html {
  font-family: 'Google Sans Flex', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  font-variation-settings: 'ROND' 100;
}

:root {
  color-scheme: light dark;
  /* =========================================
     LIGHT THEME (Default)
     ========================================= */
  --bg-color: #d4dce8;
  --card-bg: rgba(255, 255, 255, 0.28);
  --card-border: rgba(255, 255, 255, 0.35);
  
  --text-primary: #0f172a;
  --text-secondary: #334155;
  --text-muted: #64748b;
  
  --accent-blue: #3b82f6;
  --accent-glow: rgba(96, 165, 250, 0.15);
  --accent-gradient: linear-gradient(135deg, #93c5fd, #60a5fa);
  
  /* Neomorphic Shadows for Light Theme (Refined) */
  --neo-shadow-out: -6px -6px 14px rgba(255, 255, 255, 0.65), 6px 6px 14px rgba(125, 138, 162, 0.3);
  --neo-shadow-in: inset -3px -3px 8px rgba(255, 255, 255, 0.65), inset 3px 3px 8px rgba(125, 138, 162, 0.22);
  --neo-shadow-hover: -8px -8px 20px rgba(255, 255, 255, 0.65), 8px 8px 20px rgba(125, 138, 162, 0.38);
  --btn-border: 1px solid rgba(255, 255, 255, 0.4);
  --card-glow: inset 0 0 20px rgba(255, 255, 255, 0.12);
  --card-glow-hover: inset 0 0 25px rgba(255, 255, 255, 0.18);
  
  /* Background Video Tweaks for Light Mode */
  --video-opacity: 0.38;
  --video-filter: brightness(1.05) contrast(0.92) saturate(1.05) blur(3px) hue-rotate(10deg);
  --overlay-bg: radial-gradient(circle at center, rgba(212, 220, 232, 0.15) 0%, rgba(212, 220, 232, 0.88) 100%);
  
  /* Brand Hover Colors - Light Mode */
  --hover-tiktok: #010101;
  --hover-telegram: #0088cc;
  --hover-bluesky: #0285ff;
  --hover-twitter: #0f1419;
  --hover-instagram: #c13584;
  --hover-youtube: #ff0000;
  --hover-discord: #5865f2;

  /* Component Theme Variables - Light Mode */
  --profile-pic-border: 3px solid rgba(255, 255, 255, 0.8);
  --profile-pic-shadow: 0 6px 12px rgba(163, 177, 198, 0.25);
  --user-name-gradient: linear-gradient(to bottom, var(--text-primary) 60%, var(--text-secondary) 100%);
  --location-card-bg: rgba(255, 255, 255, 0.2);
  --social-btn-bg: rgba(255, 255, 255, 0.24);
  --slider-track-bg: rgba(163, 177, 198, 0.25);
  --slider-thumb-bg: #ffffff;
  --volume-btn-hover-bg: rgba(255, 255, 255, 0.12);
}

/* Explicit Dark Theme */
html.dark-theme,
body.dark-theme {
  color-scheme: dark;
  /* =========================================
     DARK THEME
     ========================================= */
  --bg-color: #080c16;
  --card-bg: rgba(13, 25, 48, 0.45);
  --card-border: rgba(255, 255, 255, 0.08);
  
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  
  --accent-blue: #60a5fa;
  --accent-glow: rgba(96, 165, 250, 0.4);
  --accent-gradient: linear-gradient(135deg, #93c5fd, #3b82f6);
  
  /* Neomorphic Shadows for Dark Theme (Refined for maximum depth and pop) */
  --neo-shadow-out: 
    -6px -6px 14px rgba(255, 255, 255, 0.025), 
    -2px -2px 6px rgba(96, 165, 250, 0.08), 
    6px 6px 16px rgba(0, 0, 0, 0.45);
  --neo-shadow-in: 
    inset -3px -3px 8px rgba(255, 255, 255, 0.015), 
    inset -1px -1px 3px rgba(96, 165, 250, 0.06), 
    inset 3px 3px 8px rgba(0, 0, 0, 0.5);
  --neo-shadow-hover: 
    -8px -8px 20px rgba(255, 255, 255, 0.04), 
    -3px -3px 8px rgba(96, 165, 250, 0.12), 
    8px 8px 20px rgba(0, 0, 0, 0.55);
  --btn-border: 1px solid rgba(255, 255, 255, 0.04);
  --card-glow: inset 0 0 20px rgba(255, 255, 255, 0.03);
  --card-glow-hover: inset 0 0 25px rgba(255, 255, 255, 0.05);
  
