/*================================================================*/
/* MOBILE-FIRST RESPONSIVE CSS REDESIGN                           */
/* WCAG 2.1 AA Compliant | Accessible | Modern                   */
/*================================================================*/

/*================================================================*/
/* DESIGN TOKENS & CSS CUSTOM PROPERTIES                          */
/*================================================================*/
:root {
  /* Brand Colors - Enhanced contrast ratios */
  --color-brand-primary: #3730a3; /* Indigo 800 - Better contrast */
  --color-brand-primary-hover: #312e81; /* Indigo 900 */
  --color-brand-accent: #be185d; /* Pink 700 - Better contrast */
  --color-brand-accent-hover: #9d174d; /* Pink 800 */

  /* Light Theme Colors - WCAG AA Compliant */
  --color-bg-primary: #ffffff;
  --color-bg-secondary: #f8fafc; /* Slate 50 */
  --color-bg-tertiary: #f1f5f9; /* Slate 100 */
  --color-border: #cbd5e1; /* Slate 300 - Better visibility */
  --color-border-light: #e2e8f0; /* Slate 200 */
  --color-text-primary: #0f172a; /* Slate 900 - Maximum contrast */
  --color-text-secondary: #334155; /* Slate 700 - 4.5:1 contrast */
  --color-text-tertiary: #475569; /* Slate 600 */
  --color-text-link: #1e40af; /* Blue 800 - Better contrast */
  --color-text-link-hover: #1e3a8a; /* Blue 900 */

  /* Interactive States */
  --color-focus-ring: #3b82f6; /* Blue 500 */
  --color-favorite: #d97706; /* Amber 600 - Better contrast */
  --color-success: #059669; /* Emerald 600 */
  --color-warning: #d97706; /* Amber 600 */
  --color-error: #dc2626; /* Red 600 */

  /* Shadows */
  --shadow-color: 220 40% 15%;
  --shadow-sm: 0 1px 2px hsl(var(--shadow-color) / 0.1);
  --shadow-md: 0 4px 6px hsl(var(--shadow-color) / 0.1), 0 2px 4px hsl(var(--shadow-color) / 0.06);
  --shadow-lg: 0 10px 15px hsl(var(--shadow-color) / 0.1), 0 4px 6px hsl(var(--shadow-color) / 0.05);
  --shadow-xl: 0 20px 25px hsl(var(--shadow-color) / 0.1), 0 8px 10px hsl(var(--shadow-color) / 0.04);

  /* Typography Scale - Mobile First */
  --font-size-xs: 0.75rem; /* 12px */
  --font-size-sm: 0.875rem; /* 14px */
  --font-size-base: 1rem; /* 16px - WCAG minimum */
  --font-size-lg: 1.125rem; /* 18px */
  --font-size-xl: 1.25rem; /* 20px */
  --font-size-2xl: 1.5rem; /* 24px */
  --font-size-3xl: 1.875rem; /* 30px */
  --font-size-4xl: 2.25rem; /* 36px */
  --font-size-5xl: 3rem; /* 48px */

  /* Line Heights - Optimal readability */
  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.625;

  /* Spacing Scale - 8px base */
  --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 */

  /* Fonts */
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-heading: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-medium: 250ms ease-in-out;
  --transition-slow: 350ms ease-in-out;

  /* Border Radius */
  --radius-sm: 0.375rem; /* 6px */
  --radius-md: 0.5rem; /* 8px */
  --radius-lg: 0.75rem; /* 12px */
  --radius-xl: 1rem; /* 16px */
  --radius-2xl: 1.5rem; /* 24px */
  --radius-full: 9999px;

  /* Z-Index Scale */
  --z-dropdown: 10;
  --z-sticky: 20;
  --z-modal: 50;
  --z-tooltip: 60;
}

/* Dark Theme - Enhanced contrast */
.dark {
  --color-brand-primary: #6366f1; /* Indigo 500 */
  --color-brand-primary-hover: #818cf8; /* Indigo 400 */
  --color-brand-accent: #ec4899; /* Pink 500 */
  --color-brand-accent-hover: #f472b6; /* Pink 400 */

