/* --- Base Styles --- */
html,
body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: var(--bg-primary);
  overflow: hidden;
  transition: background-color 0.5s ease;
  font-family:
    -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial,
    sans-serif;
}

#tsparticles {
  width: 100%;
  height: 100%;
  position: absolute;
  top: 0;
  left: 0;
  z-index: 1;
  /* Smooth transitions for burst effect and opacity changes */
  transition:
    filter 0.15s ease-out,
    opacity 0.2s ease;
}

/* --- Glassmorphism Button Base Style --- */
.glass-button {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--glass-bg);
  border: var(--glass-border);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  display: flex;
  justify-content: center;
  align-items: center;
  cursor: pointer;
  transition: all 0.3s ease;
  color: var(--text-primary);
  -webkit-user-select: none;
  user-select: none;
  flex-shrink: 0;
  /* Ensure minimum touch target size for accessibility */
  min-width: 44px;
  min-height: 44px;
}
.glass-button:hover {
  background: var(--glass-bg-hover);
  transform: scale(1.1);
}

/* Subtle tap feedback for mobile */
.glass-button:active {
  transform: scale(0.95);
}

.glass-button.disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: scale(1) !important;
  background: var(--glass-bg) !important;
  pointer-events: none;
}

/* --- ACCESSIBILITY: Visible Focus Indicator --- */
.glass-button:focus-visible,
.modal-close-btn:focus-visible {
  outline: 3px solid var(--focus-outline-color);
  outline-offset: 3px;
  box-shadow: 0 0 10px var(--focus-outline-color);
}

#chaos-slider:focus-visible::-webkit-slider-thumb {
  outline: 3px solid var(--focus-outline-color);
  outline-offset: 3px;
}

/* --- ACCESSIBILITY: Visually Hidden Class for Screen Readers --- */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

/* --- Corner Buttons --- */
#fullscreen-btn {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 100;
}

/* --- Menu Styles --- */
.menu-container {
  position: fixed;
  bottom: 20px;
  left: 20px;
  z-index: 100;
  display: flex;
  align-items: flex-end;
  gap: 8px;
  max-width: calc(100vw - 20px);
  /* The collapsed sub-menu still reserves layout space (scaleX(0) doesn't
     shrink the box). Make the container transparent to pointer events and
     re-enable on interactive children so clicks pass through to the canvas. */
  pointer-events: none;
}

/* Menu toggle button is always interactive. The sub-menu re-enables
   pointer-events on itself via the existing `.menu-container.active .sub-menu`
   rule below, so it stays click-through while collapsed. */
.menu-container #main-menu-btn {
  pointer-events: auto;
}

#main-menu-btn svg {
  transition: transform 0.4s cubic-bezier(0.23, 1, 0.32, 1);
}
.menu-container.active #main-menu-btn svg {
  transform: rotate(90deg);
}

.menu-button.active {
  background: var(--button-active-bg);
  color: #fff;
}

.sub-menu {
  display: flex;
  flex-direction: column;
  gap: 8px;
  transform-origin: left center;
  transform: scaleX(0);
  opacity: 0;
  pointer-events: none;
  transition:
    transform 0.5s cubic-bezier(0.23, 1, 0.32, 1),
    opacity 0.3s ease;
  width: 308px;
  will-change: transform, opacity;
  padding: 12px;
  border-radius: 24px;
  background: var(--glass-bg);
  border: var(--glass-border);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  box-sizing: border-box;
}
/* --- ACCESSIBILITY: Style for fieldset to remove default styling --- */
.sub-menu fieldset {
  border: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.menu-container.active .sub-menu {
  transform: scaleX(1);
  opacity: 1;
  pointer-events: auto;
}

/* --- Intensity Slider --- */
.slider-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  height: 48px;
  border-radius: 24px;
  color: var(--text-primary);
  padding: 0 15px;
  box-sizing: border-box;
}
#chaos-slider {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 4px;
  background: var(--slider-track-bg);
  border-radius: 2px;
  outline: none;
  cursor: pointer;
  transition: background 0.3s;
}
#chaos-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 18px;
  height: 18px;
  background: #fff;
  border-radius: 50%;
  border: 2px solid var(--slider-thumb-border);
  transition: transform 0.2s ease;
}
#chaos-slider::-moz-range-thumb {
  width: 18px;
  height: 18px;
  background: #fff;
  border-radius: 50%;
  border: 2px solid var(--slider-thumb-border);
  transition: transform 0.2s ease;
}
#chaos-slider:hover::-webkit-slider-thumb,
#chaos-slider:hover::-moz-range-thumb {
  transform: scale(1.2);
}
#chaos-display {
  font-size: 18px;
  font-weight: bold;
  min-width: 24px;
  text-align: center;
  margin-left: 10px;
}

/* --- Sub-menu Divider --- */
.submenu-divider {
  flex-basis: 100%;
  height: 2px;
  background: var(--divider-color);
  margin: 8px 0;
  border: none;
  border-radius: 1px;
  opacity: 0.8;
}

