/**
 * Claude Resource Hub - Main Stylesheet
 * Mobile-first responsive design with 2026 CSS features
 * WCAG 2.2 Level AA compliant
 */

/* ===== CSS Custom Properties ===== */
:root {
  /* Colors - WCAG AA compliant */
  --color-primary: #2563eb;
  --color-primary-dark: #1e40af;
  --color-secondary: #7c3aed;
  --color-text: #1f2937;
  --color-text-light: #6b7280;
  --color-bg: #ffffff;
  --color-bg-alt: #f9fafb;
  --color-border: #e5e7eb;
  --color-success: #10b981;
  --color-vibe: #f59e0b;
  --color-vanilla: #3b82f6;
  
  /* Typography */
  --font-sans: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', monospace;
  
  /* Fluid typography using clamp() */
  --font-size-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --font-size-sm: clamp(0.875rem, 0.8rem + 0.375vw, 1rem);
  --font-size-base: clamp(1rem, 0.9rem + 0.5vw, 1.125rem);
  --font-size-lg: clamp(1.125rem, 1rem + 0.625vw, 1.25rem);
  --font-size-xl: clamp(1.25rem, 1.1rem + 0.75vw, 1.5rem);
  --font-size-2xl: clamp(1.5rem, 1.3rem + 1vw, 2rem);
  --font-size-3xl: clamp(1.875rem, 1.5rem + 1.875vw, 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;
  
  /* Layout */
  --container-max: 1280px;
  --content-max: 65ch;
  
  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 350ms ease;
  
  /* 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);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
}

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

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

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

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

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

h1 { font-size: var(--font-size-3xl); }
h2 { font-size: var(--font-size-2xl); }
h3 { font-size: var(--font-size-xl); }
h4 { font-size: var(--font-size-lg); }

p {
  margin-bottom: var(--space-md);
}

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

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

a:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: 2px;
}

code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background-color: var(--color-bg-alt);
  padding: 0.125rem 0.25rem;
  border-radius: 3px;
}

/* ===== Utility Classes ===== */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }

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

/* ===== Skip Link ===== */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--color-primary);
  color: white;
  padding: var(--space-sm) var(--space-md);
  z-index: 100;
  border-radius: 0 0 4px 0;
}

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

/* ===== Header ===== */
.site-header {
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: var(--space-md);
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(8px);
  background-color: rgb(255 255 255 / 0.95);
}

.site-header nav {
  max-width: var(--container-max);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  align-items: flex-start;
}

.logo {
  font-size: var(--font-size-lg);
  font-weight: 700;
  color: var(--color-text);
}

.nav-links {
  list-style: none;
  display: flex;
  gap: var(--space-lg);
  flex-wrap: wrap;
}

/* ===== Main Content ===== */
main {
  flex: 1;
  max-width: var(--container-max);
  width: 100%;
  margin: 0 auto;
  padding: var(--space-xl) var(--space-md);
}

/* ===== Hero Section ===== */
.hero {
  text-align: center;
  padding: var(--space-2xl) 0;
  margin-bottom: var(--space-2xl);
}

.hero h1 {
  margin-bottom: var(--space-md);
}

.hero-subtitle {
  font-size: var(--font-size-lg);
  color: var(--color-text-light);
  max-width: var(--content-max);
  margin: 0 auto;
}

/* ===== Search Container ===== */
.search-container {
  background-color: var(--color-bg-alt);
  border-radius: 8px;
  padding: var(--space-xl);
  margin-bottom: var(--space-2xl);
}

.search-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  margin-bottom: var(--space-lg);
}

.search-form input[type="search"] {
  width: 100%;
  padding: var(--space-md);
  font-size: var(--font-size-base);
  border: 2px solid var(--color-border);
  border-radius: 6px;
  transition: border-color var(--transition-fast);
}

.search-form input[type="search"]:focus {
  outline: none;
  border-color: var(--color-primary);
}

.search-form button {
  padding: var(--space-md) var(--space-xl);
  background-color: var(--color-primary);
  color: white;
  border: none;
  border-radius: 6px;
  font-size: var(--font-size-base);
  font-weight: 600;
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.search-form button:hover {
  background-color: var(--color-primary-dark);
}

.search-form button:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* ===== Search Filters ===== */
.search-filters {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.search-filters fieldset {
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: var(--space-md);
}

.search-filters legend {
  font-weight: 600;
  padding: 0 var(--space-sm);
}

.search-filters label {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-top: var(--space-sm);
  cursor: pointer;
}

/* ===== Code Container ===== */
.code-container {
  position: relative;
  margin: var(--space-lg) 0;
  container-type: inline-size;
}