  --color-bg-primary: #0f172a; /* Slate 900 */
  --color-bg-secondary: #1e293b; /* Slate 800 */
  --color-bg-tertiary: #334155; /* Slate 700 */
  --color-border: #475569; /* Slate 600 */
  --color-border-light: #64748b; /* Slate 500 */
  --color-text-primary: #f8fafc; /* Slate 50 */
  --color-text-secondary: #cbd5e1; /* Slate 300 */
  --color-text-tertiary: #94a3b8; /* Slate 400 */
  --color-text-link: #60a5fa; /* Blue 400 */
  --color-text-link-hover: #93c5fd; /* Blue 300 */

  --color-focus-ring: #60a5fa; /* Blue 400 */
  --color-favorite: #fbbf24; /* Amber 400 */

  --shadow-color: 220 40% 2%;
}

/*================================================================*/
/* RESET & BASE STYLES - MOBILE FIRST                             */
/*================================================================*/
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 6rem; /* Mobile sticky header compensation */
  font-size: 100%; /* Respect user's font size preferences */
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-body);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  background-color: var(--color-bg-primary);
  color: var(--color-text-primary);
  transition: background-color var(--transition-medium), color var(--transition-medium);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Focus Management - WCAG Compliant */
:focus {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

:focus:not(:focus-visible) {
  outline: none;
}

:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

/* Links - Enhanced accessibility */
a {
  color: var(--color-text-link);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
  transition: color var(--transition-fast), text-decoration-color var(--transition-fast);
}

a:hover {
  color: var(--color-text-link-hover);
  text-decoration-thickness: 2px;
}

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

/* Typography Scale - Mobile First */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: var(--line-height-tight);
  margin: 0;
  color: var(--color-text-primary);
}

h1 {
  font-size: var(--font-size-3xl);
  font-weight: 800;
}

h2 {
  font-size: var(--font-size-2xl);
}

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

p {
  margin: 0;
  line-height: var(--line-height-relaxed);
}

/*================================================================*/
/* LAYOUT COMPONENTS - MOBILE FIRST                               */
/*================================================================*/

/* Container - Responsive padding */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-4);
}

/*================================================================*/
/* HEADER & NAVIGATION - MOBILE FIRST                             */
/*================================================================*/
header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background-color: var(--color-bg-primary);
  border-bottom: 1px solid var(--color-border-light);
  transition: background-color var(--transition-medium), backdrop-filter var(--transition-medium);
}

nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-3) var(--space-4);
  min-height: 3.5rem; /* 56px - adequate touch target */
}

/* Logo - Responsive sizing */
.webaide-logo {
  height: 2rem; /* 32px on mobile */
  width: auto;
  transition: transform var(--transition-medium);
}

.webaide-logo:hover {
  transform: scale(1.05);
}

/* Navigation Controls */
nav .flex {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

/*================================================================*/
/* BUTTONS - MOBILE FIRST & ACCESSIBLE                            */
/*================================================================*/
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: inherit;
  font-size: var(--font-size-sm);
  font-weight: 600;
  line-height: 1;
  text-decoration: none;
  border: 2px solid transparent;
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-fast);
  min-height: 2.75rem; /* 44px - WCAG touch target minimum */
  padding: var(--space-3) var(--space-4);
  position: relative;
  overflow: hidden;
}

.btn:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none !important;
}

.btn-primary {
  background-color: var(--color-brand-primary);
  color: white;
  border-color: var(--color-brand-primary);
}

.btn-primary:hover:not(:disabled) {
  background-color: var(--color-brand-primary-hover);
  border-color: var(--color-brand-primary-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

/* Theme Toggle Button */
#theme-toggle {
  width: 2.75rem; /* 44px - WCAG touch target */
  height: 2.75rem;
  padding: var(--space-2);
  border-radius: var(--radius-full);
  background-color: transparent;
  border: 1px solid var(--color-border);
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  justify-content: center;
}

