* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: "Roboto", sans-serif;
  overflow-x: hidden;
}

/* Hamburger Menu Button */
.hamburger-btn {
  display: flex;
  position: fixed;
  top: 15px;
  left: 15px;
  z-index: 1100;
  background: #3498db;
  border: none;
  width: 45px;
  height: 45px;
  border-radius: 8px;
  cursor: pointer;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
  transition: all 0.3s ease;
}

.hamburger-btn:hover {
  background: #2980b9;
  transform: scale(1.05);
}

.hamburger-btn span {
  display: block;
  width: 25px;
  height: 3px;
  background: #fff;
  border-radius: 2px;
  transition: all 0.3s ease;
}

.hamburger-btn.active span:nth-child(1) {
  transform: rotate(45deg) translate(7px, 7px);
}

.hamburger-btn.active span:nth-child(2) {
  opacity: 0;
}

.hamburger-btn.active span:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -7px);
}

.hamburger-btn.hidden {
  display: none;
}

/* Left Sidebar Navigation */
.left-sidebar {
  position: fixed;
  left: 0;
  top: 0;
  width: 280px;
  height: 100vh;
  background: linear-gradient(180deg, #1a1f3a 0%, #2c3e50 100%);
  color: #ecf0f1;
  overflow-y: auto;
  overflow-x: hidden;
  z-index: 1000;
  box-shadow: 4px 0 10px rgba(0, 0, 0, 0.1);
  transform: translateX(-100%);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.left-sidebar::-webkit-scrollbar {
  width: 8px;
}

.left-sidebar::-webkit-scrollbar-track {
  background: rgba(255, 255, 255, 0.05);
}

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

.left-sidebar::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 255, 255, 0.3);
}

.left-sidebar.active,
body.sidebar-open .left-sidebar {
  transform: translateX(0);
}

.sidebar-header {
  padding: 20px;
  background: rgba(0, 0, 0, 0.2);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  gap: 12px;
}

.sidebar-header h3 {
  font-size: 20px;
  font-weight: 700;
  margin: 0;
  color: #3498db;
  flex: 1;
}

.close-sidebar-btn {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.2);
  color: #ecf0f1;
  width: 36px;
  height: 36px;
  border-radius: 10px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 0.3s ease, transform 0.2s ease;
}

.close-sidebar-btn:hover {
  background: rgba(255, 255, 255, 0.18);
  transform: scale(1.05);
}

.sidebar-section {
  padding: 20px 15px;
}

.sidebar-section-title {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  color: #95a5a6;
  margin-bottom: 12px;
  letter-spacing: 1px;
}

.sidebar-link {
  display: block;
  padding: 12px 15px;
  margin-bottom: 6px;
  border-radius: 8px;
  color: #ecf0f1;
  text-decoration: none;
  transition: all 0.3s ease;
  font-size: 14px;
}

.sidebar-link:hover {
  background: rgba(52, 152, 219, 0.2);
  color: #fff;
  transform: translateX(5px);
}

.sidebar-dropdown {
  margin-bottom: 10px;
}

.sidebar-dropdown:last-child {
  margin-bottom: 0;
}

.sidebar-dropdown-toggle {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 15px;
  border: none;
  border-radius: 8px;
  background: transparent;
  color: #ecf0f1;
  font-size: 14px;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.3s ease;
}

.sidebar-dropdown-toggle:hover {
  background: rgba(52, 152, 219, 0.2);
  color: #fff;
  transform: translateX(5px);
}

.sidebar-dropdown-toggle:focus {
  outline: none;
  box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.4);
}

.sidebar-dropdown-toggle .toggle-label {
  display: flex;
  align-items: center;
  gap: 10px;
}

.sidebar-dropdown-toggle .toggle-icon {
  transition: transform 0.3s ease;
}

.sidebar-dropdown.open .sidebar-dropdown-toggle {
  background: rgba(52, 152, 219, 0.2);
  color: #fff;
}

.sidebar-dropdown.open .sidebar-dropdown-toggle .toggle-icon {
  transform: rotate(90deg);
}