  /* Background Video Tweaks for Dark Mode */
  --video-opacity: 0.5;
  --video-filter: brightness(0.6) contrast(1.1) saturate(1.2) blur(2px);
  --overlay-bg: radial-gradient(circle at center, rgba(8, 12, 22, 0.2) 0%, rgba(8, 12, 22, 0.8) 100%);
  
  /* Brand Hover Colors - Dark Mode */
  --hover-tiktok: #ffffff;
  --hover-telegram: #38bdf8;
  --hover-bluesky: #208bfe;
  --hover-twitter: #f8fafc;
  --hover-instagram: #f472b6;
  --hover-youtube: #f87171;
  --hover-discord: #818cf8;

  /* Component Theme Variables - Dark Mode */
  --profile-pic-border: 3px solid rgba(255, 255, 255, 0.2);
  --profile-pic-shadow: 0 6px 12px rgba(0, 0, 0, 0.4);
  --user-name-gradient: linear-gradient(to bottom, #ffffff 60%, #cbd5e1 100%);
  --location-card-bg: rgba(8, 12, 22, 0.35);
  --social-btn-bg: rgba(13, 25, 48, 0.28);
  --slider-track-bg: rgba(8, 12, 22, 0.4);
  --slider-thumb-bg: var(--text-primary);
  --volume-btn-hover-bg: rgba(255, 255, 255, 0.05);
}

html.light-theme,
body.light-theme {
  color-scheme: light;
}

/* System Dark Mode Synchronization (automatically active if user prefers dark and haven't manually locked light mode) */
@media (prefers-color-scheme: dark) {
  :root:not(.light-theme) {
    color-scheme: dark;
    --bg-color: #080c16;
    --card-bg: rgba(13, 25, 48, 0.45);
    --card-border: rgba(255, 255, 255, 0.08);
    
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    
    --accent-blue: #60a5fa;
    --accent-glow: rgba(96, 165, 250, 0.4);
    --accent-gradient: linear-gradient(135deg, #93c5fd, #3b82f6);
    
    --neo-shadow-out: 
      -6px -6px 14px rgba(255, 255, 255, 0.025), 
      -2px -2px 6px rgba(96, 165, 250, 0.08), 
      6px 6px 16px rgba(0, 0, 0, 0.45);
    --neo-shadow-in: 
      inset -3px -3px 8px rgba(255, 255, 255, 0.015), 
      inset -1px -1px 3px rgba(96, 165, 250, 0.06), 
      inset 3px 3px 8px rgba(0, 0, 0, 0.5);
    --neo-shadow-hover: 
      -8px -8px 20px rgba(255, 255, 255, 0.04), 
      -3px -3px 8px rgba(96, 165, 250, 0.12), 
      8px 8px 20px rgba(0, 0, 0, 0.55);
    --btn-border: 1px solid rgba(255, 255, 255, 0.04);
    --card-glow: inset 0 0 20px rgba(255, 255, 255, 0.03);
    --card-glow-hover: inset 0 0 25px rgba(255, 255, 255, 0.05);
    
    --video-opacity: 0.5;
    --video-filter: brightness(0.6) contrast(1.1) saturate(1.2) blur(2px);
    --overlay-bg: radial-gradient(circle at center, rgba(8, 12, 22, 0.2) 0%, rgba(8, 12, 22, 0.8) 100%);
    
    --hover-tiktok: #ffffff;
    --hover-telegram: #38bdf8;
    --hover-bluesky: #208bfe;
    --hover-twitter: #f8fafc;
    --hover-instagram: #f472b6;
    --hover-youtube: #f87171;
    --hover-discord: #818cf8;