#theme-toggle:hover {
  background-color: var(--color-bg-secondary);
  color: var(--color-brand-primary);
  border-color: var(--color-brand-primary);
  transform: scale(1.05);
}

#theme-toggle:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

/* Theme Toggle Icons */
#theme-toggle-moon {
  display: block;
}

#theme-toggle-sun {
  display: none;
}

.dark #theme-toggle-moon {
  display: none;
}

.dark #theme-toggle-sun {
  display: block;
}

/*================================================================*/
/* HERO SECTION - MOBILE FIRST                                    */
/*================================================================*/
.hero-section {
  padding: var(--space-8) var(--space-4);
  text-align: center;
  background: linear-gradient(
    135deg,
    rgba(79, 70, 229, 0.03) 0%,
    rgba(236, 72, 153, 0.03) 100%
  );
  position: relative;
  overflow: hidden;
}

.hero-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(
    circle at 20% 20%,
    rgba(79, 70, 229, 0.05) 0%,
    transparent 50%
  ),
  radial-gradient(
    circle at 80% 80%,
    rgba(236, 72, 153, 0.05) 0%,
    transparent 50%
  );
  pointer-events: none;
}

.dark .hero-section {
  background: linear-gradient(
    135deg,
    rgba(79, 70, 229, 0.08) 0%,
    rgba(236, 72, 153, 0.08) 100%
  );
}

.dark .hero-section::before {
  background: radial-gradient(
    circle at 20% 20%,
    rgba(79, 70, 229, 0.1) 0%,
    transparent 50%
  ),
  radial-gradient(
    circle at 80% 80%,
    rgba(236, 72, 153, 0.1) 0%,
    transparent 50%
  );
}

/* Hero Typography - Mobile First */
#main-heading {
  font-size: var(--font-size-3xl);
  font-weight: 800;
  line-height: var(--line-height-tight);
  margin-bottom: var(--space-4);
  color: var(--color-text-primary);
  position: relative;
  z-index: 1;
}

.hero-section p {
  font-size: var(--font-size-base);
  line-height: var(--line-height-relaxed);
  color: var(--color-text-secondary);
  margin-bottom: var(--space-6);
  max-width: 42rem;
  margin-left: auto;
  margin-right: auto;
  position: relative;
  z-index: 1;
}

/* Brand Text Styling */
.text-brand-primary {
  color: var(--color-brand-primary);
}

/*================================================================*/
/* SOCIAL SHARING - MOBILE FIRST                                  */
/*================================================================*/
#social-share-container {
  margin-top: var(--space-6);
  position: relative;
  z-index: 1;
}

#social-share-container p {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: var(--space-3);
}

#social-share-container .flex {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: var(--space-2);
}

.social-share-btn,
.copy-link-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 2.75rem; /* 44px - WCAG touch target */
  min-height: 2.75rem;
  padding: var(--space-2);
  background-color: var(--color-bg-secondary);
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  text-decoration: none;
  transition: all var(--transition-fast);
  cursor: pointer;
  font-size: var(--font-size-sm);
  font-weight: 500;
}

.copy-link-btn {
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-lg);
  gap: var(--space-1);
}

.social-share-btn:hover,
.copy-link-btn:hover {
  background-color: var(--color-brand-primary);
  color: white;
  border-color: var(--color-brand-primary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  text-decoration: none;
}

.social-share-btn:focus-visible,
.copy-link-btn:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

/*================================================================*/
/* SEARCH & FILTER SECTION - MOBILE FIRST                        */
/*================================================================*/
#search-and-filter-controls {
  position: sticky;
  top: 3.5rem; /* Below header */
  z-index: calc(var(--z-sticky) - 1);
  padding: var(--space-4);
  margin: 0 calc(-1 * var(--space-4));
  background-color: var(--color-bg-primary);
  border-bottom: 1px solid var(--color-border-light);
  transition: all var(--transition-medium);
}

#search-and-filter-controls.is-glassy {
  background-color: rgba(248, 250, 252, 0.85);
  backdrop-filter: blur(12px);
  border-bottom-color: var(--color-border);
  box-shadow: var(--shadow-sm);
}

