod_popover_body p {
  margin: 0;
  font-size: 0.82rem;
  color: var(--nav_mod_muted);
  line-height: 1.6;
}

/* ============================================================
   2. SIDEBAR NAVIGATION
   ============================================================ */

.nav_mod_sidebar {
  position: fixed;
  top: var(--nav_mod_topbar_h);
  left: 0;
  width: var(--nav_mod_sidebar_w);
  height: calc(100vh - var(--nav_mod_topbar_h));
  padding: 20px 12px 20px;
  background: var(--nav_mod_white);
  border-right: 1px solid var(--nav_mod_border);
  overflow-y: auto;
  overflow-x: hidden;
  z-index: 110;
  transition: width var(--nav_mod_transition), transform var(--nav_mod_transition),
              box-shadow var(--nav_mod_transition), padding var(--nav_mod_transition);
}

.nav_mod_sidebar::-webkit-scrollbar {
  width: 3px;
}
.nav_mod_sidebar::-webkit-scrollbar-track {
  background: transparent;
}
.nav_mod_sidebar::-webkit-scrollbar-thumb {
  background: rgba(148, 163, 184, 0.25);
  border-radius: 999px;
}

.nav_mod_sidebar_shell {
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-height: 100%;
  padding-bottom: 24px;
}

.nav_mod_nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
  flex: 1 1 auto;
  min-height: 100%;
}

.nav_mod_spacer {
  flex: 1 1 auto;
  min-height: 24px;
}

.nav_mod_section_label {
  display: block;
  padding: 18px 14px 6px;
  font-size: 0.64rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--nav_mod_muted);
  transition: opacity var(--nav_mod_transition), max-height var(--nav_mod_transition),
              padding var(--nav_mod_transition);
}

.nav_mod_divider {
  margin: 6px 12px;
  border: 0;
  border-top: 1px solid var(--nav_mod_border);
}

.nav_mod_link {
  position: relative;
  display: grid;
  grid-template-columns: 20px minmax(0, 1fr);
  align-items: center;
  gap: 12px;
  min-height: 40px;
  padding: 0 14px;
  border: none;
  border-radius: 8px;
  color: var(--nav_mod_muted_strong);
  font-size: 0.84rem;
  font-weight: 600;
  text-decoration: none;
  transition: all var(--nav_mod_transition);
}

.nav_mod_link i {
  width: 20px;
  text-align: center;
  font-size: 0.92rem;
  transition: color var(--nav_mod_transition);
}

.nav_mod_link:hover {
  background: var(--nav_mod_bg);
  color: var(--nav_mod_heading);
}

.nav_mod_link:hover i {
  color: var(--nav_mod_accent);
}

.nav_mod_link.active {
  background: #e0e7ff;
  color: #4f46e5;
  font-weight: 700;
}

.nav_mod_link.active i {
  color: #4f46e5;
}

/* Pseudo element removed for cleaner Indigo look */

.nav_mod_link_danger {
  color: #f87171;
}

.nav_mod_link_danger:hover {
  background: rgba(239, 68, 68, 0.06);
  color: #ef4444;
}

.nav_mod_link_danger:hover i {
  color: #ef4444;
}

.nav_mod_label {
  display: block;
  min-width: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: opacity var(--nav_mod_transition), transform var(--nav_mod_transition),
              max-width 0.2s ease;
}