/* --- Modal Styles --- */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.6);
  -webkit-backdrop-filter: blur(5px);
  backdrop-filter: blur(5px);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 200;
  opacity: 0;
  visibility: hidden;
  transition:
    opacity 0.4s ease,
    visibility 0.4s ease;
}
.modal-overlay.visible {
  opacity: 1;
  visibility: visible;
}
.modal-content {
  background: var(--modal-bg);
  color: var(--text-secondary);
  padding: 30px;
  border-radius: 20px;
  border: var(--modal-border);
  width: 90%;
  max-width: 550px;
  box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
  transform: scale(0.9);
  transition: transform 0.4s cubic-bezier(0.23, 1, 0.32, 1);
  max-height: 85vh;
  overflow-y: auto;
  text-align: center;
  will-change: transform;
  overscroll-behavior: contain;
}
.modal-overlay.visible .modal-content {
  transform: scale(1);
}
.modal-content h2 {
  margin-top: 0;
  border-bottom: var(--modal-header-border);
  padding-bottom: 10px;
}
.modal-content p {
  line-height: 1.6;
}
.modal-content strong {
  color: var(--text-strong);
}
.modal-content a {
  color: var(--link-color);
  text-decoration: none;
  transition: color 0.3s;
}
.modal-content a:hover {
  color: var(--link-color-hover);
}

.modal-close-btn {
  display: block;
  margin: 20px auto 0;
  padding: 12px 25px;
  border: none;
  border-radius: 25px;
  background: var(--button-active-bg);
  color: white;
  font-size: 16px;
  cursor: pointer;
  transition: all 0.3s ease;
  text-decoration: none;
  width: fit-content;
}

.modal-close-btn:hover {
  background: var(--button-active-bg-hover);
}

.modal-actions {
  display: flex;
  gap: 12px;
  align-items: center;
  margin-top: 20px;
}

.modal-actions .modal-close-btn {
  flex: 1;
  margin: 0;
}

.welcome-checkbox-label {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  cursor: pointer;
  white-space: nowrap;
}

.welcome-checkbox-label input {
  cursor: pointer;
}

.info-list {
  list-style: none;
  padding: 0;
}
.info-list li {
  display: flex;
  align-items: center;
  margin-bottom: 15px;
}
.info-list .icon-wrapper {
  width: 30px;
  height: 30px;
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-right: 15px;
}
.info-list .icon-wrapper svg {
  width: 20px;
  height: 20px;
}
.info-text {
  text-align: left;
}
.info-text strong {
  display: block;
  font-size: 1.1em;
  margin-bottom: 2px;
}
.info-text span {
  font-size: 0.9em;
  opacity: 0.8;
}
.info-text code,
#custom-tooltip code {
  font-family:
    'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, Courier, monospace;
  font-size: 0.9em;
  padding: 2px 5px;
  border-radius: 4px;
  background-color: rgba(0, 0, 0, 0.2);
  margin-left: 5px;
}
body.light-mode .info-text code,
body.light-mode #custom-tooltip code {
  background-color: rgba(0, 0, 0, 0.1);
}

/* Modal Tabs Styles */
.modal-tabs {
  display: flex;
  gap: 10px;
  margin: 15px 0 20px 0;
  border-bottom: 2px solid rgba(255, 255, 255, 0.1);
}

.modal-tab {
  background: transparent;
  border: none;
  border-bottom: 3px solid transparent;
  color: var(--text-color);
  padding: 10px 20px;
  cursor: pointer;
  font-size: 15px;
  font-weight: 500;
  transition: all 0.3s ease;
  margin-bottom: -2px;
  opacity: 0.6;
}

.modal-tab:hover {
  opacity: 0.9;
  background: rgba(255, 255, 255, 0.05);
}

.modal-tab.active {
  opacity: 1;
  border-bottom-color: var(--button-active-bg);
  color: var(--text-strong);
}

.modal-tab:focus-visible {
  outline: 2px solid var(--button-active-bg);
  outline-offset: 2px;
}

.modal-tab-content {
  display: none;
  animation: fadeIn 0.3s ease;
}

.modal-tab-content.active {
  display: block;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.modal-content-tabbed {
  max-width: 700px;
  max-height: 80vh;
  overflow-y: auto;
}

.advanced-settings-grid {
  display: flex;
  flex-direction: column;
  gap: 15px;
  text-align: left;
  margin-top: 10px;
}

.advanced-setting {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 16px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

body.light-mode .advanced-setting {
  background: rgba(0, 0, 0, 0.05);
  border-color: rgba(0, 0, 0, 0.08);
}

.advanced-setting h3 {
  margin: 0 0 6px 0;
  font-size: 1em;
  color: var(--text-strong);
}

.advanced-setting p {
  margin: 0;
  font-size: 0.9em;
  opacity: 0.85;
  line-height: 1.4;
}

.advanced-toggle {
  display: flex;
  align-items: center;
  gap: 10px;
}

.toggle-switch {
  position: relative;
  width: 48px;
  height: 26px;
  flex-shrink: 0;
}

.toggle-switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

.toggle-slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(255, 255, 255, 0.2);
  transition: 0.3s;
  border-radius: 34px;
}