    /* Component Theme Variables - Dark Mode */
    --profile-pic-border: 3px solid rgba(255, 255, 255, 0.2);
    --profile-pic-shadow: 0 6px 12px rgba(0, 0, 0, 0.4);
    --user-name-gradient: linear-gradient(to bottom, #ffffff 60%, #cbd5e1 100%);
    --location-card-bg: rgba(8, 12, 22, 0.35);
    --social-btn-bg: rgba(13, 25, 48, 0.28);
    --slider-track-bg: rgba(8, 12, 22, 0.4);
    --slider-thumb-bg: var(--text-primary);
    --volume-btn-hover-bg: rgba(255, 255, 255, 0.05);
  }
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: inherit;
  font-variation-settings: inherit;
  -webkit-tap-highlight-color: transparent;
}

body {
  font-family: 'Google Sans Flex', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  font-variation-settings: 'ROND' 100;
  background-color: var(--bg-color);
  color: var(--text-primary);
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  justify-content: center;
  align-items: center;
  overflow: hidden;
  position: relative;
  -webkit-overflow-scrolling: touch;
  /* Smooth theme transitions */
  transition: background-color 0.4s cubic-bezier(0.16, 1, 0.3, 1), color 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

button, a.social-btn {
  touch-action: manipulation;
}

/* Background Video Styling */
.video-background-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -2;
  overflow: hidden;
  background-color: var(--bg-color);
}

.video-background-container video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: var(--video-opacity);
  filter: var(--video-filter);
  /* Promotes video to its own hardware-accelerated layer to optimize CSS filter blending performance */
  transform: translate3d(0, 0, 0);
  backface-visibility: hidden;
  will-change: opacity, filter;
  transition: opacity 0.4s cubic-bezier(0.16, 1, 0.3, 1), filter 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.video-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
  background: var(--overlay-bg);
  transition: background 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Main Container */
.container {
  width: 100%;
  max-width: 480px;
  padding: 24px;
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 1;
}

/* Glass-Neomorphic Card */
.profile-card {
  width: 100%;
  background: var(--card-bg);
  backdrop-filter: blur(25px);
  -webkit-backdrop-filter: blur(25px);
  border: var(--card-border);
  border-radius: 36px;
  padding: 40px 32px;
  /* Apply system variables for light/dark shadow definitions */
  box-shadow: 
    var(--neo-shadow-out),
    var(--card-glow);
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  /* Smooth theme transitions */
  transition: 
    transform 0.4s cubic-bezier(0.16, 1, 0.3, 1), 
    box-shadow 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    background-color 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    border-color 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  transform: translateZ(0);
  will-change: transform, box-shadow;
}

.profile-card:hover {
  transform: translateY(-4px);
  box-shadow: 
    var(--neo-shadow-hover),
    var(--card-glow-hover);
}

/* Profile Picture Area */
.profile-pic-wrapper {
  position: relative;
  width: 130px;
  height: 130px;
  border-radius: 50%;
  margin-bottom: 16px;
  padding: 6px;
  background: rgba(255, 255, 255, 0.2);
  box-shadow: var(--neo-shadow-in);
  display: flex;
  justify-content: center;
  align-items: center;
  transition: background-color 0.4s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.profile-pic-wrapper::before {
  content: '';
  position: absolute;
  top: -2px;
  left: -2px;
  right: -2px;
  bottom: -2px;
  border-radius: 50%;
  background: var(--accent-gradient);
  z-index: -1;
  opacity: 0.6;
  filter: blur(4px);
  transition: opacity 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.profile-pic {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  object-fit: cover;
  border: var(--profile-pic-border);
  box-shadow: var(--profile-pic-shadow);
  transition: border-color 0.4s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

/* User Info & Typography (Material 3 Expressive) */
.user-name {
  font-size: 2.2rem;
  font-weight: 850;
  font-stretch: 105%;
  letter-spacing: -0.03em;
  color: var(--text-primary);
  margin-bottom: 16px;
  background: var(--user-name-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  font-variation-settings: 'wght' 850, 'wdth' 105, 'opsz' 40, 'ROND' 100;
}

/* Location Card / Time Zone */
.location-card {
  width: 100%;
  background: var(--location-card-bg);
  border-radius: 20px;
  padding: 12px 18px;
  margin-bottom: 20px;
  box-shadow: var(--neo-shadow-in);
  display: flex;
  justify-content: space-around;
  align-items: center;
  border: var(--btn-border);
  transition: background-color 0.4s cubic-bezier(0.16, 1, 0.3, 1), border-color 0.4s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.location-item {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.location-label {
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  color: var(--text-muted);
  letter-spacing: 0.08em;
  margin-bottom: 4px;
  font-variation-settings: 'wght' 600, 'ROND' 100;
  transition: color 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.location-val {
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text-secondary);
  font-variation-settings: 'wght' 500, 'ROND' 100;
  transition: color 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