.code-container pre {
  background-color: #1e293b;
  color: #e2e8f0;
  padding: var(--space-lg);
  border-radius: 8px;
  overflow-x: auto;
  font-size: var(--font-size-sm);
  line-height: 1.5;
}

.code-container code {
  background: none;
  padding: 0;
  color: inherit;
}

.copy-button {
  position: absolute;
  top: var(--space-sm);
  right: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  background-color: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  font-size: var(--font-size-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
  will-change: transform;
}

.copy-button:hover {
  background-color: var(--color-bg-alt);
  transform: translateY(-1px);
}

.copy-button.copied {
  background-color: var(--color-success);
  color: white;
  border-color: var(--color-success);
}

/* ===== Style Tags ===== */
.style-tag {
  display: inline-block;
  padding: var(--space-xs) var(--space-sm);
  border-radius: 4px;
  font-size: var(--font-size-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.style-vibe {
  background-color: #fef3c7;
  color: #92400e;
}

.style-vanilla {
  background-color: #dbeafe;
  color: #1e40af;
}

/* ===== Tags ===== */
.tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  margin-top: var(--space-lg);
}

.tag {
  padding: var(--space-xs) var(--space-sm);
  background-color: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  font-size: var(--font-size-sm);
  transition: all var(--transition-fast);
}

.tag:hover {
  background-color: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
  text-decoration: none;
}

/* ===== Resource Cards ===== */
.resource-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-lg);
  margin-top: var(--space-lg);
}

@media (min-width: 768px) {
  .resource-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.resource-card {
  background-color: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: var(--space-lg);
  transition: all var(--transition-base);
}

.resource-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.resource-card h3 {
  margin-bottom: var(--space-sm);
}

.card-meta {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
  margin-top: var(--space-md);
}

.language, .category {
  padding: var(--space-xs) var(--space-sm);
  background-color: var(--color-bg-alt);
  border-radius: 4px;
  font-size: var(--font-size-xs);
  font-weight: 600;
}

/* ===== Category Navigation ===== */
.category-nav {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-lg);
  margin-top: var(--space-lg);
}

@media (min-width: 768px) {
  .category-nav {
    grid-template-columns: repeat(3, 1fr);
  }
}

.category-card {
  background-color: var(--color-bg-alt);
  border: 2px solid var(--color-border);
  border-radius: 8px;
  padding: var(--space-xl);
  text-align: center;
  transition: all var(--transition-base);
  display: block;
}

.category-card:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
  text-decoration: none;
}

.category-card h3 {
  color: var(--color-text);
  margin-bottom: var(--space-sm);
}

.category-card p {
  color: var(--color-text-light);
  margin-bottom: 0;
}

/* ===== Article Styles ===== */
.snippet-header, .article-header {
  margin-bottom: var(--space-xl);
}

.snippet-meta, .article-meta {
  display: flex;
  gap: var(--space-md);
  flex-wrap: wrap;
  margin-top: var(--space-md);
}

.snippet-description {
  font-size: var(--font-size-lg);
  color: var(--color-text-light);
  margin-bottom: var(--space-xl);
}

.snippet-footer, .article-body {
  margin-top: var(--space-2xl);
}

.usage-section {
  margin-bottom: var(--space-xl);
}

/* ===== Footer ===== */
.site-footer {
  background-color: var(--color-bg-alt);
  border-top: 1px solid var(--color-border);
  padding: var(--space-xl) var(--space-md);
  margin-top: auto;
  text-align: center;
}

.site-footer nav {
  margin-top: var(--space-md);
  display: flex;
  justify-content: center;
  gap: var(--space-lg);
  flex-wrap: wrap;
}

/* ===== Responsive Breakpoints ===== */
@container (min-width: 768px) {
  .code-container pre {
    font-size: var(--font-size-base);
  }
}

@media (min-width: 768px) {
  .site-header nav {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
  
  .search-form {
    flex-direction: row;
  }
  
  .search-form input[type="search"] {
    flex: 1;
  }
  
  .search-form button {
    width: auto;
  }
  
  .search-filters {
    flex-direction: row;
  }
  
  .search-filters fieldset {
    flex: 1;
  }
}

@media (min-width: 1280px) {
  main {
    padding: var(--space-3xl) var(--space-xl);
  }
  
  .hero {
    padding: var(--space-3xl) 0;
  }
}

/* ===== Performance Optimizations ===== */
@supports (content-visibility: auto) {
  .search-results > * {
    content-visibility: auto;
    contain-intrinsic-size: 0 500px;
  }
}

/* Reduce layout shift */
img, video {
  max-width: 100%;
  height: auto;
  aspect-ratio: attr(width) / attr(height);
}

/* Font loading optimization */
@font-face {
  font-family: 'System';
  font-display: swap;
}