/* ========================================
   COMPONENTS — Navbar, Cards, Buttons, etc.
   ======================================== */

/* --- Top Navigation Bar --- */
.top-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--bg-glass-border);
  z-index: 1000;
  display: flex;
  align-items: center;
  padding: 0 var(--space-6);
  transition: background var(--transition-base);
}

.top-nav .nav-brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-weight: 700;
  font-size: var(--fs-lg);
  color: var(--text-primary);
}

.top-nav .nav-brand .brand-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  background: var(--gradient-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--fs-lg);
}

.top-nav .nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  margin-left: auto;
}

.top-nav .nav-links a {
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-full);
  color: var(--text-secondary);
  font-size: var(--fs-sm);
  font-weight: 500;
  transition: all var(--transition-fast);
}

.top-nav .nav-links a:hover,
.top-nav .nav-links a.active {
  color: var(--text-primary);
  background: var(--bg-card);
}

/* --- Progress Bar --- */
.progress-bar-container {
  position: fixed;
  top: var(--nav-height);
  left: 0;
  right: 0;
  height: 3px;
  background: rgba(255, 255, 255, 0.05);
  z-index: 999;
}

.progress-bar {
  height: 100%;
  background: var(--gradient-primary);
  width: 0%;
  transition: width 150ms ease;
  border-radius: 0 var(--radius-full) var(--radius-full) 0;
}

/* --- Sidebar Navigation --- */
.sidebar-nav {
  position: fixed;
  left: 0;
  top: calc(var(--nav-height) + 3px);
  bottom: 0;
  width: var(--sidebar-width);
  background: rgba(10, 10, 15, 0.6);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-right: 1px solid var(--bg-glass-border);
  padding: var(--space-8) var(--space-4);
  overflow-y: auto;
  z-index: 998;
  transition: transform var(--transition-base);
}

.sidebar-nav .nav-section-title {
  font-size: var(--fs-xs);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: var(--space-4);
  padding: 0 var(--space-3);
  font-weight: 600;
}

.sidebar-nav .nav-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-3);
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  font-size: var(--fs-sm);
  font-weight: 500;
  transition: all var(--transition-fast);
  cursor: pointer;
  margin-bottom: var(--space-1);
  position: relative;
}

.sidebar-nav .nav-item:hover {
  color: var(--text-primary);
  background: var(--bg-card);
}

.sidebar-nav .nav-item.active {
  color: var(--accent-blue);
  background: rgba(79, 142, 247, 0.1);
}

.sidebar-nav .nav-item.active::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 3px;
  height: 60%;
  background: var(--accent-blue);
  border-radius: var(--radius-full);
}

.sidebar-nav .nav-item .item-number {
  width: 24px;
  height: 24px;
  border-radius: var(--radius-full);
  background: var(--bg-card);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--fs-xs);
  font-weight: 600;
  flex-shrink: 0;
}

.sidebar-nav .nav-item.active .item-number {
  background: rgba(79, 142, 247, 0.2);
  color: var(--accent-blue);
}

/* --- Glass Card --- */
.glass-card {
  background: var(--bg-glass);
  border: 1px solid var(--bg-glass-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition: all var(--transition-base);
}

.glass-card:hover {
  background: var(--bg-card-hover);
  border-color: rgba(255, 255, 255, 0.15);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-full);
  font-size: var(--fs-sm);
  font-weight: 600;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.btn-primary {
  background: var(--gradient-primary);
  color: white;
  box-shadow: var(--shadow-glow-blue);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 30px rgba(79, 142, 247, 0.5);
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--bg-glass-border);
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: rgba(255, 255, 255, 0.2);
}

.btn-outline {
  background: transparent;
  color: var(--accent-blue);
  border: 1px solid var(--accent-blue);
}

.btn-outline:hover {
  background: rgba(79, 142, 247, 0.1);
}

.btn-lg {
  padding: var(--space-4) var(--space-8);
  font-size: var(--fs-base);
}

/* --- Slide Image Container --- */
.slide-container {
  border-radius: var(--radius-xl);
  overflow: hidden;
  border: 1px solid var(--bg-glass-border);
  background: var(--bg-secondary);
  transition: all var(--transition-base);
  box-shadow: var(--shadow-lg);
}

.slide-container:hover {
  border-color: rgba(255, 255, 255, 0.15);
  box-shadow: 0 8px 40px rgba(0, 0, 0, 0.6);
}

.slide-container img {
  width: 100%;
  height: auto;
  display: block;
}

/* --- Interactive Demo Container --- */
.demo-container {
  background: var(--bg-glass);
  border: 1px solid var(--bg-glass-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  position: relative;
  overflow: hidden;
}

.demo-container::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-primary);
  opacity: 0.6;
}

