/* ========================================
   THEME VARIABLES - Professional Design
======================================== */
:root {
  /* Dark Theme (Default) - Refined Palette */
  --bg-primary: #0a0e1a;
  --bg-secondary: #12161f;
  --bg-tertiary: #1a1f2e;
  --card-bg: rgba(18, 22, 31, 0.85);
  --text-primary: #e4e7eb;
  --text-secondary: #9ca3af;
  --text-muted: #6b7280;
  --border-color: #1f2937;
  --shadow: rgba(0, 0, 0, 0.5);
  
  /* Minimal Accent - Single Professional Color */
  --accent-primary: #3b82f6;
  --accent-hover: #2563eb;
  --accent-light: rgba(59, 130, 246, 0.1);
  --accent-border: rgba(59, 130, 246, 0.3);
  
  /* Semantic Colors - Subtle */
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --info: #3b82f6;
  
  /* Glass Effect */
  --glass-bg: rgba(18, 22, 31, 0.7);
  --glass-border: rgba(255, 255, 255, 0.05);
}

[data-theme="light"] {
  /* Light Theme - Clean Professional */
  --bg-primary: #ffffff;
  --bg-secondary: #f9fafb;
  --bg-tertiary: #f3f4f6;
  --card-bg: rgba(255, 255, 255, 0.9);
  --text-primary: #111827;
  --text-secondary: #6b7280;
  --text-muted: #9ca3af;
  --border-color: #e5e7eb;
  --shadow: rgba(0, 0, 0, 0.08);
  
  --accent-light: rgba(59, 130, 246, 0.05);
  --accent-border: rgba(59, 130, 246, 0.2);
  
  --glass-bg: rgba(255, 255, 255, 0.7);
  --glass-border: rgba(0, 0, 0, 0.05);
}

/* ========================================
   GLOBAL STYLES
======================================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', 'Noto Kufi Arabic', 'Cairo', sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  transition: background 0.3s ease, color 0.3s ease;
  line-height: 1.6;
  letter-spacing: -0.01em;
}

/* ========================================
   NAVBAR - Clean & Professional
======================================== */
.glass-nav {
  background: var(--glass-bg) !important;
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--glass-border);
  box-shadow: 0 1px 3px var(--shadow);
  transition: all 0.3s ease;
}

.navbar-brand {
  font-weight: 600;
  font-size: 1.125rem;
  color: var(--text-primary) !important;
  transition: opacity 0.2s ease;
  letter-spacing: -0.02em;
}

.navbar-brand:hover {
  opacity: 0.8;
}

.brand-icon {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  background: var(--accent-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.2s ease;
}

.brand-icon:hover {
  transform: scale(1.05);
}

.brand-icon i {
  font-size: 1.25rem;
  color: white;
}

.brand-text {
  color: var(--text-primary);
}

/* Language Toggle - Minimal */
.lang-btn {
  border-radius: 6px !important;
  transition: all 0.2s ease;
  font-size: 0.875rem;
  padding: 0.375rem 0.75rem;
  border: 1px solid var(--border-color) !important;
  background: transparent !important;
  color: var(--text-secondary) !important;
}

.lang-btn:hover {
  background: var(--bg-tertiary) !important;
  border-color: var(--accent-border) !important;
}

.lang-btn.active {
  background: var(--accent-primary) !important;
  color: white !important;
  border-color: var(--accent-primary) !important;
}

/* Theme Toggle - Subtle */
#themeToggle {
  width: 36px;
  height: 36px;
  border-radius: 8px !important;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
  border: 1px solid var(--border-color) !important;
  background: transparent !important;
  color: var(--text-secondary) !important;
}

#themeToggle:hover {
  background: var(--bg-tertiary) !important;
  border-color: var(--accent-border) !important;
}

#themeIcon {
  font-size: 1rem;
  transition: transform 0.3s ease;
}

/* ========================================
   CARDS - Professional & Minimal
======================================== */
.gradient-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition: all 0.3s ease;
  overflow: hidden;
  box-shadow: 0 1px 3px var(--shadow);
}

.gradient-card:hover {
  border-color: var(--accent-border);
  box-shadow: 0 4px 12px var(--shadow);
}

.card-header.bg-gradient {
  background: var(--bg-secondary) !important;
  border-bottom: 1px solid var(--border-color) !important;
  padding: 1rem 1.5rem;
}

/* ========================================
   HERO SECTION - Refined
======================================== */
.hero-icon {
  width: 64px;
  height: 64px;
  border-radius: 12px;
  background: var(--accent-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.25);
}

.hero-icon i {
  font-size: 2rem;
  color: white;
}

.display-5 {
  color: var(--text-primary);
  font-weight: 600;
  letter-spacing: -0.03em;
}

