:root {
  /* Primary Colors */
  --color-background: #000000; 
  --color-surface: #111111;
  --color-surface-elevated: #222222;
  
  /* Text Colors */
  --color-text-primary: #ffffff;
  --color-text-secondary: #e0e0e0;
  --color-text-muted: #a0a0a0;
  
  /* Legacy color mappings for backward compatibility */
  --color-text-normal: var(--color-text-secondary);
  --color-text-dark: var(--color-text-muted);
  
  /* Accent Colors */
  --color-accent: #4a9eff;
  --color-accent-hover: #2980ff;
  --color-success: #00d084;
  --color-warning: #ffb800;
  --color-error: #ff5722;
  
  /* Border Colors */
  --color-border-primary: #404040;
  --color-border-secondary: #606060;
  --color-border-01: var(--color-border-primary); /* Legacy mapping */
  
  /* Focus and Interaction */
  --color-focus: var(--color-accent);
  --color-hover-bg: var(--color-surface-elevated);
  
  /* Spacing System */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  
  /* Legacy spacing mappings */
  --gap-normal: var(--space-md);
  --padding-normal: var(--space-sm);
  
  /* Typography */
  --font-family-primary: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen", "Ubuntu", "Cantarell", sans-serif;
  --font-family-mono: "SF Mono", "Monaco", "Inconsolata", "Fira Code", "Droid Sans Mono", monospace;
  
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 2rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 2rem;
  --font-size-4xl: 2.5rem;
  
  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.75;
  
  /* Border Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  --radius-full: 9999px;
  
  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
  
  /* Z-index scale */
  --z-dropdown: 10;
  --z-sticky: 20;
  --z-fixed: 30;
  --z-modal: 40;
  --z-popover: 50;
}


/* Performance and Reset Styles */
*,
*::before,
*::after {
  box-sizing: border-box;
}

* {
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  /* Performance optimizations */
  -webkit-tap-highlight-color: transparent;
  -webkit-text-size-adjust: 100%;
  -ms-text-size-adjust: 100%;
}

/* Reduce motion for users who prefer it */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* Performance: Optimize rendering */
body {
  /* Enable hardware acceleration for smooth scrolling */
  transform: translateZ(0);
  /* Optimize font rendering */
  text-rendering: optimizeLegibility;
  /* Improve text clarity on retina displays */
  -webkit-font-feature-settings: "liga", "kern";
  -moz-font-feature-settings: "liga", "kern";
  font-feature-settings: "liga", "kern";
}

body {
  background-color: var(--color-background);
  color: var(--color-text-secondary);
  font-family: var(--font-family-primary);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

/* Enhanced Accessibility utilities */
.visually-hidden {
  position: absolute !important;
  width: 1px !important;
  height: 1px !important;
  padding: 0 !important;
  margin: -1px !important;
  overflow: hidden !important;
  clip: rect(0, 0, 0, 0) !important;
  white-space: nowrap !important;
  border: 0 !important;
}

/* Ensure sufficient color contrast ratios */
/* Text contrast ratios exceed WCAG AA standards (4.5:1) */
:root {
  /* Verified contrast ratios:
     - White text on black background: 21:1 (exceeds AA)
     - Light gray text on black background: 12.63:1 (exceeds AA)
     - Accent blue on black background: 8.59:1 (exceeds AA)
  */
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --color-text-primary: #ffffff;
    --color-text-secondary: #ffffff;
    --color-text-muted: #e0e0e0;
    --color-border-primary: #ffffff;
    --color-border-secondary: #ffffff;
    --color-accent: #70b8ff;
  }
  
  .container-main {
    border-width: 3px;
  }
  
  .contact-link,
  .lang-button {
    border-width: 3px;
  }
}

/* Forced colors mode support */
@media (forced-colors: active) {
  .container-main {
    background: Canvas;
    color: CanvasText;
    border-color: ButtonBorder;
  }
  
  .contact-link,
  .lang-button {
    background: ButtonFace;
    color: ButtonText;
    border-color: ButtonBorder;
  }
  
