/* ============================================================
   HRHK Solutions — Global CSS
   File: assets/css/global.css
   Purpose: CSS custom properties, reset, base element styles
   ============================================================ */

/* --- CSS Custom Properties (Design Tokens) --- */
:root {
  /* Primary Colors */
  --color-primary: #0f172a;
  --color-primary-light: #1e293b;
  --color-primary-dark: #020617;
  --color-accent: #3b82f6;
  --color-accent-light: #60a5fa;
  --color-accent-dark: #2563eb;

  /* Neutral Colors */
  --color-bg: #ffffff;
  --color-bg-alt: #f8fafc;
  --color-bg-dark: #0f172a;
  --color-text: #1e293b;
  --color-text-light: #64748b;
  --color-text-inverse: #f8fafc;
  --color-border: #e2e8f0;

  /* Semantic Colors */
  --color-success: #22c55e;
  --color-warning: #f59e0b;
  --color-error: #ef4444;
  --color-info: #3b82f6;

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

  /* Type Scale */
  --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;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;

  /* Layout */
  --container-max: 1280px;
  --container-padding: var(--space-md);
  --header-height: 72px;

  /* Borders & Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;

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

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

  /* Z-Index Scale */
  --z-base: 1;
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-overlay: 300;
  --z-modal: 400;
  --z-header: 500;
}

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

html {
  font-size: 100%;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.65;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-text);
  margin-bottom: var(--space-md);
}

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-bottom: var(--space-md);
  line-height: 1.7;
}

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-accent-dark);
  text-decoration: underline;
}

/* --- Lists --- */
ul, ol {
  margin-bottom: var(--space-md);
  padding-left: var(--space-xl);
}

li {
  margin-bottom: var(--space-sm);
  line-height: 1.6;
}

/* --- Images & Media --- */
img, svg {
  max-width: 100%;
  height: auto;
  display: block;
}

/* --- Code --- */
code {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  background-color: var(--color-bg-alt);
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--radius-sm);
}

pre {
  background-color: var(--color-bg-dark);
  color: var(--color-text-inverse);
  padding: var(--space-lg);
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin-bottom: var(--space-lg);
}

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

/* --- Tables --- */
table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: var(--space-lg);
}

th, td {
  padding: var(--space-sm) var(--space-md);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

th {
  font-weight: 600;
  background-color: var(--color-bg-alt);
}

/* --- Horizontal Rule --- */
hr {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: var(--space-2xl) 0;
}

/* --- Selection --- */
::selection {
  background-color: var(--color-accent);
  color: var(--color-text-inverse);
}

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

/* --- Skip Link --- */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--color-accent);
  color: var(--color-text-inverse);
  padding: var(--space-sm) var(--space-md);
  z-index: var(--z-modal);
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: 0;
}

/* --- Utility Classes --- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

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

.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }