/* Modern Algorithm Visualizer Pro Styles */

:root {
  /* Color Palette */
  --bg-primary: #0a0a0f;
  --bg-secondary: #1a1a2e;
  --bg-tertiary: #16213e;
  --bg-surface: #1e1e2e;
  --bg-elevated: #2a2a3e;
  --bg-glass: rgba(26, 26, 46, 0.8);

  /* Text Colors */
  --text-primary: #ffffff;
  --text-secondary: #b4bcd0;
  --text-muted: #7c8da6;
  --text-accent: #64b5f6;

  /* Brand Colors */
  --brand-primary: #6366f1;
  --brand-secondary: #8b5cf6;
  --brand-tertiary: #06b6d4;

  /* Status Colors */
  --success: #10b981;
  --warning: #f59e0b;
  --error: #ef4444;
  --info: #3b82f6;

  /* Algorithm Colors */
  --algo-compare: #ff6b6b;
  --algo-swap: #feca57;
  --algo-sorted: #4ecdc4;
  --algo-current: #ff9ff3;
  --algo-secondary: #45b7d1;
  --algo-primary: #6366f1;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  --shadow-glow: 0 0 20px rgba(99, 102, 241, 0.3);

  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-normal: 300ms ease-in-out;
  --transition-slow: 500ms ease-in-out;

  /* Typography */
  --font-family: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'Fira Code', 'Monaco', 'Cascadia Code', monospace;

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-weight: 400;
  line-height: 1.6;
  color: var(--text-primary);
  background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 50%, var(--bg-tertiary) 100%);
  background-attachment: fixed;
  min-height: 100vh;
  overflow-x: hidden;
  font-feature-settings: 'kern' 1, 'liga' 1;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Loading Screen */
.loading-screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--bg-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  opacity: 1;
  transition: opacity var(--transition-slow);
}

.loading-screen.hidden {
  opacity: 0;
  pointer-events: none;
}

.loading-content {
  text-align: center;
}

.loading-spinner {
  width: 60px;
  height: 60px;
  border: 4px solid var(--bg-elevated);
  border-top: 4px solid var(--brand-primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin: 0 auto var(--space-6);
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

/* Header */
.header {
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  padding: var(--space-6) 0;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-lg);
}

.header-content {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--space-6);
  display: flex;
  flex-direction: column;
  gap: var(--space-8);
}

.brand {
  text-align: center;
}

.brand-title {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  margin-bottom: var(--space-2);
  background: linear-gradient(135deg, var(--brand-primary), var(--brand-secondary), var(--brand-tertiary));
  background-size: 200% 200%;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: gradientShift 3s ease-in-out infinite;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-3);
}

.brand-icon {
  font-size: 0.8em;
  filter: drop-shadow(0 0 10px rgba(99, 102, 241, 0.5));
}

.brand-subtitle {
  color: var(--text-secondary);
  font-size: 1.1rem;
  font-weight: 400;
}

@keyframes gradientShift {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

/* Controls Grid */
.controls-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  grid-template-areas:
    "category algorithm speed size"
    "actions actions actions settings";
  gap: var(--space-4);
  align-items: end;
}

.control-group:nth-child(1) { grid-area: category; }
.control-group:nth-child(2) { grid-area: algorithm; }
.control-group:nth-child(3) { grid-area: speed; }
.control-group:nth-child(4) { grid-area: size; }
.control-actions { grid-area: actions; }
.control-settings { grid-area: settings; }

.control-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.control-label {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.label-text {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.label-icon {
  opacity: 0.7;
}

.label-value {
  background: var(--bg-elevated);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
  font-weight: 600;
  color: var(--text-accent);
  font-size: 0.75rem;
}

/* Form Controls */
.control-select {
  appearance: none;
  background: var(--bg-elevated);
  border: 2px solid transparent;
  border-radius: var(--radius-lg);
  color: var(--text-primary);
  font-size: 1rem;
  font-weight: 500;
  padding: var(--space-4);
  transition: all var(--transition-fast);
  cursor: pointer;
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3e%3cpath stroke='%236b7280' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='M6 8l4 4 4-4'/%3e%3c/svg%3e");
  background-position: right var(--space-3) center;
  background-repeat: no-repeat;
  background-size: 1.5em 1.5em;
  padding-right: var(--space-10);
}

.control-select:focus {
  outline: none;
  border-color: var(--brand-primary);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.control-select:hover {
  background: var(--bg-surface);
}

.control-slider {
  appearance: none;
  background: var(--bg-elevated);
  height: 8px;
  border-radius: var(--radius-full);
  outline: none;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.control-slider::-webkit-slider-thumb {
  appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--brand-primary), var(--brand-secondary));
  cursor: pointer;
  box-shadow: var(--shadow-lg);
  transition: all var(--transition-fast);
}

.control-slider::-webkit-slider-thumb:hover {
  transform: scale(1.1);
  box-shadow: var(--shadow-glow);
}