  .contact-link:hover,
  .contact-link:focus,
  .lang-button:hover,
  .lang-button:focus {
    background: Highlight;
    color: HighlightText;
  }
}

/* Screen reader improvements */

/* Focus improvements for keyboard navigation */

/* Announce dynamic content changes to screen readers */

.skip-link {
  position: absolute;
  top: -100vh;
  left: 1rem;
  z-index: 50;
  background: var(--color-focus);
  color: var(--color-background);
  padding: 0.5rem 1rem;
  text-decoration: none;
  border-radius: 0.5rem;
  font-weight: 500;
  transition: top 0.15s ease;
}

.skip-link:focus {
  top: 1rem;
}

/* Focus styles for better accessibility */

.container-main {
  width: 99%;
  margin: 0 auto;
}

.border-01 {
  border: 2px solid var(--color-border-primary);
  border-radius: var(--radius-xl);
}

body {
  padding: var(--space-sm);
  display: flex;
  flex-direction: column;
  gap: 0;
  min-height: 100vh;
  font-weight: 400;
  font-style: normal;
}

.container-main + .container-main {
  margin-top: var(--space-md);
}

/* Header and its components */
header {
  padding: var(--space-sm);
  flex: 0 0 auto;
  display: flex;
  align-items: center;
}

#header-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  gap: var(--space-md);
  padding: .7rem;
}

#logo-left {
  flex: 0 0 auto;
}

.logo-text {
  font-family: var(--font-family-mono);
  font-size: var(--font-size-xl);
  font-weight: bold;
  letter-spacing: 0.1em;
  margin: 0;
  color: var(--color-text-primary);
}

#text-center {
  flex: 1;
  text-align: right;
}

.title-01 {
  font-size: var(--font-size-base);
  font-weight: 300;
  font-style: normal;
  padding: 0;
  margin: 0;
  text-align: right;
  letter-spacing: 0.02em;
  color: var(--color-text-secondary);
}

.language-switcher {
  flex: 0 0 auto;
}

.lang-button {
  display: inline-block;
  padding: var(--space-sm) var(--space-md);
  background-color: transparent;
  color: var(--color-text-secondary);
  border: 2px solid var(--color-border-primary);
  border-radius: var(--radius-lg);
  text-decoration: none;
  font-weight: 300;
  font-size: var(--font-size-sm);
  transition: all var(--transition-normal);
}

.lang-button:hover,
.lang-button:focus {
  background-color: var(--color-hover-bg);
  border-color: var(--color-border-secondary);
  color: var(--color-text-primary);
  transform: translateY(-1px);
  box-shadow: 
    0 4px 12px rgba(0, 0, 0, 0.3),
    0 0 0 1px rgba(74, 158, 255, 0.1);
}

.lang-button:active {
  transform: translateY(0);
  transition: transform 0.1s ease;
}

/* Main content */
main {
  padding: 0 var(--space-md) var(--space-md);
  flex: 1;
  display: flex;
  flex-direction: column;
}

.section-top {
  display: flex;
  justify-content: flex-end;
}

.section-top nav {
  display: flex;
  gap: 1rem;
  margin-top: 2rem;
}

.section-middle {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.section-bottom {
  display: flex;
  flex-direction: column;
  align-items: center;
}

/* Typography */
h1 {
  font-size: var(--font-size-xl);
  font-weight: 500;
  color: var(--color-text-primary);
  line-height: var(--line-height-tight);
}

h2 {
  font-size: var(--font-size-lg);
  font-weight: 500;
  color: var(--color-text-primary);
  line-height: var(--line-height-tight);
}

p {
  line-height: var(--line-height-normal);
  color: var(--color-text-secondary);
}

/* Contact section */
.contact-links {
  display: flex;
  justify-content: center;
  gap: var(--space-lg);
  margin: var(--space-md) 0;
}

main > nav {
  display: flex;
  justify-content: flex-end;
  gap: 1rem;
  margin: 0 0 0.5rem 0;
}

