/* Design Tokens - Dark Monochrome Portfolio */

:root {
  /* Colors */
  --color-black: #0B0B0D;
  --color-dark-grey: #151518;
  --color-mid-grey: #222226;
  --color-light-grey: #9A9AA3;
  --color-off-white: #F3F3F5;
  --color-white: #FFFFFF;
  
  /* Typography */
  --font-heading: 'Space Grotesk', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  
  /* Font Sizes */
  --text-xs: 0.75rem;    /* 12px */
  --text-sm: 0.875rem;   /* 14px */
  --text-base: 1rem;     /* 16px */
  --text-lg: 1.125rem;   /* 18px */
  --text-xl: 1.25rem;    /* 20px */
  --text-2xl: 1.5rem;    /* 24px */
  --text-3xl: 1.875rem;  /* 30px */
  --text-4xl: 2.25rem;   /* 36px */
  --text-5xl: 3rem;      /* 48px */
  --text-6xl: 3.75rem;   /* 60px */
  
  /* Font Weights */
  --font-regular: 400;
  --font-medium: 500;
  --font-semibold: 600;
  --font-bold: 700;
  
  /* Spacing */
  --space-1: 0.25rem;    /* 4px */
  --space-2: 0.5rem;     /* 8px */
  --space-3: 0.75rem;    /* 12px */
  --space-4: 1rem;       /* 16px */
  --space-5: 1.25rem;    /* 20px */
  --space-6: 1.5rem;     /* 24px */
  --space-8: 2rem;       /* 32px */
  --space-10: 2.5rem;    /* 40px */
  --space-12: 3rem;      /* 48px */
  --space-16: 4rem;      /* 64px */
  --space-20: 5rem;      /* 80px */
  --space-24: 6rem;      /* 96px */
  --space-32: 8rem;      /* 128px */
  
  /* Layout */
  --max-width: 1200px;
  --gutter: 24px;
  --section-spacing-sm: 80px;
  --section-spacing-lg: 120px;
  
  /* Borders */
  --border-radius-sm: 4px;
  --border-radius-md: 8px;
  --border-radius-lg: 12px;
  --border-radius-xl: 16px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(11, 11, 13, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(11, 11, 13, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(11, 11, 13, 0.1);
  
  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-normal: 250ms ease-in-out;
  --transition-slow: 350ms ease-in-out;
  
  /* Focus ring */
  --focus-ring: 0 0 0 2px var(--color-off-white);
}

/* Base Styles */
* {
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--font-regular);
  line-height: 1.6;
  color: var(--color-off-white);
  background-color: var(--color-black);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Typography Scale */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: var(--font-semibold);
  line-height: 1.2;
  color: var(--color-white);
  margin-top: 0;
  margin-bottom: var(--space-4);
}

h1 {
  font-size: var(--text-5xl);
}

h2 {
  font-size: var(--text-4xl);
}

h3 {
  font-size: var(--text-3xl);
}

h4 {
  font-size: var(--text-2xl);
}

h5 {
  font-size: var(--text-xl);
}

h6 {
  font-size: var(--text-lg);
}

p {
  margin-top: 0;
  margin-bottom: var(--space-4);
}

/* Links */
a {
  color: var(--color-white);
  text-decoration: underline;
  text-decoration-color: var(--color-light-grey);
  text-underline-offset: 2px;
  transition: all var(--transition-fast);
}

a:hover {
  color: var(--color-off-white);
  text-decoration-color: var(--color-off-white);
}

a:focus {
  outline: none;
  box-shadow: var(--focus-ring);
  border-radius: var(--border-radius-sm);
}

/* Focus styles for all interactive elements */
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

/* Screen reader only */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Responsive Design */
@media (max-width: 768px) {
  :root {
    --text-5xl: 2.5rem;   /* 40px */
    --text-4xl: 2rem;     /* 32px */
    --text-3xl: 1.75rem;  /* 28px */
    --gutter: 16px;
    --section-spacing-sm: 60px;
    --section-spacing-lg: 80px;
  }
}

/* Dark mode preference respect */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}