.control-slider::-moz-range-thumb {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--brand-primary), var(--brand-secondary));
  cursor: pointer;
  border: none;
  box-shadow: var(--shadow-lg);
  transition: all var(--transition-fast);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  border: 2px solid transparent;
  border-radius: var(--radius-lg);
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  position: relative;
  overflow: hidden;
  white-space: nowrap;
}

.btn::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 50%;
  transform: translate(-50%, -50%);
  transition: width 0.3s, height 0.3s;
}

.btn:hover::before {
  width: 300px;
  height: 300px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--brand-primary), var(--brand-secondary));
  color: white;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

.btn-secondary {
  background: var(--bg-elevated);
  color: var(--text-primary);
  border-color: rgba(255, 255, 255, 0.1);
}

.btn-secondary:hover {
  background: var(--bg-surface);
  border-color: var(--brand-primary);
}

.btn-accent {
  background: linear-gradient(135deg, var(--warning), #f97316);
  color: white;
}

.btn-accent:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 25px rgba(249, 115, 22, 0.3);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border: none;
  padding: var(--space-3);
  border-radius: var(--radius-md);
}

.btn-ghost:hover {
  background: var(--bg-elevated);
  color: var(--text-primary);
}

.btn-icon {
  font-size: 1.1em;
}

/* Control Actions */
.control-actions {
  display: flex;
  gap: var(--space-3);
  justify-content: center;
  flex-wrap: wrap;
}

.control-settings {
  display: flex;
  gap: var(--space-2);
  justify-content: flex-end;
}

/* Main Content */
.main-content {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-4);
  padding: var(--space-6);
  max-width: 1400px;
  margin: 0 auto;
  width: 100%;
}

.main-content.battle-mode {
  grid-template-columns: 1fr 1fr;
}

/* Visualization Containers */
.visualization-container {
  position: relative;
  background: var(--bg-surface);
  border: 2px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-xl);
  min-height: 500px;
  backdrop-filter: blur(10px);
}

.visualization-container::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, transparent, rgba(99, 102, 241, 0.05), transparent);
  pointer-events: none;
  z-index: 1;
}

.battle-canvas {
  display: none;
}

.main-content.battle-mode .battle-canvas {
  display: block;
}

.visualization-canvas {
  width: 100%;
  height: 100%;
  display: block;
  min-height: 500px;
  position: relative;
  z-index: 2;
}

/* Overlay Panels */
.overlay-panels {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  pointer-events: none;
  z-index: 10;
}

.stats-panel {
  position: absolute;
  top: var(--space-4);
  left: var(--space-4);
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  font-size: 0.875rem;
  min-width: 180px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  pointer-events: auto;
}

.stats-panel > div {
  margin: var(--space-2) 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.stats-panel strong {
  color: var(--text-primary);
}

.stat-value {
  color: var(--text-accent);
  font-weight: 600;
  font-family: var(--font-mono);
}

.algorithm-info {
  position: absolute;
  bottom: var(--space-4);
  right: var(--space-4);
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-lg);
  font-size: 0.875rem;
  font-weight: 500;
  max-width: 400px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  pointer-events: auto;
}

.performance-indicator {
  position: absolute;
  top: var(--space-4);
  right: var(--space-4);
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  padding: var(--space-3);
  border-radius: var(--radius-lg);
  border: 1px solid rgba(255, 255, 255, 0.1);
  pointer-events: auto;
  min-width: 120px;
}

.performance-bar {
  width: 80px;
  height: 6px;
  background: var(--bg-elevated);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: var(--space-2);
}

.performance-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--success), var(--warning), var(--error));
  border-radius: var(--radius-full);
  width: 0%;
  transition: width var(--transition-normal);
}

.performance-text {
  font-size: 0.75rem;
  color: var(--text-secondary);
  text-align: center;
  display: block;
}

/* Modal Panels */
.keyboard-shortcuts,
.settings-panel,
.help-panel {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(0.9);
  background: var(--bg-surface);
  border: 2px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  box-shadow: var(--shadow-xl);
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
  backdrop-filter: blur(20px);
  max-width: 90vw;
  max-height: 90vh;
  overflow-y: auto;
}

.keyboard-shortcuts.visible,
.settings-panel.visible,
.help-panel.visible {
  opacity: 1;
  visibility: visible;
  transform: translate(-50%, -50%) scale(1);
}

.keyboard-shortcuts h3,
.settings-panel h3,
.help-panel h3 {
  margin-bottom: var(--space-6);
  color: var(--text-primary);
  font-size: 1.5rem;
  font-weight: 600;
}

/* Keyboard Shortcuts */
.shortcuts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-4);
}

.shortcut {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-3);
  background: var(--bg-elevated);
  border-radius: var(--radius-lg);
}

.key {
  background: var(--bg-primary);
  color: var(--text-primary);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-md);
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 600;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.action {
  color: var(--text-secondary);
  font-weight: 500;
}