.dark #search-and-filter-controls.is-glassy {
  background-color: rgba(15, 23, 42, 0.85);
}

#search-and-filter-controls.is-hidden {
  transform: translateY(-100%);
}

/* Search Container */
#search-container {
  position: relative;
  margin-bottom: var(--space-4);
}

#search-input {
  width: 100%;
  font-size: var(--font-size-lg);
  padding: var(--space-4) var(--space-4) var(--space-4) 3rem;
  border: 2px solid var(--color-border);
  border-radius: var(--radius-2xl);
  background-color: var(--color-bg-secondary);
  color: var(--color-text-primary);
  transition: all var(--transition-fast);
  min-height: 3.5rem; /* 56px - adequate touch target */
}

#search-input::placeholder {
  color: var(--color-text-tertiary);
  font-weight: 400;
}

#search-input:focus {
  border-color: var(--color-brand-primary);
  background-color: var(--color-bg-primary);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
  transform: translateY(-1px);
}

/* Search Icon */
#search-container .absolute {
  position: absolute;
  top: 50%;
  left: var(--space-4);
  transform: translateY(-50%);
  pointer-events: none;
  color: var(--color-text-tertiary);
}

/* Search Suggestions */
#suggestions-list {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background-color: var(--color-bg-primary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  margin-top: var(--space-1);
  box-shadow: var(--shadow-lg);
  z-index: var(--z-dropdown);
  max-height: 15rem;
  overflow-y: auto;
}

.suggestion-item {
  padding: var(--space-3) var(--space-4);
  cursor: pointer;
  transition: background-color var(--transition-fast);
  border-bottom: 1px solid var(--color-border-light);
  font-size: var(--font-size-base);
  color: var(--color-text-primary);
}

.suggestion-item:last-child {
  border-bottom: none;
}

.suggestion-item:hover,
.suggestion-item.active {
  background-color: var(--color-bg-secondary);
  color: var(--color-brand-primary);
}

.suggestion-item:focus {
  background-color: var(--color-bg-secondary);
  outline: none;
}

/*================================================================*/
/* FILTER BUTTONS - MOBILE FIRST                                  */
/*================================================================*/
#filter-container {
  display: flex;
  gap: var(--space-2);
  overflow-x: auto;
  padding-bottom: var(--space-2);
  margin-bottom: calc(-1 * var(--space-2));
  scrollbar-width: thin;
  scrollbar-color: var(--color-border) transparent;
}

#filter-container::-webkit-scrollbar {
  height: 3px;
}

#filter-container::-webkit-scrollbar-track {
  background: transparent;
}

#filter-container::-webkit-scrollbar-thumb {
  background-color: var(--color-border);
  border-radius: var(--radius-sm);
}

.filter-btn {
  flex-shrink: 0;
  padding: var(--space-2) var(--space-4);
  font-size: var(--font-size-sm);
  font-weight: 500;
  background-color: var(--color-bg-primary);
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
  min-height: 2.75rem; /* 44px - WCAG touch target */
}

.filter-btn:hover {
  background-color: var(--color-bg-secondary);
  color: var(--color-brand-primary);
  border-color: var(--color-brand-primary);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.filter-btn.active {
  background-color: var(--color-brand-primary);
  color: white;
  border-color: var(--color-brand-primary);
  box-shadow: var(--shadow-md);
}

.filter-btn:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

/*================================================================*/
/* RESOURCE CARDS - MOBILE FIRST                                  */
/*================================================================*/
#resources {
  margin-top: var(--space-8);
}

/* Section Styling */
#resources > section {
  margin-bottom: var(--space-12);
}

#resources > section:nth-of-type(even) {
  background-color: var(--color-bg-secondary);
  padding: var(--space-8) var(--space-4);
  margin: var(--space-8) calc(-1 * var(--space-4)) var(--space-12);
  border-radius: var(--radius-xl);
}

