/* Base Variables & Modern Theming (Glassmorphism & Gradients) */
:root {
  --bg-color: #f8fafc;
  --bg-gradient: radial-gradient(circle at top right, #e0e7ff 0%, #f8fafc 40%, #f1f5f9 100%);
  --text-primary: #0f172a;
  --text-secondary: #334155; /* Better contrast */
  
  --card-bg: rgba(255, 255, 255, 0.85); /* More opaque */
  --header-bg: rgba(255, 255, 255, 0.9);
  --card-border: rgba(255, 255, 255, 0.9);
  --border-color: #cbd5e1;
  
  --primary: #3b82f6;
  --primary-hover: #2563eb;
  --primary-grad: linear-gradient(135deg, #3b82f6 0%, #6366f1 100%);
  --primary-glow: rgba(59, 130, 246, 0.4);
  
  --secondary: #64748b;
  --secondary-hover: #475569;
  
  --success: #059669; /* Darker green for contrast */
  --danger: #dc2626;  /* Darker red */
  --danger-hover: #b91c1c;
  --warning: #d97706; /* Darker orange */
  
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.04);
  --shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.05), 0 4px 6px -2px rgba(0, 0, 0, 0.03);
  --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  
  --radius: 16px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --blur: blur(12px);
}

[data-theme="dark"] {
  --bg-color: #09090b;
  --bg-gradient: radial-gradient(circle at top left, #1e1b4b 0%, #09090b 40%, #020617 100%);
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1; /* Increased contrast for dark mode */
  
  --card-bg: rgba(30, 41, 59, 0.75); /* More opaque */
  --header-bg: rgba(9, 9, 11, 0.85);
  --card-border: rgba(255, 255, 255, 0.1);
  --border-color: rgba(255, 255, 255, 0.12);
  
  --primary: #60a5fa;
  --primary-hover: #3b82f6;
  --primary-grad: linear-gradient(135deg, #60a5fa 0%, #818cf8 100%);
  --primary-glow: rgba(96, 165, 250, 0.3);
  
  --success: #10b981;
  --danger: #ef4444;
  --danger-hover: #dc2626;
  --warning: #f59e0b;
  
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.5);
  --shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
}

/* Reset & Global */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background-color: var(--bg-color);
  background-image: var(--bg-gradient);
  background-attachment: fixed;
  color: var(--text-primary);
  line-height: 1.6;
  transition: background-color var(--transition), color var(--transition);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* Typography & Utilities */
h1, h2, h3, h4 { font-weight: 700; color: var(--text-primary); letter-spacing: -0.02em; }
.text-gradient {
  background: var(--primary-grad);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}
.text-center { text-align: center; }
.text-secondary { color: var(--text-secondary); }
.hidden { display: none !important; }
.mb-3 { margin-bottom: 1rem; }
.mb-4 { margin-bottom: 1.5rem; }
.mt-4 { margin-top: 1.5rem; }
.py-4 { padding-top: 1.5rem; padding-bottom: 1.5rem; }
.py-5 { padding-top: 2rem; padding-bottom: 2rem; }
.px-5 { padding-left: 2rem; padding-right: 2rem; }
.mx-auto { margin-left: auto; margin-right: auto; }
.full-width { width: 100%; }

/* Icons */
.icon {
  width: 22px; height: 22px;
  fill: currentColor;
  display: inline-block;
  vertical-align: middle;
  transition: var(--transition);
}
.icon.sm { width: 16px; height: 16px; }
.icon.large { width: 54px; height: 54px; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 0.6rem 1.25rem;
  border: none;
  border-radius: 10px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  color: #fff;
  letter-spacing: 0.01em;
}
.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none !important;
  box-shadow: none !important;
}
.btn-primary { 
  background: var(--primary-grad);
  box-shadow: 0 4px 15px var(--primary-glow);
}
.btn-primary:hover:not(:disabled) { 
  transform: translateY(-2px);
  box-shadow: 0 6px 20px var(--primary-glow);
}
.btn-secondary { background-color: var(--secondary); }
.btn-secondary:hover:not(:disabled) { background-color: var(--secondary-hover); }
.btn-success { background-color: var(--success); }
.btn-danger { background-color: var(--danger); }
.btn-danger:hover:not(:disabled) { background-color: var(--danger-hover); }