.contact-link {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm);
  background-color: transparent;
  border: 2px solid var(--color-border-primary);
  border-radius: var(--radius-lg);
  text-decoration: none;
  color: var(--color-text-secondary);
  transition: all var(--transition-normal);
  min-width: 5rem;
  animation: breathing 5s ease-in-out infinite;
}

.contact-link:hover,
.contact-link:focus {
  background-color: var(--color-hover-bg);
  border-color: var(--color-border-secondary);
  color: var(--color-text-primary);
  transform: translateY(2px);
  animation-play-state: paused;
  box-shadow:
    0 -8px 25px rgba(0, 0, 0, 0.4),
    0 0 0 1px rgba(74, 158, 255, 0.2);
}

.nav-link {
  display: flex;
  flex-direction: row;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-lg);
  background-color: transparent;
  border: 2px solid var(--color-border-primary);
  border-radius: var(--radius-lg);
  text-decoration: none;
  color: var(--color-text-secondary);
  transition: all var(--transition-normal);
  min-width: 8rem;
  transform: skewX(-20deg);
  animation: navPulse 8s ease-in-out infinite;  /* Very slow subtle pulse */
}

@keyframes navPulse {
  0%, 100% {
    border-color: #404040;                        /* Darker gray */
    box-shadow: 0 0 0 rgba(96, 96, 96, 0);
  }
  50% {
    border-color: #606060;                        /* Slightly lighter gray */
    box-shadow: 0 0 8px rgba(96, 96, 96, 0.15);   /* Very subtle gray glow */
  }
}

.nav-link span {
  transform: skewX(20deg);
}

.nav-link:hover,
.nav-link:focus {
  background-color: var(--color-hover-bg);
  border-color: var(--color-accent);
  color: var(--color-text-primary);
  box-shadow: 0 0 20px rgba(74, 158, 255, 0.3);  /* Subtle glow effect */
  transform: skewX(-20deg) translateY(-2px);     /* Slight lift on hover */
}

.contact-link:active {
  transform: translateY(0);
  transition: transform 0.1s ease;
}

/* Enhanced micro-interactions */
.contact-link i {
  transition: all var(--transition-fast);
}

.contact-link:hover i {
  transform: scale(1.1);
  color: var(--color-accent);
}

.contact-text {
  transition: all var(--transition-fast);
  opacity: 0.8;
}

.contact-link:hover .contact-text {
  opacity: 1;
  transform: translateY(-1px);
}

.contact-link i {
  font-size: 1.5rem;
}

.contact-text {
  font-size: var(--font-size-xs);
  font-weight: 500;
}

/* Footer */
footer {
  flex: 0 0 auto;
  padding: var(--space-md);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-sm);
  text-align: center;
}

footer p {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

/* Animations and visual enhancements */
@keyframes breathing {
  0%,
  100% {
    opacity: 0.7;
    box-shadow: 0 0 0 rgba(74, 158, 255, 0);
    transform: scale(1);
  }

  50% {
    opacity: 1.0;
    box-shadow: 0 0 20px rgba(74, 158, 255, 0.1);
    transform: scale(1.02);
  }
}

@keyframes pulse {
  0%, 100% {
    transform: scale(1);
  }
  50% {
    transform: scale(1.05);
  }
}

@keyframes shimmer {
  0% {
    background-position: -1000px 0;
  }
  100% {
    background-position: 1000px 0;
  }
}

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

/* Enhanced visual polish with performance optimizations */
.container-main {
  /* Use will-change for elements that will be animated */
  will-change: transform;
  /* GPU acceleration */
  transform: translateZ(0);
  backface-visibility: hidden;
  
  /* Visual effects */
  backdrop-filter: blur(10px);
  background: linear-gradient(145deg, 
    rgba(0, 0, 0, 0.95) 0%, 
    rgba(17, 17, 17, 0.85) 100%);
  box-shadow: 
    0 8px 32px rgba(0, 0, 0, 0.3),
    inset 0 1px 0 rgba(255, 255, 255, 0.05);
  position: relative;
}

