/**
 * Base Styles - CSS Variables, Reset, and Typography
 * Dark theme with #dc2626 (red-600) accent
 */

/* ========================================
   CSS Custom Properties (Design Tokens)
   ======================================== */
:root {
  /* Accent Color */
  --accent-color: #dc2626;
  --accent-color-light: #ef4444;
  --accent-color-dark: #b91c1c;
  --accent-color-rgb: 220, 38, 38;

  /* Background Colors */
  --bg-primary: #0a0a0a;
  --bg-secondary: #111111;
  --bg-tertiary: #1a1a1a;
  --bg-elevated: #222222;
  --bg-overlay: rgba(0, 0, 0, 0.8);

  /* Text Colors */
  --text-primary: #ffffff;
  --text-secondary: #a1a1aa;
  --text-tertiary: #71717a;
  --text-muted: #52525b;

  /* Border Colors */
  --border-color: #27272a;
  --border-color-light: #3f3f46;
  --border-color-accent: rgba(var(--accent-color-rgb), 0.5);

  /* Skeleton Colors */
  --skeleton-base: #27272a;
  --skeleton-highlight: #3f3f46;

  /* Typography */
  --font-family-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-family-mono: 'JetBrains Mono', 'Fira Code', Consolas, Monaco, 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;
  --text-6xl: 3.75rem;

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

  /* Line Heights */
  --leading-tight: 1.25;
  --leading-snug: 1.375;
  --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 rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -1px rgba(0, 0, 0, 0.2);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5), 0 4px 6px -2px rgba(0, 0, 0, 0.3);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.5), 0 10px 10px -5px rgba(0, 0, 0, 0.3);
  --shadow-glow: 0 0 20px rgba(var(--accent-color-rgb), 0.3);

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

  /* Z-Index Scale */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-fixed: 300;
  --z-modal-backdrop: 400;
  --z-modal: 500;
  --z-popover: 600;
  --z-tooltip: 700;

  /* Layout */
  --max-width: 1280px;
  --header-height: 64px;
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family-sans);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--text-primary);
  background-color: var(--bg-primary);
  min-height: 100vh;
}

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

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

button {
  cursor: pointer;
  background: none;
  border: none;
}

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

ul,
ol {
  list-style: none;
}

table {
  border-collapse: collapse;
  border-spacing: 0;
}

/* Remove default details marker */
details > summary {
  list-style: none;
}

details > summary::-webkit-details-marker {
  display: none;
}

/* ========================================
   Typography
   ======================================== */
h1, h2, h3, h4, h5, h6 {
  font-weight: var(--font-bold);
  line-height: var(--leading-tight);
  color: var(--text-primary);
}

h1 {
  font-size: var(--text-5xl);
  letter-spacing: -0.02em;
}

h2 {
  font-size: var(--text-3xl);
  letter-spacing: -0.01em;
}

h3 {
  font-size: var(--text-2xl);
}

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

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

h6 {
  font-size: var(--text-base);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

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

code,
kbd,
samp,
pre {
  font-family: var(--font-family-mono);
  font-size: 0.9em;
}

code {
  background-color: var(--bg-tertiary);
  padding: 0.2em 0.4em;
  border-radius: var(--radius-sm);
  color: var(--accent-color-light);
}

pre {
  background-color: var(--bg-secondary);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  overflow-x: auto;
  border: 1px solid var(--border-color);
}

pre code {
  background: none;
  padding: 0;
  color: inherit;
}

/* Selection */
::selection {
  background-color: rgba(var(--accent-color-rgb), 0.3);
  color: var(--text-primary);
}

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

/* Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
  background: var(--border-color-light);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* ========================================
   Utility Classes
   ======================================== */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

@media (min-width: 640px) {
  .container {
    padding: 0 var(--space-6);
  }
}

@media (min-width: 1024px) {
  .container {
    padding: 0 var(--space-8);
  }
}

/* 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;
}

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