/* Section Headers */
#resources > section > h2 {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  margin-bottom: var(--space-8);
  padding-left: var(--space-4);
  border-left: 4px solid var(--color-brand-primary);
  display: flex;
  align-items: center;
  gap: var(--space-3);
  color: var(--color-text-primary);
}

#resources > section > h2 svg {
  width: 1.5rem;
  height: 1.5rem;
  color: var(--color-brand-accent);
  flex-shrink: 0;
}

/* Grid Layout - Mobile First */
#resources .grid {
  display: grid;
  grid-template-columns: 1fr; /* Single column on mobile */
  gap: var(--space-4);
}

/* Resource Cards */
.resource-card {
  position: relative;
  display: flex;
  flex-direction: column;
  min-height: 12rem; /* 192px */
  padding: var(--space-6);
  background-color: var(--color-bg-primary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-medium);
  opacity: 0;
  transform: translateY(20px);
}

.resource-card.is-visible {
  opacity: 1;
  transform: translateY(0);
  transition-delay: var(--delay, 0s);
}

.resource-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: var(--color-brand-primary);
}

/* Card Content */
.resource-card .flex-grow {
  flex: 1;
  padding-right: var(--space-12); /* Space for actions */
}

.resource-card h3 {
  margin-bottom: var(--space-3);
}

.resource-card h3 a {
  font-size: var(--font-size-lg);
  font-weight: 600;
  line-height: var(--line-height-tight);
  color: var(--color-text-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.resource-card h3 a:hover {
  color: var(--color-brand-primary);
  text-decoration: underline;
}

.resource-card h3 a:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.resource-card p {
  font-size: var(--font-size-sm);
  line-height: var(--line-height-relaxed);
  color: var(--color-text-secondary);
  margin-top: var(--space-2);
}

/* Card Actions */
.card-actions {
  position: absolute;
  top: var(--space-3);
  right: var(--space-3);
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.card-menu-btn,
.favorite-btn {
  width: 2.5rem; /* 40px */
  height: 2.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: transparent;
  border: 1px solid transparent;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--transition-fast);
  color: var(--color-text-tertiary);
}

.card-menu-btn:hover,
.favorite-btn:hover {
  background-color: var(--color-bg-secondary);
  color: var(--color-text-primary);
  border-color: var(--color-border);
  transform: scale(1.1);
}

.card-menu-btn:focus-visible,
.favorite-btn:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

/* Favorite Button States */
.favorite-btn {
  color: var(--color-text-tertiary);
}

.favorite-btn:hover {
  color: var(--color-favorite);
}

.favorite-btn.active {
  color: var(--color-favorite);
  transform: scale(1.1);
}

.favorite-btn .star-outline {
  display: block;
}

.favorite-btn .star-fill {
  display: none;
}

.favorite-btn.active .star-outline {
  display: none;
}

.favorite-btn.active .star-fill {
  display: block;
}

/* Card Menu */
.card-menu {
  position: absolute;
  top: 100%;
  right: 0;
  min-width: 10rem;
  background-color: var(--color-bg-primary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  z-index: var(--z-dropdown);
  padding: var(--space-1);
  margin-top: var(--space-1);
}

.card-menu-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  width: 100%;
  padding: var(--space-2) var(--space-3);
  font-size: var(--font-size-sm);
  color: var(--color-text-primary);
  background-color: transparent;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background-color var(--transition-fast);
  text-align: left;
}

.card-menu-item:hover {
  background-color: var(--color-bg-secondary);
  color: var(--color-brand-primary);
}

.card-menu-item:focus {
  background-color: var(--color-bg-secondary);
  outline: none;
}

.card-menu-item svg {
  width: 1rem;
  height: 1rem;
  flex-shrink: 0;
}

/*================================================================*/
/* MODAL - MOBILE FIRST & ACCESSIBLE                              */
/*================================================================*/
#feedback-modal-overlay {
  position: fixed;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.6);
  z-index: var(--z-modal);
  padding: var(--space-4);
  transition: opacity var(--transition-medium);
}