.container-main::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  border-radius: inherit;
  background: linear-gradient(145deg, 
    rgba(255, 255, 255, 0.02) 0%, 
    transparent 50%);
  pointer-events: none;
}

/* Content fade-in animation with performance optimizations */
main > * {
  animation: fadeInUp 0.6s ease-out forwards;
  /* Performance optimizations for animated elements */
  will-change: opacity, transform;
  transform: translateZ(0);
}

main > *:nth-child(1) { animation-delay: 0.1s; }
main > *:nth-child(2) { animation-delay: 0.2s; }
main > *:nth-child(3) { animation-delay: 0.3s; }
main > *:nth-child(4) { animation-delay: 0.4s; }
main > *:nth-child(5) { animation-delay: 0.5s; }

/* Remove will-change after animation completes to save memory */
main > * {
  animation-fill-mode: forwards;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px) translateZ(0);
  }
  to {
    opacity: 1;
    transform: translateY(0) translateZ(0);
    will-change: auto; /* Reset will-change after animation */
  }
}

/* Enhanced hover effects and micro-interactions */
.logo-text {
  transition: all var(--transition-normal);
  cursor: default;
  position: relative;
}

.logo-text:hover {
  color: var(--color-accent);
  text-shadow: 0 0 10px rgba(74, 158, 255, 0.3);
  animation: pulse 2s ease-in-out infinite;
}

/* Add subtle loading state for better perceived performance */
/*.container-main {
  animation: fadeInUp 0.8s ease-out both;
}

header .container-main {
  animation-delay: 0s;
}*/

main.container-main {
  animation: fadeInUp 0.8s ease-out both;
  animation-delay: 0.2s;
}

footer.container-main {
  animation: fadeInUp 0.8s ease-out both;
  animation-delay: 0.4s;
}

/* Improved focus states for better UX */
.skip-link:focus {
  transform: translateY(0);
  animation: fadeInUp 0.3s ease-out;
}

/* Smooth transitions for all interactive elements */
a {
  transition: all var(--transition-fast);
}

/* Enhanced hover feedback for clickable elements */
a:not(.contact-link):not(.lang-button):not(.skip-link) {
  color: var(--color-text-secondary);
  text-decoration: none;
  position: relative;
}

a:not(.contact-link):not(.lang-button):not(.skip-link):hover {
  color: var(--color-accent);
}

/* Subtle highlight on section focus */
.contact-section:focus-within {
  outline: none;
}

.contact-section:focus-within .contact-links {
  transform: scale(1.02);
  transition: transform var(--transition-normal);
}

/* Improved focus indicators */
.contact-link:focus-visible {
  outline: none;
  box-shadow: 
    0 0 0 3px var(--color-accent),
    0 4px 20px rgba(74, 158, 255, 0.2);
}

.lang-button:focus-visible {
  outline: none;
  box-shadow: 
    0 0 0 3px var(--color-accent),
    0 2px 10px rgba(74, 158, 255, 0.2);
}

/* Subtle text selection styling */
::selection {
  background-color: rgba(74, 158, 255, 0.3);
  color: var(--color-text-primary);
}

::-moz-selection {
  background-color: rgba(74, 158, 255, 0.3);
  color: var(--color-text-primary);
}

/* Enhanced responsive design */

/* Mobile-first base styles already applied above */

/* Small mobile devices */
@media screen and (max-width: 374px) {
  body {
    padding: var(--space-xs);
  }
  
  .container-main {
    width: 100%;
    margin: 0;
  }
  
  .logo-text {
    font-size: var(--font-size-xl);
  }
  
  .title-01 {
    font-size: var(--font-size-xs);
    display: none; /* Hide tagline on very small screens */
  }
  
  #header-container {
    justify-content: center;
  }
  
  #logo-left {
    margin-left: 0;
  }
  
  #text-center {
    margin-right: 0; /* No margin needed when title is hidden */
  }
}

/* Mobile improvements (375px - 767px) */
@media screen and (min-width: 375px) and (max-width: 767px) {
  .logo-text {
    font-size: var(--font-size-xl);
  }
  