.lead {
  color: var(--text-secondary);
  font-size: 1rem;
  font-weight: 400;
}

/* ========================================
   BUTTONS - Clean & Minimal
======================================== */
.btn {
  border-radius: 8px;
  font-weight: 500;
  transition: all 0.2s ease;
  border: 1px solid transparent;
  font-size: 0.9375rem;
  letter-spacing: -0.01em;
}

.btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 4px 8px var(--shadow);
}

.btn:active:not(:disabled) {
  transform: translateY(0);
}

.btn-success {
  background: var(--accent-primary) !important;
  border-color: var(--accent-primary) !important;
  color: white !important;
}

.btn-success:hover:not(:disabled) {
  background: var(--accent-hover) !important;
  border-color: var(--accent-hover) !important;
}

.btn-outline-warning {
  border-color: var(--border-color) !important;
  color: var(--text-primary) !important;
  background: transparent !important;
}

.btn-outline-warning:hover:not(:disabled) {
  background: var(--bg-tertiary) !important;
  border-color: var(--warning) !important;
  color: var(--warning) !important;
}

.btn-outline-info {
  border-color: var(--border-color) !important;
  color: var(--text-primary) !important;
  background: transparent !important;
}

.btn-outline-info:hover:not(:disabled) {
  background: var(--bg-tertiary) !important;
  border-color: var(--accent-primary) !important;
  color: var(--accent-primary) !important;
}

.btn-outline-primary {
  border-color: var(--border-color) !important;
  color: var(--text-primary) !important;
  background: transparent !important;
}

.btn-outline-primary:hover:not(:disabled) {
  background: var(--bg-tertiary) !important;
  border-color: var(--accent-primary) !important;
  color: var(--accent-primary) !important;
}

.btn-outline-danger {
  border-color: var(--border-color) !important;
  color: var(--text-primary) !important;
  background: transparent !important;
}

.btn-outline-danger:hover:not(:disabled) {
  background: var(--bg-tertiary) !important;
  border-color: var(--danger) !important;
  color: var(--danger) !important;
}

.btn i {
  font-size: 1.25rem;
}

/* ========================================
   INPUT GROUPS - Professional
======================================== */
.input-group-text {
  background: var(--bg-secondary) !important;
  border: 1px solid var(--border-color) !important;
  color: var(--text-secondary) !important;
}

.input-group-text.bg-gradient {
  background: var(--bg-tertiary) !important;
}

.form-control {
  background: var(--bg-secondary) !important;
  border: 1px solid var(--border-color) !important;
  color: var(--text-primary) !important;
  transition: all 0.2s ease;
  font-size: 0.9375rem;
}

.form-control:focus {
  background: var(--bg-tertiary) !important;
  border-color: var(--accent-primary) !important;
  box-shadow: 0 0 0 3px var(--accent-light) !important;
  color: var(--text-primary) !important;
}

.form-control::placeholder {
  color: var(--text-muted);
}

/* ========================================
   AUDIO CONTROLS - Minimal Design
======================================== */
.control-group {
  background: var(--bg-secondary);
  padding: 1rem;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  transition: all 0.2s ease;
}

.control-group:hover {
  border-color: var(--accent-border);
}

.form-label {
  color: var(--text-primary);
  font-weight: 500;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
}

.form-label i {
  font-size: 1rem;
  color: var(--text-secondary);
}

.form-range {
  cursor: pointer;
  height: 4px;
}

.form-range::-webkit-slider-thumb {
  background: var(--accent-primary);
  width: 16px;
  height: 16px;
  border-radius: 50%;
  transition: all 0.2s ease;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.form-range::-webkit-slider-thumb:hover {
  transform: scale(1.15);
  box-shadow: 0 0 0 4px var(--accent-light);
}

.form-range::-webkit-slider-runnable-track {
  background: var(--border-color);
  height: 4px;
  border-radius: 2px;
}

.form-range::-moz-range-thumb {
  background: var(--accent-primary);
  width: 16px;
  height: 16px;
  border-radius: 50%;
  border: none;
  transition: all 0.2s ease;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.form-range::-moz-range-thumb:hover {
  transform: scale(1.15);
  box-shadow: 0 0 0 4px var(--accent-light);
}

.form-range::-moz-range-track {
  background: var(--border-color);
  height: 4px;
  border-radius: 2px;
}

.range-value {
  text-align: center;
  margin-top: 0.5rem;
  padding: 0.25rem 0.625rem;
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border-radius: 6px;
  font-weight: 500;
  display: inline-block;
  font-size: 0.8125rem;
  border: 1px solid var(--border-color);
}

.form-check-input:checked {
  background-color: var(--accent-primary);
  border-color: var(--accent-primary);
}

.form-check-input {
  cursor: pointer;
}

/* ========================================
   VIDEO SECTION - Professional Layout
======================================== */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1rem;
}

.video-wrapper {
  position: relative;
  border-radius: 10px;
  overflow: hidden;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  box-shadow: 0 2px 8px var(--shadow);
  transition: all 0.3s ease;
}