#local-time {
  font-weight: 700;
  color: var(--text-primary);
  font-variant-numeric: tabular-nums;
  font-variation-settings: 'wght' 700, 'ROND' 100;
  transition: color 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Social Grid - 6 buttons */
.social-grid {
  width: 100%;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.social-btn {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  aspect-ratio: 1;
  border-radius: 24px; /* Playful Material 3 curves */
  background: var(--social-btn-bg);
  border: var(--btn-border);
  color: var(--text-secondary);
  box-shadow: var(--neo-shadow-out);
  cursor: pointer;
  text-decoration: none;
  transform: translateZ(0);
  will-change: transform, box-shadow;
  transition: 
    transform 0.25s cubic-bezier(0.16, 1, 0.3, 1),
    background-color 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    border-color 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    box-shadow 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    color 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
  overflow: hidden;
}

.social-btn svg {
  width: 28px;
  height: 28px;
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), fill 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

.social-btn:not(.telegram) svg {
  fill: currentColor;
}

/* Telegram monochrome-by-default logic */
.social-btn.telegram svg {
  transform: scale(1.18);
}

.social-btn.telegram:hover svg {
  transform: scale(1.28);
}

.social-btn.telegram .telegram-bg {
  fill: transparent;
  transition: fill 0.25s ease;
}

.social-btn.telegram .telegram-plane {
  fill: currentColor;
  transition: fill 0.25s ease;
}

.social-btn.telegram:hover .telegram-bg {
  fill: url(#Oval_1_);
}

.social-btn.telegram:hover .telegram-plane {
  fill: #FFFFFF;
}

.social-btn span {
  margin-top: 8px;
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  font-variation-settings: 'wght' 500, 'ROND' 100;
}

/* Hover and Press States (Neomorphism) */
.social-btn:hover {
  color: var(--text-primary);
  box-shadow: var(--neo-shadow-hover);
  transform: translateY(-2px);
}

.social-btn:hover svg {
  transform: scale(1.12);
}

.social-btn::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at center, rgba(37, 99, 235, 0.08) 0%, transparent 70%);
  opacity: 0;
  transition: opacity 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.social-btn:hover::after {
  opacity: 1;
}

.social-btn:active {
  box-shadow: var(--neo-shadow-in);
  transform: translateY(1px);
}

/* Dynamic Brand Hover Accents from theme variables */
.social-btn.tiktok:hover { color: var(--hover-tiktok); }
.social-btn.telegram:hover { color: var(--hover-telegram); }
.social-btn.bluesky:hover { color: var(--hover-bluesky); }
.social-btn.twitter:hover { color: var(--hover-twitter); }
.social-btn.instagram:hover { color: var(--hover-instagram); }
.social-btn.youtube:hover { color: var(--hover-youtube); }
.social-btn.discord:hover { color: var(--hover-discord); }

/* Floating Top-Right Controls Container */
.controls-container-top {
  position: fixed;
  top: 24px;
  right: 24px;
  display: flex;
  align-items: center;
  gap: 16px;
  z-index: 100;
  transform: translateZ(0);
}

.control-btn {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--card-bg);
  backdrop-filter: blur(15px);
  -webkit-backdrop-filter: blur(15px);
  border: var(--btn-border);
  box-shadow: var(--neo-shadow-out);
  cursor: pointer;
  display: flex;
  justify-content: center;
  align-items: center;
  color: var(--text-primary);
  flex-shrink: 0;
  outline: none;
  transition: 
    transform 0.3s cubic-bezier(0.16, 1, 0.3, 1),
    background-color 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    border-color 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    color 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    box-shadow 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.control-btn:hover {
  box-shadow: var(--neo-shadow-hover);
  transform: scale(1.08);
}

.control-btn:active {
  box-shadow: var(--neo-shadow-in);
  transform: scale(0.96);
}

.theme-icon {
  width: 20px;
  height: 20px;
  fill: currentColor;
  transition: transform 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.theme-toggle-btn:hover .theme-icon {
  transform: rotate(25deg);
}

.theme-icon.hidden {
  display: none;
}

/* Pure CSS Instant Theme Icon Synchronization */
#theme-icon-moon {
  display: block;
}

#theme-icon-sun {
  display: none;
}

html.dark-theme #theme-icon-moon,
body.dark-theme #theme-icon-moon {
  display: none !important;
}

html.dark-theme #theme-icon-sun,
body.dark-theme #theme-icon-sun {
  display: block !important;
}

@media (prefers-color-scheme: dark) {
  :root:not(.light-theme) #theme-icon-moon {
    display: none !important;
  }
  :root:not(.light-theme) #theme-icon-sun {
    display: block !important;
  }
}