#feedback-modal {
  position: relative;
  width: 100%;
  max-width: 32rem; /* 512px */
  max-height: 90vh;
  margin: auto;
  background-color: var(--color-bg-primary);
  border-radius: var(--radius-2xl);
  box-shadow: var(--shadow-xl);
  padding: var(--space-6);
  overflow-y: auto;
  transform: scale(0.95);
  opacity: 0;
  transition: all var(--transition-medium);
}

#feedback-modal-overlay:not(.hidden) #feedback-modal {
  transform: scale(1);
  opacity: 1;
}

#feedback-modal-title {
  font-size: var(--font-size-xl);
  font-weight: 700;
  margin-bottom: var(--space-6);
  color: var(--color-text-primary);
}

#close-feedback-modal-btn {
  position: absolute;
  top: var(--space-4);
  right: var(--space-4);
  width: 2.5rem;
  height: 2.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: transparent;
  border: none;
  border-radius: var(--radius-full);
  color: var(--color-text-tertiary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

#close-feedback-modal-btn:hover {
  background-color: var(--color-bg-secondary);
  color: var(--color-text-primary);
}

#close-feedback-modal-btn:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

/* Form Styles */
.form-label {
  display: block;
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-text-primary);
  margin-bottom: var(--space-1);
}

.form-input {
  width: 100%;
  padding: var(--space-3);
  font-size: var(--font-size-base);
  background-color: var(--color-bg-primary);
  color: var(--color-text-primary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  min-height: 2.75rem; /* 44px - WCAG touch target */
}

.form-input:focus {
  border-color: var(--color-brand-primary);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
  outline: none;
}

.form-input::placeholder {
  color: var(--color-text-tertiary);
}

.form-radio {
  width: 1rem;
  height: 1rem;
  color: var(--color-brand-primary);
  border-color: var(--color-border);
  transition: all var(--transition-fast);
}

.form-radio:focus {
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

/* Form Grid */
.grid {
  display: grid;
  gap: var(--space-4);
}

.grid.grid-cols-1 {
  grid-template-columns: 1fr;
}

.space-y-4 > * + * {
  margin-top: var(--space-4);
}

/*================================================================*/
/* BACK TO TOP BUTTON - MOBILE FIRST                              */
/*================================================================*/
#back-to-top {
  position: fixed;
  bottom: var(--space-4);
  right: var(--space-4);
  width: 3rem; /* 48px */
  height: 3rem;
  background-color: var(--color-brand-primary);
  color: white;
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  box-shadow: var(--shadow-lg);
  z-index: calc(var(--z-modal) - 10);
  opacity: 0;
  transform: translateY(20px);
  transition: all var(--transition-medium);
  display: none;
}

#back-to-top.visible {
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 1;
  transform: translateY(0);
}

#back-to-top:hover {
  background-color: var(--color-brand-primary-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
}

#back-to-top:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

/*================================================================*/
/* FOOTER - MOBILE FIRST                                          */
/*================================================================*/
.site-footer {
  margin-top: var(--space-16);
  padding: var(--space-8) var(--space-4);
  background-color: var(--color-bg-secondary);
  border-top: 1px solid var(--color-border);
}

.site-footer .container {
  max-width: 75rem; /* 1200px */
}

.site-footer .grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-6);
}

.footer-heading {
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: var(--space-3);
}

.footer-about p,
.footer-connect p {
  font-size: var(--font-size-sm);
  line-height: var(--line-height-relaxed);
  color: var(--color-text-secondary);
  margin-bottom: var(--space-3);
}

.footer-links ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-links li {
  margin-bottom: var(--space-2);
}

.footer-links a {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: var(--color-brand-primary);
  text-decoration: underline;
}

.footer-links a:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* GitHub Link */
.github-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-text-primary);
  background-color: var(--color-bg-primary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  text-decoration: none;
  transition: all var(--transition-fast);
}

.github-link:hover {
  color: var(--color-brand-primary);
  border-color: var(--color-brand-primary);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
  text-decoration: none;
}