/* ============================================================
   3. COLLAPSED STATE (Instructor overrides)
   ============================================================ */

body.ins-shell-collapsed .nav_mod_sidebar {
  width: var(--nav_mod_sidebar_cw);
  padding-inline: 8px;
}

body.ins-shell-collapsed .nav_mod_label {
  max-width: 0;
  opacity: 0;
  transform: translateX(-6px);
  pointer-events: none;
  overflow: hidden;
}

body.ins-shell-collapsed .nav_mod_section_label {
  opacity: 0;
  max-height: 0;
  padding: 0;
  margin: 0;
  overflow: hidden;
  pointer-events: none;
}

body.ins-shell-collapsed .nav_mod_divider {
  margin: 4px 4px;
}

body.ins-shell-collapsed .nav_mod_link {
  grid-template-columns: 1fr;
  gap: 0;
  justify-items: center;
  padding-inline: 0;
  border-radius: var(--nav_mod_radius);
}

body.ins-shell-collapsed .nav_mod_link i {
  width: auto;
}

body.ins-shell-collapsed .nav_mod_link::after {
  position: absolute;
  left: calc(100% + 10px);
  top: 50%;
  transform: translateY(-50%);
  padding: 6px 10px;
  border-radius: 6px;
  background: var(--nav_mod_heading);
  color: #ffffff;
  font-size: 0.76rem;
  font-weight: 600;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  box-shadow: var(--nav_mod_shadow_md);
  transition: opacity 0.15s ease, transform 0.15s ease;
  z-index: 160;
}

body.ins-shell-collapsed .nav_mod_link:hover::after {
  opacity: 1;
  transform: translate(4px, -50%);
}

body.ins-shell-collapsed .nav_mod_link[title]:hover::after {
  content: attr(title);
}

/* body.ins-shell-collapsed .nav_mod_link.active::before removed */

/* ============================================================
   4. MOBILE RESPONSIVE
   ============================================================ */

@media (max-width: 1100px) {
  .nav_mod_sidebar {
    width: var(--nav_mod_sidebar_w);
    transform: translateX(-100%);
    box-shadow: none;
  }

  body.instructor-ui .app-main {
    margin-left: 0 !important;
  }

  body.instructor-ui.ins-shell-collapsed .nav_mod_label {
    max-width: none;
    opacity: 1;
    transform: none;
    pointer-events: auto;
  }

  body.instructor-ui.ins-shell-collapsed .nav_mod_section_label {
    opacity: 1;
    max-height: none;
    padding: 18px 14px 6px;
  }

  body.instructor-ui.ins-shell-collapsed .nav_mod_link {
    grid-template-columns: 20px minmax(0, 1fr);
    gap: 12px;
    justify-items: initial;
    padding-inline: 14px;
  }

  body.instructor-ui.ins-shell-collapsed .nav_mod_sidebar {
    width: var(--nav_mod_sidebar_w);
    padding-inline: 12px;
  }

  body.instructor-ui.ins-mobile-nav-open .nav_mod_sidebar {
    transform: translateX(0);
    box-shadow: var(--nav_mod_shadow_lg);
  }
}

@media (max-width: 820px) {
  .nav_mod_topbar {
    padding-inline: 14px;
    gap: 10px;
  }
  .nav_mod_page_title {
    padding-left: 10px;
  }
}

@media (max-width: 760px) {
  .nav_mod_topbar {
    padding-inline: 12px;
    height: 60px;
  }

  :root {
    --nav_mod_topbar_h: 60px;
  }

  .nav_mod_brand_sub {
    display: none;
  }

  .nav_mod_page_title h1 {
    font-size: 0.82rem;
  }

  .nav_mod_profile_name {
    display: none;
  }

  .nav_mod_profile_trigger {
    padding: 4px;
    border-radius: 50%;
    gap: 0;
  }

  .nav_mod_profile_trigger i.fa-angle-down {
    display: none;
  }

  .nav_mod_sidebar {
    padding: 16px 12px;
  }
}

/* ============================================================
   5. ANIMATIONS
   ============================================================ */