/* Settings Panel */
.settings-content,
.help-content {
  max-width: 500px;
}

.setting-group {
  margin-bottom: var(--space-6);
}

.setting-label {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  cursor: pointer;
  user-select: none;
  font-weight: 500;
}

.setting-label input[type="checkbox"] {
  display: none;
}

.checkmark {
  width: 20px;
  height: 20px;
  background: var(--bg-elevated);
  border: 2px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-sm);
  position: relative;
  transition: all var(--transition-fast);
}

.setting-label input[type="checkbox"]:checked + .checkmark {
  background: var(--brand-primary);
  border-color: var(--brand-primary);
}

.checkmark::after {
  content: '✓';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(0);
  color: white;
  font-size: 12px;
  font-weight: bold;
  transition: transform var(--transition-fast);
}

.setting-label input[type="checkbox"]:checked + .checkmark::after {
  transform: translate(-50%, -50%) scale(1);
}

.volume-slider {
  width: 100%;
  margin: var(--space-2) 0;
}

.volume-value {
  color: var(--text-accent);
  font-weight: 600;
  font-size: 0.875rem;
}

.setting-actions {
  display: flex;
  gap: var(--space-3);
  justify-content: flex-end;
  margin-top: var(--space-8);
}

/* Help Panel */
.help-section {
  margin-bottom: var(--space-6);
}

.help-section h4 {
  color: var(--text-primary);
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: var(--space-3);
}

.help-section p,
.help-section li {
  color: var(--text-secondary);
  line-height: 1.6;
}

.help-section ul {
  margin: var(--space-3) 0;
  padding-left: var(--space-5);
}

.help-section li {
  margin: var(--space-2) 0;
}

/* Backdrop */
.backdrop {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  z-index: 999;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
  backdrop-filter: blur(4px);
}

.backdrop.visible {
  opacity: 1;
  visibility: visible;
}

/* Footer */
.footer {
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: var(--space-6) 0;
  margin-top: var(--space-12);
}

.footer-content {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--space-6);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-4);
}

.footer-content p {
  color: var(--text-muted);
  font-size: 0.875rem;
}

.footer-links {
  color: var(--text-muted);
  font-size: 0.875rem;
  display: flex;
  gap: var(--space-3);
}

/* Responsive Design */
@media (max-width: 1200px) {
  .controls-grid {
    grid-template-areas:
      "category algorithm"
      "speed size"
      "actions actions"
      "settings settings";
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  :root {
    --space-6: 1rem;
  }

  .header-content {
    padding: 0 var(--space-4);
  }

  .controls-grid {
    grid-template-areas:
      "category"
      "algorithm"
      "speed"
      "size"
      "actions"
      "settings";
    grid-template-columns: 1fr;
  }

  .control-actions {
    flex-direction: column;
  }

  .control-settings {
    justify-content: center;
  }

  .main-content {
    padding: var(--space-4);
    gap: var(--space-3);
  }

  .main-content.battle-mode {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr 1fr;
  }

  .stats-panel,
  .algorithm-info,
  .performance-indicator {
    position: relative;
    margin: var(--space-2);
    background: var(--bg-surface);
  }

  .overlay-panels {
    position: static;
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-2);
    padding: var(--space-4);
    background: var(--bg-primary);
  }

  .visualization-canvas {
    min-height: 300px;
  }

  .footer-content {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .brand-title {
    font-size: 1.5rem;
  }

  .keyboard-shortcuts,
  .settings-panel,
  .help-panel {
    padding: var(--space-4);
    margin: var(--space-4);
    max-width: calc(100vw - 2rem);
  }
}

/* High Contrast Mode */
.high-contrast {
  --bg-primary: #000000;
  --bg-secondary: #1a1a1a;
  --bg-surface: #2a2a2a;
  --text-primary: #ffffff;
  --text-secondary: #cccccc;
  --brand-primary: #0099ff;
  --algo-compare: #ff0000;
  --algo-swap: #ffff00;
  --algo-sorted: #00ff00;
}

/* Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in-up {
  animation: fadeInUp 0.5s ease-out;
}

/* Scrollbar Styling */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-elevated);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb {
  background: var(--brand-primary);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--brand-secondary);
}

/* Focus Styles for Accessibility */
*:focus {
  outline: 2px solid var(--brand-primary);
  outline-offset: 2px;
}

button:focus,
select:focus,
input:focus {
  outline: none;
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.3);
}

/* Print Styles */
@media print {
  .header,
  .footer,
  .keyboard-shortcuts,
  .settings-panel,
  .help-panel,
  .backdrop {
    display: none;
  }

  body {
    background: white;
    color: black;
  }

  .main-content {
    padding: 0;
  }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .loading-spinner {
    animation: none;
  }
}

/* Dark Mode Support */
@media (prefers-color-scheme: light) {
  :root {
    --bg-primary: #f8fafc;
    --bg-secondary: #f1f5f9;
    --bg-surface: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
  }
}