.volume-btn-toggle {
  position: relative;
}

.volume-btn-toggle svg {
  width: 20px;
  height: 20px;
  fill: currentColor;
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1), opacity 0.25s ease;
}

.volume-btn-toggle .volume-icon-close {
  position: absolute;
  opacity: 0;
  transform: rotate(-90deg) scale(0.6);
  pointer-events: none;
}

.volume-btn-toggle .volume-icon-speaker {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

/* When volume card is open (not collapsed), outer toggle button displays the Exit (X) icon */
.volume-slider-card:not(.collapsed) + .volume-btn-toggle .volume-icon-speaker {
  opacity: 0;
  transform: rotate(90deg) scale(0.6);
  pointer-events: none;
}

.volume-slider-card:not(.collapsed) + .volume-btn-toggle .volume-icon-close {
  opacity: 1;
  transform: rotate(0deg) scale(1);
  pointer-events: auto;
}

/* Floating Neomorphic Audio Slider */
.volume-slider-card {
  height: 48px;
  width: 236px;
  background: var(--card-bg);
  backdrop-filter: blur(15px);
  -webkit-backdrop-filter: blur(15px);
  border: var(--btn-border);
  border-radius: 24px;
  box-shadow: var(--neo-shadow-out);
  display: flex;
  align-items: center;
  padding: 0 12px;
  opacity: 1;
  transform: translateZ(0);
  margin-right: 0;
  overflow: hidden;
  will-change: width, opacity, margin-right;
  transition: 
    width 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    opacity 0.3s cubic-bezier(0.16, 1, 0.3, 1),
    padding 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    margin-right 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    border-color 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    box-shadow 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.volume-slider-inner {
  display: flex;
  align-items: center;
  gap: 12px;
  width: 212px;
  flex-shrink: 0;
}

.volume-slider-card.collapsed {
  width: 0;
  opacity: 0;
  padding: 0;
  margin-right: -16px; /* offsets flex gap when collapsed */
  border-color: transparent;
  box-shadow: none;
  pointer-events: none;
}

.volume-btn-mute,
.volume-btn-close {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-shrink: 0;
  transition: color 0.2s ease, background-color 0.2s ease, transform 0.2s ease;
  outline: none;
}

.volume-btn-mute:hover,
.volume-btn-close:hover {
  background: var(--volume-btn-hover-bg);
  color: var(--text-primary);
}

.volume-btn-mute svg,
.volume-btn-close svg {
  width: 16px;
  height: 16px;
  fill: currentColor;
}

.volume-slider-card input[type="range"] {
  flex-grow: 1;
}

#volume-percentage {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-primary);
  font-variant-numeric: tabular-nums;
  font-variation-settings: 'wght' 600, 'ROND' 100;
  transition: color 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  width: 32px;
  text-align: center;
  flex-shrink: 0;
  line-height: 1;
  /* Shift slightly up to compensate for font baseline layout rendering */
  transform: translateY(-1px);
}

/* Custom Neomorphic Slider Range Track */
input[type="range"] {
  -webkit-appearance: none;
  width: 100%;
  height: 6px;
  border-radius: 3px;
  background: var(--slider-track-bg);
  box-shadow: inset 1px 1px 3px rgba(0, 0, 0, 0.1);
  outline: none;
  cursor: pointer;
  transition: background-color 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Chrome/Safari Thumb */
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  background: var(--slider-thumb-bg);
  border: 2px solid var(--accent-blue);
  box-shadow: var(--neo-shadow-out);
  transition: all 0.15s cubic-bezier(0.16, 1, 0.3, 1), border-color 0.4s cubic-bezier(0.16, 1, 0.3, 1), background-color 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

input[type="range"]::-webkit-slider-thumb:hover {
  background: var(--accent-blue);
  border-color: #ffffff;
  transform: scale(1.2);
}

/* Firefox Thumb */
input[type="range"]::-moz-range-thumb {
  width: 15px;
  height: 15px;
  border-radius: 50%;
  background: var(--slider-thumb-bg);
  border: 2px solid var(--accent-blue);
  box-shadow: var(--neo-shadow-out);
  transition: all 0.15s cubic-bezier(0.16, 1, 0.3, 1), border-color 0.4s cubic-bezier(0.16, 1, 0.3, 1), background-color 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  cursor: pointer;
}

input[type="range"]::-moz-range-thumb:hover {
  background: var(--accent-blue);
  border-color: #ffffff;
  transform: scale(1.2);
}

