@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600&family=Outfit:wght@300;400;600;700&display=swap');

:root {
  --font-heading: 'Outfit', sans-serif;
  --font-body: 'Inter', sans-serif;
  
  /* Theme Colors (Default Bioluminescent Ocean) */
  --theme-glow: rgba(0, 242, 254, 0.6);
  --theme-accent: #00f2fe;
  --theme-accent-rgb: 0, 242, 254;
  --theme-bg-gradient: linear-gradient(135deg, #020024 0%, #050515 50%, #002f3c 100%);
  
  /* UI Colors */
  --ui-bg: rgba(10, 10, 20, 0.45);
  --ui-border: rgba(255, 255, 255, 0.08);
  --ui-text: #e2e8f0;
  --ui-text-muted: #94a3b8;
  --ui-active: #ffffff;
  
  /* Breath state transition duration (synchronized via JS, but nice to have defaults) */
  --breath-duration: 4s;
  --breath-scale: 1;
}

/* Scrollbar styles for the dashboard panel */
::-webkit-scrollbar {
  width: 6px;
}
::-webkit-scrollbar-track {
  background: transparent;
}
::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.1);
  border-radius: 10px;
}
::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 255, 255, 0.2);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  user-select: none;
  -webkit-user-select: none;
}

body, html {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: #020208;
  color: var(--ui-text);
  font-family: var(--font-body);
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

#canvas-container {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
}

/* Loading/Start Screen Overlay */
#overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  background: radial-gradient(circle at center, #05071a 0%, #010206 100%);
  z-index: 100;
  transition: opacity 1.5s cubic-bezier(0.25, 1, 0.5, 1), visibility 1.5s;
  text-align: center;
  padding: 20px;
}

#overlay.fade-out {
  opacity: 0;
  visibility: hidden;
}

.intro-content {
  max-width: 600px;
  opacity: 0;
  transform: translateY(20px);
  animation: fadeInUp 1.2s forwards 0.2s;
}

.intro-title {
  font-family: var(--font-heading);
  font-size: 3.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, #ffffff 30%, var(--theme-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 12px;
  filter: drop-shadow(0 0 15px rgba(var(--theme-accent-rgb), 0.25));
}

.intro-subtitle {
  font-size: 1.15rem;
  color: var(--ui-text-muted);
  margin-bottom: 40px;
  line-height: 1.6;
}

.start-btn {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: #fff;
  font-family: var(--font-heading);
  font-size: 1.1rem;
  font-weight: 500;
  padding: 16px 40px;
  border-radius: 50px;
  cursor: pointer;
  outline: none;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: all 0.4s cubic-bezier(0.2, 0.8, 0.2, 1);
  box-shadow: 0 0 0 rgba(var(--theme-accent-rgb), 0);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.start-btn:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--theme-accent);
  box-shadow: 0 0 25px rgba(var(--theme-accent-rgb), 0.4);
  transform: translateY(-2px);
  letter-spacing: 0.08em;
}

.start-btn:active {
  transform: translateY(0);
}

.instruction-text {
  margin-top: 24px;
  font-size: 0.85rem;
  color: var(--ui-text-muted);
  opacity: 0.6;
}

/* Glassmorphism Controls Dashboard */
.dashboard {
  position: absolute;
  top: 30px;
  right: 30px;
  width: 350px;
  max-height: calc(100vh - 60px);
  overflow-y: auto;
  background: var(--ui-bg);
  border: 1px solid var(--ui-border);
  border-radius: 20px;
  padding: 28px;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.4);
  z-index: 10;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  transition: opacity 0.5s ease, transform 0.5s cubic-bezier(0.16, 1, 0.3, 1);
  opacity: 0;
  transform: translateX(40px);
  pointer-events: none;
}

.dashboard.visible {
  opacity: 1;
  transform: translateX(0);
  pointer-events: all;
}

.dashboard-header {
  margin-bottom: 24px;
}

.dashboard-title {
  font-family: var(--font-heading);
  font-size: 1.6rem;
  font-weight: 600;
  color: #fff;
  margin-bottom: 4px;
  letter-spacing: -0.01em;
}