.demo-header {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-6);
}

.demo-header .demo-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: var(--gradient-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--fs-xl);
}

.demo-header .demo-label {
  font-size: var(--fs-xs);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent-blue);
  font-weight: 600;
}

.demo-header .demo-title {
  font-size: var(--fs-lg);
  font-weight: 700;
}

/* --- Quiz Card --- */
.quiz-card {
  background: var(--bg-glass);
  border: 1px solid var(--bg-glass-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  position: relative;
  overflow: hidden;
}

.quiz-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-warm);
  opacity: 0.6;
}

.quiz-question {
  font-size: var(--fs-xl);
  font-weight: 700;
  margin-bottom: var(--space-6);
  line-height: 1.4;
}

.quiz-options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-4);
}

.quiz-option {
  background: var(--bg-card);
  border: 2px solid var(--bg-glass-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5) var(--space-6);
  font-size: var(--fs-base);
  font-weight: 500;
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--transition-base);
  text-align: center;
  line-height: 1.5;
}

.quiz-option:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent-blue);
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow-blue);
}

.quiz-option.correct {
  background: rgba(34, 197, 94, 0.15);
  border-color: var(--correct);
  box-shadow: 0 0 20px rgba(34, 197, 94, 0.2);
}

.quiz-option.incorrect {
  background: rgba(239, 68, 68, 0.15);
  border-color: var(--incorrect);
  box-shadow: 0 0 20px rgba(239, 68, 68, 0.2);
}

.quiz-option.disabled {
  pointer-events: none;
  opacity: 0.6;
}

.quiz-feedback {
  margin-top: var(--space-6);
  padding: var(--space-4) var(--space-6);
  border-radius: var(--radius-lg);
  font-size: var(--fs-sm);
  line-height: 1.6;
  display: none;
}

.quiz-feedback.show {
  display: block;
  animation: fadeInUp 0.3s ease;
}

.quiz-feedback.correct {
  background: rgba(34, 197, 94, 0.1);
  border: 1px solid rgba(34, 197, 94, 0.3);
  color: var(--correct);
}

.quiz-feedback.incorrect {
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid rgba(239, 68, 68, 0.3);
  color: var(--incorrect);
}

/* --- Tooltip --- */
.tooltip {
  position: relative;
}

.tooltip::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(-8px);
  background: var(--bg-secondary);
  color: var(--text-primary);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-sm);
  font-size: var(--fs-xs);
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-fast);
  border: 1px solid var(--bg-glass-border);
  z-index: 100;
}

.tooltip:hover::after {
  opacity: 1;
}

/* --- Badge / Tag --- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
  font-size: var(--fs-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.badge-blue {
  background: rgba(79, 142, 247, 0.15);
  color: var(--accent-blue);
}

.badge-violet {
  background: rgba(139, 92, 246, 0.15);
  color: var(--accent-violet);
}

.badge-cyan {
  background: rgba(6, 182, 212, 0.15);
  color: var(--accent-cyan);
}

.badge-coral {
  background: rgba(249, 115, 22, 0.15);
  color: var(--accent-coral);
}

.badge-green {
  background: rgba(34, 197, 94, 0.15);
  color: var(--accent-green);
}

/* --- Slider / Range --- */
.range-slider {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 6px;
  background: var(--bg-card);
  border-radius: var(--radius-full);
  outline: none;
  cursor: pointer;
}

.range-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--gradient-primary);
  cursor: pointer;
  box-shadow: var(--shadow-glow-blue);
  transition: transform var(--transition-fast);
}

.range-slider::-webkit-slider-thumb:hover {
  transform: scale(1.2);
}

/* --- Tab System --- */
.tab-nav {
  display: flex;
  gap: var(--space-1);
  background: var(--bg-card);
  border-radius: var(--radius-full);
  padding: var(--space-1);
  margin-bottom: var(--space-6);
}

.tab-btn {
  padding: var(--space-2) var(--space-5);
  border-radius: var(--radius-full);
  font-size: var(--fs-sm);
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

.tab-btn:hover {
  color: var(--text-primary);
}

.tab-btn.active {
  background: var(--gradient-primary);
  color: white;
  box-shadow: var(--shadow-glow-blue);
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

/* --- Responsive --- */
@media (max-width: 1024px) {
  .sidebar-nav {
    transform: translateX(-100%);
  }

  .sidebar-nav.open {
    transform: translateX(0);
  }

  .main-content {
    margin-left: 0 !important;
  }
}

@media (max-width: 768px) {
  .quiz-options {
    grid-template-columns: 1fr;
  }

  .glass-card {
    padding: var(--space-6);
  }

  .demo-container {
    padding: var(--space-6);
  }
}