@keyframes nav_mod_fadeIn {
  from {
    opacity: 0;
    transform: translateY(-6px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ============================================================
   6. DARK MODE OVERRIDES
   ============================================================ */

html[data-theme='dark'] .nav_mod_topbar {
  background: rgba(15, 23, 42, 0.92);
  border-bottom-color: rgba(148, 163, 184, 0.1);
}

html[data-theme='dark'] .nav_mod_toggle,
html[data-theme='dark'] .nav_mod_icon_btn,
html[data-theme='dark'] .nav_mod_theme_toggle {
  background: rgba(30, 41, 59, 0.8);
  border-color: rgba(148, 163, 184, 0.12);
  color: #e2e8f0;
}

html[data-theme='dark'] .nav_mod_toggle:hover,
html[data-theme='dark'] .nav_mod_icon_btn:hover,
html[data-theme='dark'] .nav_mod_theme_toggle:hover {
  background: hsla(256, 100%, 56%, 0.12);
  border-color: hsla(256, 100%, 56%, 0.25);
  color: #c7d2fe;
}

html[data-theme='dark'] .nav_mod_brand_main {
  color: #f1f5f9;
}

html[data-theme='dark'] .nav_mod_brand_sub {
  color: #64748b;
}

html[data-theme='dark'] .nav_mod_page_title h1 {
  color: #94a3b8;
}

html[data-theme='dark'] .nav_mod_page_title {
  border-left-color: rgba(148, 163, 184, 0.12);
}

html[data-theme='dark'] .nav_mod_profile_trigger {
  background: rgba(30, 41, 59, 0.8);
  border-color: rgba(148, 163, 184, 0.12);
}

html[data-theme='dark'] .nav_mod_profile_name {
  color: #e2e8f0;
}

html[data-theme='dark'] .nav_mod_avatar {
  background: linear-gradient(135deg, #1e3a5f, #1e40af);
}

html[data-theme='dark'] .nav_mod_avatar_fallback {
  color: #93c5fd;
}

html[data-theme='dark'] .nav_mod_sidebar {
  background: #0f172a;
  border-right-color: rgba(148, 163, 184, 0.08);
}

html[data-theme='dark'] .nav_mod_section_label {
  color: rgba(148, 163, 184, 0.45);
}

html[data-theme='dark'] .nav_mod_divider {
  border-top-color: rgba(148, 163, 184, 0.1);
}

html[data-theme='dark'] .nav_mod_link {
  color: #94a3b8;
}

html[data-theme='dark'] .nav_mod_link:hover {
  background: rgba(148, 163, 184, 0.08);
  color: #e2e8f0;
}

html[data-theme='dark'] .nav_mod_link.active {
  background: hsla(256, 100%, 56%, 0.12);
  color: #c7d2fe;
}

html[data-theme='dark'] .nav_mod_link.active i {
  color: #c7d2fe;
}

html[data-theme='dark'] .nav_mod_link.active::before {
  background: hsl(256, 100%, 56%);
}

html[data-theme='dark'] .nav_mod_popover_panel,
html[data-theme='dark'] .nav_mod_profile_menu {
  background: #1e293b;
  border-color: rgba(148, 163, 184, 0.1);
}

html[data-theme='dark'] .nav_mod_popover_head {
  border-bottom-color: rgba(148, 163, 184, 0.1);
}

html[data-theme='dark'] .nav_mod_popover_head strong {
  color: #f1f5f9;
}

html[data-theme='dark'] .nav_mod_profile_menu a {
  color: #cbd5e1;
}

html[data-theme='dark'] .nav_mod_profile_menu a:hover {
  background: hsla(256, 100%, 56%, 0.10);
  color: #c7d2fe;
}

html[data-theme='dark'] .nav_mod_profile_menu a:hover i {
  color: #c7d2fe;
}

html[data-theme='dark'] .nav_mod_link_danger {
  color: #fca5a5;
}

html[data-theme='dark'] .nav_mod_link_danger:hover {
  background: rgba(239, 68, 68, 0.1);
  color: #fca5a5;
}

html[data-theme='dark'] .nav_mod_profile_menu a.nav_mod_logout_link {
  border-top-color: rgba(148, 163, 184, 0.1);
}