.github-link:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

.github-link svg {
  width: 1rem;
  height: 1rem;
  flex-shrink: 0;
}

.footer-copyright {
  margin-top: var(--space-6);
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-border);
  text-align: center;
  font-size: var(--font-size-xs);
  color: var(--color-text-tertiary);
}

/*================================================================*/
/* UTILITY CLASSES                                                */
/*================================================================*/
.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;
}

.hidden {
  display: none !important;
}

/* Skip Links - WCAG Compliant */
.skip-link {
  position: absolute;
  left: -9999px;
  top: auto;
  width: 1px;
  height: 1px;
  overflow: hidden;
  z-index: -9999;
}

.skip-link:focus {
  position: fixed;
  top: var(--space-3);
  left: var(--space-3);
  width: auto;
  height: auto;
  padding: var(--space-2) var(--space-4);
  background-color: var(--color-brand-primary);
  color: white;
  font-weight: 600;
  border-radius: var(--radius-md);
  z-index: 9999;
  text-decoration: none;
}

/* No Results Message */
#no-results-message {
  text-align: center;
  padding: var(--space-12) var(--space-4);
}

#no-results-message h3 {
  font-size: var(--font-size-xl);
  font-weight: 700;
  color: var(--color-text-primary);
  margin-bottom: var(--space-2);
}

#no-results-message p {
  font-size: var(--font-size-base);
  color: var(--color-text-secondary);
}

/* Skeleton Loader */
@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

.skeleton-card {
  background-color: var(--color-bg-secondary);
  border-radius: var(--radius-xl);
  height: 12rem; /* 192px */
  animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/*================================================================*/
/* RESPONSIVE BREAKPOINTS - MIN-WIDTH APPROACH                    */
/*================================================================*/

/* Small tablets and large phones (480px+) */
@media (min-width: 30rem) {
  .container {
    padding: 0 var(--space-6);
  }

  nav {
    padding: var(--space-4) var(--space-6);
  }

  .webaide-logo {
    height: 2.25rem; /* 36px */
  }

  .btn {
    font-size: var(--font-size-base);
    padding: var(--space-3) var(--space-5);
  }

  #theme-toggle {
    width: 3rem; /* 48px */
    height: 3rem;
  }

  .hero-section {
    padding: var(--space-10) var(--space-6);
  }

  #main-heading {
    font-size: var(--font-size-4xl);
  }

  .hero-section p {
    font-size: var(--font-size-lg);
  }

  #search-input {
    font-size: var(--font-size-xl);
    padding: var(--space-5) var(--space-5) var(--space-5) 3.5rem;
  }

  #search-container .absolute {
    left: var(--space-5);
  }

  .filter-btn {
    font-size: var(--font-size-base);
    padding: var(--space-3) var(--space-5);
  }

  #resources .grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-5);
  }

  .resource-card {
    padding: var(--space-7);
  }

  .resource-card h3 a {
    font-size: var(--font-size-xl);
  }

  .resource-card p {
    font-size: var(--font-size-base);
  }

  .card-actions {
    top: var(--space-4);
    right: var(--space-4);
    gap: var(--space-2);
  }

  .card-menu-btn,
  .favorite-btn {
    width: 2.75rem; /* 44px */
    height: 2.75rem;
  }

  #resources > section > h2 {
    font-size: var(--font-size-3xl);
    gap: var(--space-4);
  }

  #resources > section > h2 svg {
    width: 2rem;
    height: 2rem;
  }

  #back-to-top {
    width: 3.5rem; /* 56px */
    height: 3.5rem;
  }
}

/* Tablets (768px+) */
@media (min-width: 48rem) {
  .container {
    padding: 0 var(--space-8);
  }

  nav {
    padding: var(--space-5) var(--space-8);
  }

  nav .flex {
    gap: var(--space-4);
  }

  .webaide-logo {
    height: 2.5rem; /* 40px */
  }

  .hero-section {
    padding: var(--space-12) var(--space-8);
  }

  #main-heading {
    font-size: var(--font-size-5xl);
    margin-bottom: var(--space-5);
  }

