/* Global App Shell - Left-side Navigation Rail */
/* Provides consistent navigation across reinischclassroom.com */

:root {
  --shell-bg: rgba(15, 23, 42, 0.92);
  --shell-border: rgba(255, 255, 255, 0.12);
  --shell-hover: rgba(255, 255, 255, 0.08);
  --shell-active: rgba(34, 197, 94, 0.15);
  --shell-text: #e6edf3;
  --shell-text-dim: #cbd5e1;
  --shell-accent: #22c55e;
  --shell-width: 260px;
  --shell-z: 1000;
}

/* Navigation rail container */
.app-shell-rail {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--shell-width);
  height: 100vh;
  background: var(--shell-bg);
  border-right: 1px solid var(--shell-border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  z-index: var(--shell-z);
  display: flex;
  flex-direction: column;
  box-shadow: 4px 0 24px rgba(0, 0, 0, 0.3);
  overflow-y: auto;
  overflow-x: hidden;
}

/* Shell header */
.app-shell-header {
  padding: 20px 16px 16px;
  border-bottom: 1px solid var(--shell-border);
  flex-shrink: 0;
}

.app-shell-brand {
  font-size: 16px;
  font-weight: 800;
  color: var(--shell-text);
  margin-bottom: 8px;
  letter-spacing: 0.3px;
}

.app-shell-tagline {
  font-size: 12px;
  color: var(--shell-text-dim);
  opacity: 0.8;
}

/* Navigation items */
.app-shell-nav {
  flex: 1;
  padding: 8px 0;
  overflow-y: auto;
}

.app-shell-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  color: var(--shell-text);
  text-decoration: none;
  cursor: pointer;
  transition: background 0.15s ease;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
  font-family: inherit;
  font-size: 14px;
  font-weight: 600;
}

.app-shell-item:hover {
  background: var(--shell-hover);
}

.app-shell-item.active {
  background: var(--shell-active);
  color: var(--shell-accent);
}

.app-shell-item-icon {
  font-size: 18px;
  width: 24px;
  text-align: center;
  flex-shrink: 0;
}

.app-shell-item-label {
  flex: 1;
}

.app-shell-item-arrow {
  font-size: 12px;
  opacity: 0.6;
  transition: transform 0.2s ease;
}

.app-shell-item.expanded .app-shell-item-arrow {
  transform: rotate(90deg);
}

/* Submenu */
.app-shell-submenu {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
  background: rgba(0, 0, 0, 0.15);
}

.app-shell-submenu.show {
  max-height: 500px;
}

.app-shell-submenu-item {
  display: block;
  padding: 10px 16px 10px 52px;
  color: var(--shell-text-dim);
  text-decoration: none;
  font-size: 13px;
  transition: all 0.15s ease;
  cursor: pointer;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
  font-family: inherit;
}

.app-shell-submenu-item:hover {
  color: var(--shell-text);
  background: var(--shell-hover);
  padding-left: 56px;
}

/* Footer actions */
.app-shell-footer {
  padding: 12px 16px;
  border-top: 1px solid var(--shell-border);
  flex-shrink: 0;
}

.app-shell-footer-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
  padding: 10px 16px;
  background: rgba(239, 68, 68, 0.15);
  border: 1px solid rgba(239, 68, 68, 0.3);
  border-radius: 8px;
  color: #fca5a5;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.15s ease;
  text-decoration: none;
}

.app-shell-footer-btn:hover {
  background: rgba(239, 68, 68, 0.25);
  border-color: rgba(239, 68, 68, 0.5);
}

/* Status indicator */
.app-shell-status {
  padding: 8px 16px;
  font-size: 11px;
  color: var(--shell-text-dim);
  opacity: 0.7;
  text-align: center;
  border-top: 1px solid var(--shell-border);
}

/* Mobile toggle button */
.app-shell-toggle {
  display: none;
  position: fixed;
  top: 16px;
  left: 16px;
  z-index: calc(var(--shell-z) + 1);
  width: 44px;
  height: 44px;
  background: var(--shell-bg);
  border: 1px solid var(--shell-border);
  border-radius: 8px;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  cursor: pointer;
  padding: 0;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.app-shell-toggle-icon {
  font-size: 20px;
}

/* Responsive behavior */
@media (max-width: 768px) {
  .app-shell-rail {
    transform: translateX(-100%);
    transition: transform 0.3s ease;
  }

  .app-shell-rail.open {
    transform: translateX(0);
  }

  .app-shell-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
  }
}

/* Adjust body padding to prevent content from being hidden under rail */
/* Only applies on desktop - mobile uses overlay behavior */
@media (min-width: 769px) {
  body.has-app-shell {
    padding-left: var(--shell-width);
  }
}

@media (max-width: 768px) {
  body.has-app-shell {
    padding-left: 0;
  }
}

/* Scrollbar styling for rail */
.app-shell-rail::-webkit-scrollbar {
  width: 8px;
}

.app-shell-rail::-webkit-scrollbar-track {
  background: rgba(255, 255, 255, 0.05);
}

.app-shell-rail::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.2);
  border-radius: 4px;
}

.app-shell-rail::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 255, 255, 0.3);
}