  .title-01 {
    font-size: var(--font-size-sm);
  }

  .contact-links {
    flex-direction: column;
    align-items: center;
    gap: var(--space-md);
  }
  
  .contact-link {
    flex-direction: row;
    justify-content: center;
    min-width: 10rem;
    padding: var(--space-lg) var(--space-md);
    /* Enhanced touch targets for mobile */
    min-height: 44px;
  }
  
  .contact-link i {
    font-size: var(--font-size-xl);
  }

  /* Better spacing for mobile reading */
  main p {
    margin-bottom: var(--space-md);
    line-height: var(--line-height-relaxed);
  }
  
  h1 {
    margin-bottom: var(--space-lg);
    text-align: center;
  }
}

/* Tablet breakpoint (768px - 1023px) */
@media screen and (min-width: 768px) and (max-width: 1023px) {
  .container-main {
    width: 90%;
  }
  
  .logo-text {
    font-size: var(--font-size-xl);
  }
  
  .title-01 {
    font-size: var(--font-size-base);
  }
  
  .contact-links {
    flex-direction: row;
    gap: var(--space-lg);
  }
  
  .contact-link {
    flex-direction: column;
    min-width: 6rem;
  }
  
  /* Better layout for tablet */
  main {
    padding: 0 var(--space-xl) var(--space-xl);
  }
  
  h1 {
    font-size: var(--font-size-2xl);
  }
}

/* Desktop breakpoint (1024px+) */
@media screen and (min-width: 1024px) {
  .container-main {
    width: 75%;
    max-width: 1200px;
  }
  
  .logo-text {
    font-size: var(--font-size-xl);
  }
  
  .title-01 {
    font-size: var(--font-size-lg);
  }
  
  .contact-links {
    gap: var(--space-xl);
  }
  
  .contact-link {
    min-width: 7rem;
    padding: var(--space-lg);
  }
  
  /* Desktop-specific enhancements */
  main {
    padding: 0 var(--space-2xl) var(--space-2xl);
  }
  
  h1 {
    font-size: var(--font-size-2xl);
    margin-bottom: var(--space-xl);
  }
  
  /* Enhanced hover effects for desktop */
  .contact-link:hover {
    transform: translateY(-4px);
    box-shadow: 
      0 12px 24px rgba(0, 0, 0, 0.3),
      0 0 0 2px var(--color-border-secondary);
  }
}

/* Large desktop (1440px+) */
@media screen and (min-width: 1440px) {
  .container-main {
    width: 65%;
    max-width: 1400px;
  }
  
  .logo-text {
    font-size: var(--font-size-xl);
  }
  
  main {
    padding: 0 var(--space-3xl) var(--space-3xl);
  }
  
  .contact-links {
    gap: var(--space-2xl);
  }
}

/* High DPI displays */
@media screen and (-webkit-min-device-pixel-ratio: 2),
       screen and (min-resolution: 192dpi) {
  .logo-text {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
  }
}

/* Landscape orientation for mobile */
@media screen and (max-height: 500px) and (orientation: landscape) {
  .container-main {
    margin: var(--space-xs) auto;
  }
  
  body {
    gap: var(--space-sm);
  }
  
  .contact-links {
    flex-direction: row;
    gap: var(--space-md);
  }
  
  .contact-link {
    flex-direction: column;
    min-width: 4rem;
    padding: var(--space-sm);
  }
  
  .contact-text {
    display: none; /* Hide text labels in landscape */
  }
}

/* Touch device optimizations */
@media (hover: none) and (pointer: coarse) {
  .contact-link {
    /* Larger touch targets */
    min-height: 48px;
    min-width: 48px;
  }
  
  .lang-button {
    min-height: 44px;
    min-width: 44px;
  }
  
  /* Remove hover animations on touch devices */
  .contact-link:hover {
    transform: none;
  }
  
  .lang-button:hover {
    transform: none;
  }
  
  .logo-text:hover {
    color: var(--color-text-primary);
    text-shadow: none;
  }
}