.dashboard-tagline {
  font-size: 0.85rem;
  color: var(--ui-text-muted);
}

.section-title {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ui-text-muted);
  margin-bottom: 14px;
  margin-top: 24px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  padding-bottom: 6px;
}

/* Button Group (Theme Selectors) */
.theme-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  margin-bottom: 20px;
}

.theme-btn {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--ui-border);
  color: var(--ui-text-muted);
  border-radius: 12px;
  padding: 14px 10px;
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.25, 1, 0.5, 1);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
}

.theme-btn:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.2);
  color: #fff;
}

.theme-btn.active {
  background: rgba(var(--theme-accent-rgb), 0.12);
  border-color: var(--theme-accent);
  color: #fff;
  box-shadow: 0 0 15px rgba(var(--theme-accent-rgb), 0.2);
}

.theme-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  box-shadow: 0 0 8px currentColor;
}

.theme-ocean .theme-dot { color: #00f2fe; }
.theme-aurora .theme-dot { color: #00ff87; }
.theme-sunset .theme-dot { color: #ff5e62; }
.theme-nebula .theme-dot { color: #bd00ff; }

/* Control Sliders */
.control-group {
  margin-bottom: 16px;
}

.control-label-wrapper {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
}

.control-label {
  font-size: 0.9rem;
  color: var(--ui-text);
  font-weight: 500;
}

.control-val {
  font-size: 0.8rem;
  color: var(--ui-text-muted);
}

/* Custom Range Input */
input[type=range] {
  -webkit-appearance: none;
  width: 100%;
  background: transparent;
}

input[type=range]:focus {
  outline: none;
}

input[type=range]::-webkit-slider-runnable-track {
  width: 100%;
  height: 4px;
  cursor: pointer;
  background: rgba(255, 255, 255, 0.15);
  border-radius: 2px;
}

input[type=range]::-webkit-slider-thumb {
  height: 16px;
  width: 16px;
  border-radius: 50%;
  background: #ffffff;
  cursor: pointer;
  -webkit-appearance: none;
  margin-top: -6px;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.5);
  transition: background 0.2s, transform 0.2s;
}

input[type=range]::-webkit-slider-thumb:hover {
  background: var(--theme-accent);
  transform: scale(1.15);
}

input[type=range].active-slider::-webkit-slider-thumb {
  background: var(--theme-accent);
}

/* Segmented Buttons */
.segmented-control {
  display: flex;
  background: rgba(0, 0, 0, 0.2);
  border: 1px solid var(--ui-border);
  border-radius: 12px;
  padding: 3px;
  margin-bottom: 16px;
}

.segmented-btn {
  flex: 1;
  background: transparent;
  border: none;
  color: var(--ui-text-muted);
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 500;
  padding: 10px 0;
  border-radius: 9px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.segmented-btn:hover {
  color: #fff;
}

.segmented-btn.active {
  background: rgba(255, 255, 255, 0.1);
  color: #fff;
}

/* Switch Styles */
.switch-wrapper {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.switch {
  position: relative;
  display: inline-block;
  width: 44px;
  height: 24px;
}

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

.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(255, 255, 255, 0.15);
  transition: .3s cubic-bezier(0.2, 0.8, 0.2, 1);
  border-radius: 24px;
}

.slider:before {
  position: absolute;
  content: "";
  height: 18px;
  width: 18px;
  left: 3px;
  bottom: 3px;
  background-color: white;
  transition: .3s cubic-bezier(0.2, 0.8, 0.2, 1);
  border-radius: 50%;
  box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

input:checked + .slider {
  background-color: var(--theme-accent);
}

input:checked + .slider:before {
  transform: translateX(20px);
}

/* Interactive Overlay / Audio Prompt */
#audio-prompt {
  background: rgba(var(--theme-accent-rgb), 0.1);
  border: 1px dashed var(--theme-accent);
  padding: 12px;
  border-radius: 12px;
  font-size: 0.8rem;
  color: #fff;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 10px;
  animation: glowPulse 2s infinite alternate;
}