.btn-large { padding: 0.85rem 1.8rem; font-size: 1.1rem; border-radius: 12px; }
.btn-icon { background: none; color: var(--text-primary); padding: 10px; border-radius: 50%; border: 1px solid transparent; }
.btn-icon:hover { background-color: var(--card-bg); border-color: var(--border-color); transform: scale(1.05);}
.btn-group { display: flex; gap: 15px; justify-content: center; }

/* Layout Header & Footer */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  background-color: var(--header-bg);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  border-bottom: 1px solid var(--border-color);
  position: sticky; top: 0; z-index: 100;
  box-shadow: var(--shadow-sm);
}
.logo { display: flex; align-items: center; gap: 12px; color: var(--primary); }
.logo h1 { font-size: 1.4rem; color: var(--text-primary); }

.footer {
  margin-top: auto;
  text-align: center;
  padding: 2.5rem 1rem;
  background-color: transparent;
  border-top: 1px solid var(--border-color);
  color: var(--text-secondary);
}
.footer p { font-size: 0.95rem; margin-bottom: 8px; }
.footer-note { font-size: 0.85rem; opacity: 0.7; }

/* Container */
.container {
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 1rem;
  flex: 1;
  width: 100%;
}

/* Glassmorphism Cards */
.card {
  background-color: var(--card-bg);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  border-radius: var(--radius);
  padding: 1.5rem 2rem;
  box-shadow: var(--shadow);
  border: 1px solid var(--card-border);
  display: flex;
  flex-direction: column;
}
.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border-color);
}
.card-title { display: flex; align-items: center; gap: 12px; }
.card-title h2 { font-size: 1.3rem; }

/* Feature Cards & Animations (Homepage) */
.feature-card {
  text-decoration: none;
  color: inherit;
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.3s ease, border-color 0.3s ease;
  display: block;
}
.feature-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-top: 0.5rem;
  line-height: 1.4;
}
.feature-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary);
}
.feature-card:hover .icon, .feature-card:hover h3 span {
  transform: scale(1.15) rotate(-5deg);
}

/* Badges */
.badge {
  padding: 6px 12px;
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  background-color: var(--secondary);
  color: #fff;
  letter-spacing: 0.02em;
}
.badge-success { background-color: rgba(16, 185, 129, 0.15); color: var(--success); border: 1px solid rgba(16, 185, 129, 0.3); }
.badge-danger { background-color: rgba(239, 68, 68, 0.15); color: var(--danger); border: 1px solid rgba(239, 68, 68, 0.3); }
.badge-warning { background-color: rgba(245, 158, 11, 0.15); color: var(--warning); border: 1px solid rgba(245, 158, 11, 0.3); }

/* Grid Layout */
.grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.8rem;
}

/* Form Inputs */
.device-selector { margin-bottom: 1.5rem; }
.device-selector label { display: block; font-size: 0.95rem; margin-bottom: 8px; color: var(--text-secondary); font-weight: 500;}
.select-input {
  width: 100%;
  padding: 0.8rem 1rem;
  border-radius: 10px;
  border: 1px solid var(--border-color);
  background-color: var(--bg-color);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 1rem;
  transition: var(--transition);
  appearance: none;
  cursor: pointer;
}
.select-input:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-glow); }

/* Video Preview */
.video-container {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  background-color: #000;
  border-radius: 12px;
  overflow: hidden;
  margin-bottom: 1.5rem;
  box-shadow: inset 0 2px 10px rgba(0,0,0,0.5);
}
#video-preview {
  width: 100%; height: 100%;
  object-fit: cover;
  transform: scaleX(-1);
}
.overlay-msg {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: rgba(0,0,0,0.8);
  color: #fff;
  font-weight: 500;
  font-size: 1.1rem;
}