/* Mobile Performance Optimizations (eliminates lag, thermal throttling & frame drops) */
@media (max-width: 768px) {
  .video-background-container video {
    filter: blur(2px) !important;
    will-change: auto;
  }

  .profile-card {
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    will-change: auto;
  }

  .control-btn,
  .volume-slider-card {
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
  }

  .social-btn {
    will-change: auto;
  }
}

/* Mobile Responsiveness styling */
@media (max-width: 480px) {
  body {
    align-items: flex-start;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
  }

  .container {
    align-items: flex-start;
    padding-top: 100px;
    padding-bottom: 100px;
  }

  .controls-container-top {
    top: 16px;
    right: 16px;
    gap: 12px;
  }

  .control-btn {
    width: 44px;
    height: 44px;
  }

  .volume-slider-card {
    height: 44px;
    width: 206px;
    border-radius: 22px;
    padding: 0 8px;
  }

  .volume-slider-card.collapsed {
    width: 0;
    padding: 0;
    margin-right: -12px; /* offsets mobile flex gap when collapsed */
  }

  .volume-slider-inner {
    width: 190px;
    gap: 8px;
  }

  .volume-btn-mute,
  .volume-btn-close {
    width: 24px;
    height: 24px;
  }

  .volume-btn-mute svg,
  .volume-btn-close svg {
    width: 14px;
    height: 14px;
  }
}

@media (max-width: 400px) {
  .profile-card {
    padding: 32px 20px;
    border-radius: 28px;
  }
  
  .user-name {
    font-size: 1.8rem;
  }
  
  .social-grid {
    gap: 12px;
  }
  
  .social-btn {
    border-radius: 20px;
  }
  
  .social-btn svg {
    width: 24px;
    height: 24px;
  }
}

/* =========================================
   CLICK TO ENTER OVERLAY
   ========================================= */
.enter-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 9999;
  background-color: var(--bg-color);
  display: flex;
  justify-content: center;
  align-items: center;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1), visibility 0.8s;
}

.enter-overlay::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--overlay-bg);
  z-index: -1;
  transition: background 0.4s ease;
}

.enter-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  animation: enterContentLoad 1.2s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes enterContentLoad {
  from {
    transform: scale(0.95);
  }
  to {
    transform: scale(1);
  }
}

@keyframes enterTextFadeIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.enter-btn {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 36px;
  font-family: inherit;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
  background: var(--card-bg);
  border: var(--btn-border);
  border-radius: 50px;
  cursor: pointer;
  box-shadow: var(--neo-shadow-out);
  transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  opacity: 0;
  transform: translateY(20px);
  animation: enterTextFadeIn 0.8s cubic-bezier(0.16, 1, 0.3, 1) 0.4s forwards;
}

.enter-btn:hover {
  box-shadow: var(--neo-shadow-hover);
  transform: translateY(-2px);
  color: var(--accent-blue);
}

.enter-btn:active {
  box-shadow: var(--neo-shadow-in);
  transform: translateY(1px);
}

.enter-arrow {
  width: 20px;
  height: 20px;
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.enter-btn:hover .enter-arrow {
  transform: translateX(4px);
}

.enter-overlay.fade-out {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

/* =========================================
   CINEMATIC GRAIN FILTER
   ========================================= */
.grain-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 2; /* above video (0) and overlay gradient (1) */
  overflow: hidden;
  pointer-events: none;
  opacity: 0.045; /* subtle texture, premium feel */
}

.grain-overlay::after {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
  animation: grainNoise 1s steps(10) infinite;
}

@keyframes grainNoise {
  0%, 100% { transform:translate(0, 0); }
  10% { transform:translate(-5%, -10%); }
  20% { transform:translate(-15%, 5%); }
  30% { transform:translate(7%, -25%); }
  40% { transform:translate(-5%, 25%); }
  50% { transform:translate(-15%, 10%); }
  60% { transform:translate(15%, 0%); }
  70% { transform:translate(0%, 15%); }
  80% { transform:translate(3%, 35%); }
  90% { transform:translate(-10%, 10%); }
}

/* Disable expensive SVG noise re-rasterization on mobile/touch screens to ensure smooth 60fps */
@media (max-width: 768px), (hover: none) {
  .grain-overlay {
    display: none !important;
  }
}