.video-wrapper:hover {
  border-color: var(--accent-border);
  box-shadow: 0 4px 12px var(--shadow);
}

.video-element {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  min-height: 200px;
  background: var(--bg-tertiary);
}

.video-label {
  position: absolute;
  bottom: 8px;
  left: 8px;
  right: 8px;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  padding: 0.5rem 0.75rem;
  border-radius: 6px;
  color: white;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8125rem;
}

.video-label i {
  font-size: 1rem;
}

/* ========================================
   PARTICIPANTS TABLE - Clean Design
======================================== */
.table {
  color: var(--text-primary);
  margin-bottom: 0;
}

.table thead th {
  background: var(--bg-secondary);
  color: var(--text-secondary);
  font-weight: 600;
  text-transform: uppercase;
  font-size: 0.6875rem;
  letter-spacing: 0.05em;
  border-bottom: 1px solid var(--border-color) !important;
  padding: 0.875rem 1rem;
}

.table tbody td {
  background: transparent;
  border-bottom: 1px solid var(--border-color) !important;
  padding: 0.875rem 1rem;
  vertical-align: middle;
  font-size: 0.9375rem;
}

.table-hover tbody tr:hover {
  background: var(--bg-secondary) !important;
}

.id {
  font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', monospace;
  font-weight: 500;
  color: var(--text-primary);
  font-size: 0.875rem;
}

.me {
  color: var(--accent-primary) !important;
  font-weight: 600;
}

/* Talking Indicator - Subtle */
.dot {
  display: inline-block;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--border-color);
  transition: all 0.2s ease;
}

.talking {
  background: var(--success);
  box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7);
  animation: pulse-ring 1.5s cubic-bezier(0.24, 0, 0.38, 1) infinite;
}

@keyframes pulse-ring {
  0% {
    box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7);
  }
  50% {
    box-shadow: 0 0 0 6px rgba(16, 185, 129, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(16, 185, 129, 0);
  }
}

/* ========================================
   ALERTS - Subtle Information
======================================== */
.alert {
  border-radius: 8px;
  border: 1px solid var(--border-color);
  background: var(--bg-secondary);
  font-size: 0.9375rem;
}

.alert-info {
  background: var(--bg-secondary);
  border-color: var(--accent-border);
  color: var(--text-primary);
}

.alert-info i {
  color: var(--accent-primary);
}

.alert-dark {
  background: var(--bg-secondary);
  color: var(--text-primary);
}

/* ========================================
   UTILITIES
======================================== */
.hidden {
  display: none !important;
}

code {
  background: var(--bg-tertiary);
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
  color: var(--accent-primary);
  font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', monospace;
  font-size: 0.8125rem;
  border: 1px solid var(--border-color);
}

/* ========================================
   RESPONSIVE DESIGN
======================================== */
@media (max-width: 768px) {
  .hero-icon {
    width: 56px;
    height: 56px;
  }
  
  .hero-icon i {
    font-size: 1.75rem;
  }
  
  .display-5 {
    font-size: 1.75rem;
  }
  
  .video-grid {
    grid-template-columns: 1fr;
  }
  
  .navbar-brand {
    font-size: 1rem;
  }
  
  .brand-icon {
    width: 32px;
    height: 32px;
  }
  
  .brand-icon i {
    font-size: 1.125rem;
  }
  
  .btn {
    font-size: 0.875rem;
  }
  
  .btn i {
    font-size: 1.125rem;
  }
}

@media (max-width: 576px) {
  .control-group {
    padding: 0.75rem;
  }
  
  .gradient-card {
    border-radius: 10px;
  }
}

/* ========================================
   SCROLLBAR STYLING - Minimal
======================================== */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--accent-primary);
}

/* Firefox */
* {
  scrollbar-width: thin;
  scrollbar-color: var(--border-color) var(--bg-secondary);
}

/* ========================================
   SMOOTH TRANSITIONS
======================================== */
* {
  transition-property: background-color, border-color, color, opacity, transform;
  transition-duration: 0.2s;
  transition-timing-function: ease;
}

button, a, .btn, .form-control, .form-range {
  transition-duration: 0.15s;
}

/* ========================================
   FOCUS STATES - Accessibility
======================================== */
.btn:focus-visible,
.form-control:focus-visible,
.form-check-input:focus-visible,
.lang-btn:focus-visible,
#themeToggle:focus-visible {
  outline: 2px solid var(--accent-primary);
  outline-offset: 2px;
}

/* ========================================
   LOADING STATES
======================================== */
.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ========================================
   PROFESSIONAL SPACING
======================================== */
.card-body {
  padding: 1.5rem;
}

@media (min-width: 768px) {
  .card-body {
    padding: 2rem;
  }
}

/* ========================================
   TEXT HIERARCHY
======================================== */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

p {
  color: var(--text-secondary);
}

small {
  color: var(--text-muted);
  font-size: 0.875rem;
}