/* Audio Visualizer */
.audio-visualizer-container {
  width: 100%;
  height: 120px;
  background-color: var(--bg-color);
  border-radius: 12px;
  border: 1px solid var(--border-color);
  margin-bottom: 1rem;
  display: flex; align-items: center; justify-content: center;
  overflow: hidden;
  box-shadow: inset 0 2px 5px rgba(0,0,0,0.05);
}
#mic-visualizer { width: 100%; height: 100%; }

/* Sound Wave Animation */
.sound-wave { display: flex; justify-content: center; gap: 6px; height: 30px; margin-bottom: 15px; align-items: center; }
.sound-wave span {
  display: block; width: 6px; background-color: var(--primary);
  border-radius: 3px; animation: bounce 1s infinite ease-in-out;
}
.sound-wave span:nth-child(1) { height: 10px; animation-delay: 0s; }
.sound-wave span:nth-child(2) { height: 20px; animation-delay: 0.1s; }
.sound-wave span:nth-child(3) { height: 30px; animation-delay: 0.2s; }
.sound-wave span:nth-child(4) { height: 20px; animation-delay: 0.3s; }
.sound-wave span:nth-child(5) { height: 10px; animation-delay: 0.4s; }
@keyframes bounce { 0%, 100% { transform: scaleY(1); } 50% { transform: scaleY(0.3); } }

/* Diagnostics List */
.stat-row { display: flex; justify-content: space-between; font-size: 1rem; margin-bottom: 8px; }
.diag-list { list-style: none; }
.diag-list li {
  display: flex; justify-content: space-between;
  padding: 1rem 0;
  border-bottom: 1px dashed var(--border-color);
}
.diag-list li:last-child { border-bottom: none; }
.diag-label { color: var(--text-secondary); font-weight: 500; }
.diag-value { font-weight: 600; }

/* Tips */
.tip { font-size: 0.9rem; color: var(--text-secondary); margin-top: auto; padding-top: 1rem; display: flex; gap: 8px; align-items: flex-start;}

/* Full Span Layout */
@media (min-width: 769px) {
  .full-span { grid-column: span 2; }
}

/* Mouse Tester */
.mouse-pad {
  border: 2px dashed rgb(148, 163, 184);
  border-radius: 16px;
  background-color: var(--bg-color);
  user-select: none;
  cursor: crosshair;
  transition: border-color 0.2s;
}
.mouse-pad:hover { border-color: var(--primary); }

.mouse-clicks { display: flex; justify-content: center; gap: 15px; }
.mouse-btn {
  padding: 1.25rem;
  border-radius: 12px;
  background-color: var(--card-bg);
  border: 2px solid var(--border-color);
  font-weight: 600;
  color: var(--text-secondary);
  transition: all 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  min-width: 100px;
  box-shadow: var(--shadow-sm);
}
.mouse-btn.active {
  background-color: var(--primary);
  color: #fff;
  border-color: var(--primary);
  transform: scale(0.92);
  box-shadow: 0 0 15px var(--primary-glow);
}

/* Keyboard Tester */
.keyboard-container { padding: 2rem 0; }
.kb-display {
  font-family: inherit;
  font-size: 5rem;
  font-weight: 800;
  background: var(--primary-grad);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  min-height: 100px;
  line-height: 1;
  text-shadow: 0 5px 15px rgba(0,0,0,0.1);
}
.kb-log { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; min-height: 35px; }
.kb-log span {
  padding: 8px 16px;
  background-color: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 600;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
  color: var(--text-primary);
}

/* Responsive */
.hidden-mobile { display: block; }
@media (max-width: 768px) {
  .header { padding: 1rem; }
  .logo h1 { font-size: 1.2rem; }
  .grid { grid-template-columns: 1fr; }
  .btn-large { width: 100%; }
  .hidden-mobile { display: none !important; }
}

.header-stop-btn.visible { display: inline-flex !important; }