.sidebar-submenu {
  display: none;
  margin-top: 6px;
}

.sidebar-dropdown.open .sidebar-submenu {
  display: block;
}

.sidebar-submenu .sidebar-link {
  padding-left: 35px;
}

.sidebar-link.active {
  background: #3498db;
  color: #fff;
  font-weight: 500;
}

.sidebar-link i {
  margin-right: 10px;
  width: 20px;
  text-align: center;
}

/* Main Content Area */
.main-content {
  min-height: 100vh;
  background: #f8f9fa;
  margin-left: 0;
  transition: margin-left 0.3s ease;
}

/* Top Header */
.top-header {
  background: #fff;
  padding: 15px 30px 15px 70px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 900;
}

.top-header h1 {
  margin: 0;
  font-size: 24px;
  color: #2c3e50;
}

/* Content Container */
.content-container {
  padding: 30px;
}

.content-box {
  background: #fff;
  border-radius: 12px;
  padding: 30px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  margin-bottom: 30px;
  font-size: 18px;
}

/* Audio Player Window */
#audioPlayerWindow {
  position: fixed;
  top: 20px;
  right: 20px;
  width: 280px;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
  z-index: 1050;
  display: none;
}

#audioPlayerHeader {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: #fff;
  padding: 12px 15px;
  border-radius: 12px 12px 0 0;
  cursor: move;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 600;
}

#closeAudio {
  background: rgba(255, 255, 255, 0.2);
  border: none;
  color: #fff;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  font-size: 20px;
  line-height: 1;
  cursor: pointer;
  transition: background 0.3s;
}

#closeAudio:hover {
  background: rgba(255, 255, 255, 0.3);
}

#audioPlayerControls {
  padding: 20px;
  text-align: center;
}

#audioPlayerControls button {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border: none;
  color: #fff;
  width: 45px;
  height: 45px;
  border-radius: 50%;
  font-size: 1.2rem;
  margin: 0 8px;
  cursor: pointer;
  transition:
    transform 0.2s,
    box-shadow 0.2s;
}

#audioPlayerControls button:hover {
  transform: scale(1.1);
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

#progressContainer {
  padding: 0 15px 15px 15px;
}

/* Text Chunks */
.chunk {
  color: #2c3e50;
  background-color: transparent;
  transition: all 0.3s ease;
  cursor: pointer;
  border-radius: 4px;
}

.chunk:hover,
.chunk.active {
  background-color: #e0ffff;
  color: #000;
}

.words {
  cursor: pointer;
  transition: background 0.3s;
  padding: 2px 4px;
  border-radius: 4px;
}

.words:hover,
.words.active {
  background-color: #e0ffff;
  color: #000;
}

/* Text Content */
.text-content {
  line-height: 2;
  font-size: 18px;
  color: blue;
}

/* Button Styling */
.btn-audio {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border: none;
  color: #fff;
  padding: 10px 24px;
  border-radius: 8px;
  font-weight: 600;
  transition:
    transform 0.2s,
    box-shadow 0.2s;
}

.btn-audio:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
  color: #fff;
}

/* Glossary Table */
.glossary-table {
  width: 100%;
}

.glossary-table td {
  padding: 12px 8px;
  border-bottom: 1px solid #e9ecef;
}

.glossary-title {
  font-size: 20px;
  font-weight: 700;
  color: #2c3e50;
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 3px solid #3498db;
}

hr {
  border: 0;
  height: 2px;
  background: linear-gradient(to right, #3498db, #9b59b6);
  margin: 30px 0;
}

@media (min-width: 769px) {
  body.sidebar-open .main-content {
    margin-left: 280px;
  }
}

/* Responsive Design */
@media (max-width: 768px) {
  .top-header {
    padding-left: 70px;
  }

  #audioPlayerWindow {
    width: calc(100% - 40px);
    left: 20px;
    right: 20px;
  }
}
.blue {
  background-color: #d6defe;
  font-size: 1.5em;
  font-weight: 600;
}
.comment {
  color: #5b5b5b;
  font-weight: 500;
  font-size: 0.9em;
  font-style: italic;
}