/* Accessibility */
.app-shell-item:focus,
.app-shell-submenu-item:focus,
.app-shell-footer-btn:focus {
  outline: 2px solid var(--shell-accent);
  outline-offset: -2px;
}

/* Hidden class for conditional display */
.app-shell-hidden {
  display: none !important;
}

/* Presentation Mode: Hide rail and expand content */
body.presentation-mode .app-shell-rail {
  display: none;
}

body.presentation-mode .app-shell-toggle {
  display: none;
}

body.presentation-mode.has-app-shell {
  padding-left: 0;
}

/* Presentation mode toggle button (will be added to top bars) */
.presentation-mode-toggle {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: 8px;
  color: var(--ink, #e6edf3);
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.15s ease;
}

.presentation-mode-toggle:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.22);
}

body.presentation-mode .presentation-mode-toggle {
  background: rgba(34, 197, 94, 0.15);
  border-color: rgba(34, 197, 94, 0.35);
  color: #22c55e;
}

/* Lessons Navigator Panel */
.lessons-navigator {
  position: fixed;
  top: 0;
  left: var(--shell-width);
  width: 340px;
  height: 100vh;
  background: var(--shell-bg);
  border-right: 1px solid var(--shell-border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  z-index: calc(var(--shell-z) - 1);
  display: flex;
  flex-direction: column;
  box-shadow: 4px 0 24px rgba(0, 0, 0, 0.3);
  transform: translateX(-100%);
  transition: transform 0.3s ease;
  overflow: hidden;
}

.lessons-navigator.open {
  transform: translateX(0);
}

.lessons-navigator-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 16px;
  border-bottom: 1px solid var(--shell-border);
  flex-shrink: 0;
}

.lessons-navigator-title {
  font-size: 18px;
  font-weight: 800;
  color: var(--shell-text);
  margin: 0;
}

.lessons-navigator-close {
  background: none;
  border: none;
  color: var(--shell-text);
  font-size: 28px;
  line-height: 1;
  cursor: pointer;
  padding: 0;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 4px;
  transition: background 0.15s ease;
}

.lessons-navigator-close:hover {
  background: var(--shell-hover);
}

.lessons-navigator-content {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
}

.lessons-loading {
  text-align: center;
  color: var(--shell-text-dim);
  padding: 20px;
}

.lessons-section {
  margin-bottom: 24px;
}

.lessons-section-title {
  font-size: 14px;
  font-weight: 800;
  color: var(--shell-accent);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 12px;
}

.lessons-unit {
  margin-bottom: 16px;
}

.lessons-unit-title {
  font-size: 13px;
  font-weight: 700;
  color: var(--shell-text);
  margin-bottom: 8px;
  padding: 8px 12px;
  background: rgba(255, 255, 255, 0.05);
  border-radius: 6px;
}

.lessons-presentations {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.lessons-presentation {
  background: none;
  border: none;
  color: var(--shell-text-dim);
  text-align: left;
  padding: 8px 12px 8px 24px;
  font-size: 13px;
  cursor: pointer;
  border-radius: 4px;
  transition: all 0.15s ease;
  font-family: inherit;
}

.lessons-presentation:hover {
  background: var(--shell-hover);
  color: var(--shell-text);
  padding-left: 28px;
}

.lessons-empty {
  color: var(--shell-text-dim);
  font-size: 13px;
  font-style: italic;
  padding: 8px 12px;
}

/* Presentation Viewer */
.presentation-viewer {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  background: var(--base, #0b1220);
  z-index: calc(var(--shell-z) - 2);
  display: none;
  flex-direction: column;
}

.presentation-viewer.open {
  display: flex;
  z-index: calc(var(--shell-z) + 10);
}

.presentation-viewer-controls {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  background: var(--shell-bg);
  border-bottom: 1px solid var(--shell-border);
  flex-shrink: 0;
}

.presentation-viewer-btn {
  padding: 8px 16px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: 6px;
  color: var(--shell-text);
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.15s ease;
  font-family: inherit;
}

.presentation-viewer-btn:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.22);
}

.presentation-viewer-btn[data-viewer-action="close"] {
  background: rgba(239, 68, 68, 0.15);
  border-color: rgba(239, 68, 68, 0.3);
  color: #fca5a5;
}

.presentation-viewer-btn[data-viewer-action="close"]:hover {
  background: rgba(239, 68, 68, 0.25);
  border-color: rgba(239, 68, 68, 0.5);
}

.presentation-viewer-frame {
  flex: 1;
  position: relative;
  overflow: hidden;
}

.presentation-iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
}

/* Presentation Mode adjustments for viewer */
body.presentation-mode .presentation-viewer-controls {
  display: none;
}

body.presentation-mode .lessons-navigator {
  display: none;
}

/* Mobile responsive */
@media (max-width: 768px) {
  .lessons-navigator {
    left: 0;
    width: 100%;
    max-width: 340px;
  }
  
  .lessons-navigator.open {
    transform: translateX(0);
  }
}

/* When viewer is open, adjust layout */
@media (min-width: 769px) {
  body.has-app-shell.viewer-open {
    padding-left: 0;
  }
}

/* Hide Netlify deploy-preview toolbar placeholder (blocked by CSP -> white slab) */
[data-netlify-deploy-id] { display: none !important; }