.toggle-slider::before {
  position: absolute;
  content: '';
  height: 20px;
  width: 20px;
  left: 3px;
  top: 3px;
  background-color: #fff;
  transition: 0.3s;
  border-radius: 50%;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.2);
}

.toggle-switch input:checked + .toggle-slider {
  background-color: var(--button-active-bg);
}

.toggle-switch input:checked + .toggle-slider::before {
  transform: translateX(22px);
}

.advanced-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 15px;
}

.advanced-reset-btn,
.advanced-secondary-btn {
  padding: 10px 18px;
  border-radius: 999px;
  border: none;
  background: rgba(255, 255, 255, 0.12);
  color: var(--text-strong);
  cursor: pointer;
  transition: background 0.3s ease;
}

.advanced-secondary-btn {
  border: 1px solid rgba(255, 255, 255, 0.2);
  background: transparent;
}

.advanced-reset-btn:hover,
.advanced-secondary-btn:hover {
  background: rgba(255, 255, 255, 0.2);
}

.advanced-note {
  font-size: 0.85em;
  opacity: 0.75;
  text-align: left;
  margin-top: 10px;
}

/* Keyboard Shortcuts Modal Styles */
.shortcuts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  margin: 20px 0;
}

.shortcut-group h3 {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-strong);
  margin-bottom: 12px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  padding-bottom: 8px;
}

.shortcut-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 0;
  font-size: 14px;
}

.shortcut-item kbd {
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 4px;
  padding: 4px 8px;
  font-family: 'Courier New', monospace;
  font-size: 12px;
  font-weight: 600;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  min-width: 70px;
  text-align: center;
}

.shortcut-item span {
  color: var(--text-color);
  flex: 1;
  margin-left: 12px;
  text-align: left;
}

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

  .modal-tabs {
    gap: 5px;
  }

  .modal-tab {
    padding: 8px 12px;
    font-size: 14px;
  }

  .advanced-setting {
    flex-direction: column;
    align-items: flex-start;
  }

  .advanced-toggle {
    width: 100%;
    justify-content: space-between;
  }
}

/* --- Toast Notification --- */
#toast-notification {
  position: fixed;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--toast-bg);
  color: var(--text-primary);
  padding: 12px 25px;
  border-radius: 25px;
  z-index: 300;
  opacity: 0;
  visibility: hidden;
  transition:
    opacity 0.4s ease,
    visibility 0.4s ease,
    bottom 0.4s ease;
  font-size: 14px;
  -webkit-backdrop-filter: blur(5px);
  backdrop-filter: blur(5px);
  border: var(--toast-border);
}
#toast-notification.show {
  bottom: 100px;
  opacity: 1;
  visibility: visible;
}

/* --- Custom Tooltip --- */
#custom-tooltip {
  position: fixed;
  z-index: 999;
  padding: 10px 15px;
  border-radius: 12px;
  font-size: 14px;
  line-height: 1.5;
  max-width: 280px;
  text-align: left;
  pointer-events: none;
  opacity: 0;
  visibility: hidden;
  transform: scale(0.9);
  transition:
    opacity 0.2s ease,
    transform 0.2s ease,
    visibility 0.2s;

  background: var(--tooltip-bg);
  border: var(--tooltip-border);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  color: var(--tooltip-text);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
}
#custom-tooltip.visible {
  opacity: 1;
  visibility: visible;
  transform: scale(1);
}
#custom-tooltip strong {
  display: block;
  margin-bottom: 5px;
  font-weight: 600;
  color: var(--tooltip-strong-text);
}
#custom-tooltip span {
  opacity: 0.9;
}

/* --- Utility: Hide icons initially --- */
#icon-fullscreen-exit,
#icon-play,
#theme-icon-moon {
  display: none;
}

/* --- RESPONSIVENESS & REDUCED MOTION --- */
@media (max-width: 660px) {
  .sub-menu {
    /* Make width fluid to allow wrapping on smaller screens */
    width: calc(100vw - 90px);
    max-width: 380px;
  }

  /* Smaller buttons on mobile for 4-column grid */
  .glass-button {
    width: 44px;
    height: 44px;
  }

  /* Ensure 4-column layout on mobile */
  .sub-menu fieldset {
    gap: 6px;
  }

  .submenu-divider {
    width: 95%;
    margin: 4px auto;
  }
  .slider-container {
    max-width: 280px;
    width: 100%;
  }
}

/* Extra small screens - even smaller buttons */
@media (max-width: 400px) {
  .glass-button {
    width: 40px;
    height: 40px;
  }

  .sub-menu fieldset {
    gap: 5px;
  }

  .sub-menu {
    width: calc(100vw - 80px);
    padding: 10px;
  }
}

.keyboard-press {
  transform: scale(0.95);
  transition: transform 0.1s ease;
}

@media (prefers-reduced-motion: reduce) {
  /* Disable expensive blur effects and animations for users who prefer reduced motion */
  .glass-button,
  .modal-content,
  #toast-notification,
  #custom-tooltip,
  .slider-container {
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
  }
  * {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}