#audio-prompt.hidden {
  display: none;
}

/* Guided Breathing Overlay (HUD) */
#breath-hud {
  position: absolute;
  bottom: 6%;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  pointer-events: none;
  text-align: center;
  transition: opacity 1s ease-in-out;
  opacity: 0;
}

#breath-hud.visible {
  opacity: 1;
}

.breath-circle-outer {
  width: 140px;
  height: 140px;
  border-radius: 50%;
  border: 2px solid rgba(255, 255, 255, 0.08);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  margin-bottom: 20px;
  box-shadow: 0 0 30px rgba(0, 0, 0, 0.3);
}

.breath-circle-inner {
  width: 100px;
  height: 100px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--theme-glow) 0%, rgba(var(--theme-accent-rgb), 0.2) 70%, rgba(var(--theme-accent-rgb), 0) 100%);
  filter: drop-shadow(0 0 15px rgba(var(--theme-accent-rgb), 0.6));
  position: absolute;
  transform: scale(var(--breath-scale));
  transition: transform var(--breath-duration) cubic-bezier(0.4, 0, 0.2, 1);
  opacity: 0.8;
}

.breath-instruction {
  font-family: var(--font-heading);
  font-size: 1.8rem;
  font-weight: 600;
  color: #fff;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 6px;
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.6);
  height: 2.2rem;
  transition: color 0.5s ease;
}

.breath-timer {
  font-size: 1rem;
  color: var(--ui-text-muted);
  font-weight: 500;
  text-shadow: 0 1px 6px rgba(0, 0, 0, 0.6);
}

/* User Guide bottom-left */
.bottom-guide {
  position: absolute;
  bottom: 30px;
  left: 30px;
  z-index: 10;
  pointer-events: none;
  font-family: var(--font-body);
  font-size: 0.85rem;
  color: var(--ui-text-muted);
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 1s forwards 1.2s, transform 1s forwards 1.2s;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.bottom-guide.visible {
  opacity: 0.6;
  transform: translateY(0);
}

.guide-item {
  display: flex;
  align-items: center;
  gap: 8px;
}

.guide-key {
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 4px;
  padding: 2px 6px;
  font-family: monospace;
  font-size: 0.75rem;
}

/* Toggle Menu button (for mobile or to hide settings) */
.toggle-settings-btn {
  position: absolute;
  top: 30px;
  left: 30px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--ui-bg);
  border: 1px solid var(--ui-border);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 10;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
  transition: all 0.3s ease;
  opacity: 0;
  pointer-events: none;
}

.toggle-settings-btn.visible {
  opacity: 1;
  pointer-events: all;
}

.toggle-settings-btn:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--theme-accent);
  box-shadow: 0 0 15px rgba(var(--theme-accent-rgb), 0.3);
  transform: scale(1.05);
}

.toggle-settings-btn svg {
  width: 20px;
  height: 20px;
  fill: currentColor;
  transition: transform 0.5s ease;
}

.toggle-settings-btn.active svg {
  transform: rotate(180deg);
}

/* Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(25px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes glowPulse {
  from {
    box-shadow: 0 0 4px rgba(var(--theme-accent-rgb), 0.2);
    border-color: rgba(var(--theme-accent-rgb), 0.4);
  }
  to {
    box-shadow: 0 0 12px rgba(var(--theme-accent-rgb), 0.6);
    border-color: rgba(var(--theme-accent-rgb), 1);
  }
}

/* Responsive adjustments */
@media (max-width: 768px) {
  .dashboard {
    position: fixed;
    top: 90px;
    right: 20px;
    left: 20px;
    width: auto;
    max-height: calc(100vh - 120px);
    transform: translateY(30px);
  }
  
  .dashboard.visible {
    transform: translateY(0);
  }
  
  .intro-title {
    font-size: 2.4rem;
  }
  
  #breath-hud {
    bottom: 5%;
  }
  
  .breath-circle-outer {
    width: 110px;
    height: 110px;
  }
  
  .breath-circle-inner {
    width: 80px;
    height: 80px;
  }
  
  .bottom-guide {
    display: none;
  }
}