/* Base CSS - Reset, Typography, CSS Variables */

/* CSS Variables */
:root {
  /* Colors - Light theme with strong contrast */
  --color-bg: #fafafa;
  --color-bg-elevated: #ffffff;
  --color-bg-subtle: #f0f0f2;
  --color-text: #0a0a0b;
  --color-text-muted: #52525b;
  --color-text-subtle: #71717a;
  --color-border: #d4d4d8;
  --color-border-subtle: #e4e4e7;

  /* Accent colors for clusters */
  --color-simulation: #0891b2;      /* Cyan */
  --color-dashboards: #7c3aed;      /* Violet */
  --color-ai-first: #059669;        /* Emerald */
  --color-ai-cad: #ea580c;          /* Orange */
  --color-backend: #4f46e5;         /* Indigo */
  --color-utilities: #db2777;       /* Pink */
  --color-teaching: #0284c7;        /* Sky */
  --color-research: #ca8a04;        /* Yellow */

  /* Primary accent */
  --color-primary: #0891b2;
  --color-primary-hover: #0e7490;

  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;

  /* Font sizes */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;

  /* Font weights */
  --font-normal: 400;
  --font-medium: 500;
  --font-semibold: 600;
  --font-bold: 700;

  /* Line heights */
  --leading-tight: 1.25;
  --leading-normal: 1.5;
  --leading-relaxed: 1.625;

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Border radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.375rem;
  --radius-lg: 0.5rem;
  --radius-xl: 0.75rem;
  --radius-2xl: 1rem;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 200ms ease;
  --transition-slow: 300ms ease;

  /* Z-index */
  --z-base: 0;
  --z-elevated: 10;
  --z-sticky: 500;
  --z-modal: 1000;
  --z-tooltip: 1100;
}

/* Dark theme */
@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #09090b;
    --color-bg-elevated: #18181b;
    --color-bg-subtle: #27272a;
    --color-text: #fafafa;
    --color-text-muted: #a1a1aa;
    --color-text-subtle: #71717a;
    --color-border: #3f3f46;
    --color-border-subtle: #27272a;
  }
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  overflow-x: hidden;
  max-width: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  /* Subtle dot grid background for visual anchoring */
  background-image: radial-gradient(circle, var(--color-border) 1px, transparent 1px);
  background-size: 24px 24px;
  overflow-x: hidden;
  max-width: 100%;
}

img, picture, video, canvas, svg {
  display: block;
  max-width: 100%;
}

input, button, textarea, select {
  font: inherit;
}

p, h1, h2, h3, h4, h5, h6 {
  overflow-wrap: break-word;
}

a {
  color: inherit;
  text-decoration: none;
}

ul, ol {
  list-style: none;
}

/* Typography utilities */
.text-xs { font-size: var(--text-xs); }
.text-sm { font-size: var(--text-sm); }
.text-base { font-size: var(--text-base); }
.text-lg { font-size: var(--text-lg); }
.text-xl { font-size: var(--text-xl); }
.text-2xl { font-size: var(--text-2xl); }
.text-3xl { font-size: var(--text-3xl); }
.text-4xl { font-size: var(--text-4xl); }
.text-5xl { font-size: var(--text-5xl); }

.font-normal { font-weight: var(--font-normal); }
.font-medium { font-weight: var(--font-medium); }
.font-semibold { font-weight: var(--font-semibold); }
.font-bold { font-weight: var(--font-bold); }

.text-muted { color: var(--color-text-muted); }
.text-subtle { color: var(--color-text-subtle); }

.font-mono { font-family: var(--font-mono); }

/* Focus styles */
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* Selection */
::selection {
  background-color: var(--color-primary);
  color: white;
}