*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --color-bg-primary: #0f1419;
  --color-bg-card: #1a1f2e;
  --color-bg-hover: #252b3b;
  --color-accent: #14b8a6;
  --color-accent-hover: #0d9488;
  --color-text-primary: #e2e8f0;
  --color-text-secondary: #94a3b8;
  --color-text-muted: #64748b;
  --color-success: #10b981;
  --color-error: #ef4444;

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen", "Ubuntu", "Cantarell", sans-serif;
  --font-mono: "SF Mono", "Monaco", "Inconsolata", "Fira Code", monospace;

  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 0.75rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;

  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;

  /* 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, 0.3);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.4);

  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-base: 250ms ease-in-out;
  --transition-slow: 350ms ease-in-out;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background: var(--color-bg-primary);
  color: var(--color-text-primary);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  padding: 0;
}

/* Navigation Bar */
.navbar {
  background: var(--color-bg-card);
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  padding: var(--spacing-md) 0;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-md);
}

.navbar-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.navbar-logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-accent);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.navbar-logo:hover {
  color: var(--color-accent-hover);
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: var(--spacing-md);
  margin: 0;
  padding: 0;
}

.nav-item {
  margin: 0;
}

.nav-link {
  color: var(--color-text-secondary);
  text-decoration: none;
  font-weight: 500;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.nav-link:hover {
  color: var(--color-text-primary);
  background: var(--color-bg-hover);
}

.nav-link.active {
  color: var(--color-accent);
  background: rgba(20, 184, 166, 0.1);
}

.nav-link:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* Container & Layout */
.container {
  width: 100%;
  max-width: 900px;
  margin: 0 auto;
  padding: var(--spacing-lg);
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Mobile adjustments */
@media (max-width: 767px) {
  .navbar-container {
    padding: 0 var(--spacing-md);
  }

  .navbar-logo {
    font-size: 1.25rem;
  }

  .nav-menu {
    gap: var(--spacing-xs);
  }

  .nav-link {
    font-size: 0.9rem;
    padding: var(--spacing-xs) var(--spacing-sm);
  }

  .container {
    padding: var(--spacing-md);
  }

  body {
    padding: 0;
  }
}

/* Accessibility & Focus Styles */
*:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

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

/* High contrast mode support */
@media (prefers-contrast: high) {
  .profile-card {
    border: 2px solid var(--color-text-primary);
  }

  .social-link,
  .info-item {
    border: 2px solid var(--color-text-secondary);
  }
}