  #search-and-filter-controls {
    padding: var(--space-5) var(--space-8);
    margin: 0 calc(-1 * var(--space-8));
  }

  #search-input {
    padding: var(--space-6) var(--space-6) var(--space-6) 4rem;
    min-height: 4rem; /* 64px */
  }

  #search-container .absolute {
    left: var(--space-6);
  }

  #search-container .absolute svg {
    width: 1.5rem;
    height: 1.5rem;
  }

  .filter-btn {
    padding: var(--space-3) var(--space-6);
  }

  #resources .grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-6);
  }

  .resource-card {
    min-height: 14rem; /* 224px */
    padding: var(--space-8);
  }

  .card-actions {
    top: var(--space-5);
    right: var(--space-5);
  }

  #resources > section:nth-of-type(even) {
    padding: var(--space-10) var(--space-8);
    margin: var(--space-10) calc(-1 * var(--space-8)) var(--space-12);
  }

  #feedback-modal {
    max-width: 42rem; /* 672px */
    padding: var(--space-8);
  }

  .site-footer .grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* Small desktops (1024px+) */
@media (min-width: 64rem) {
  html {
    scroll-padding-top: 8rem;
  }

  .container {
    max-width: 80rem; /* 1280px */
  }

  .webaide-logo {
    height: 3rem; /* 48px */
  }

  .hero-section {
    padding: var(--space-16) var(--space-8);
  }

  #main-heading {
    font-size: clamp(var(--font-size-4xl), 5vw, var(--font-size-5xl));
  }

  #search-input {
    font-size: var(--font-size-2xl);
    padding: var(--space-6) var(--space-8) var(--space-6) 4.5rem;
  }

  #search-container .absolute {
    left: var(--space-8);
  }

  #search-container .absolute svg {
    width: 1.75rem;
    height: 1.75rem;
  }

  #resources .grid {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-8);
  }

  .resource-card {
    min-height: 16rem; /* 256px */
  }

  .resource-card h3 a {
    font-size: var(--font-size-2xl);
  }

  .resource-card p {
    font-size: var(--font-size-lg);
  }

  .card-menu-btn,
  .favorite-btn {
    width: 3rem; /* 48px */
    height: 3rem;
  }

  .card-menu {
    min-width: 12rem; /* 192px */
  }

  #resources > section > h2 {
    font-size: var(--font-size-4xl);
    gap: var(--space-5);
  }

  #resources > section > h2 svg {
    width: 2.5rem;
    height: 2.5rem;
  }
}

/* Large desktops (1280px+) */
@media (min-width: 80rem) {
  .container {
    max-width: 90rem; /* 1440px */
  }

  #resources .grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .resource-card {
    min-height: 18rem; /* 288px */
  }

  #resources > section > h2 {
    font-size: clamp(var(--font-size-3xl), 3vw, var(--font-size-4xl));
  }
}

/* Extra large screens (1536px+) */
@media (min-width: 96rem) {
  .container {
    max-width: 100rem; /* 1600px */
  }

  .hero-section {
    padding: var(--space-20) var(--space-8);
  }

  #main-heading {
    font-size: clamp(var(--font-size-5xl), 4vw, 4rem);
  }

  #resources .grid {
    grid-template-columns: repeat(5, 1fr);
  }
}

/*================================================================*/
/* HIGH CONTRAST MODE SUPPORT                                     */
/*================================================================*/
@media (prefers-contrast: high) {
  :root {
    --color-border: #64748b;
    --color-text-secondary: #1e293b;
  }

  .dark {
    --color-border: #94a3b8;
    --color-text-secondary: #e2e8f0;
  }

  .resource-card {
    border-width: 2px;
  }

  .btn {
    border-width: 2px;
  }
}

/*================================================================*/
/* REDUCED MOTION SUPPORT                                         */
/*================================================================*/
@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;
  }

  .resource-card {
    transform: none !important;
  }

  .resource-card:hover {
    transform: none !important;
  }

  #back-to-top {
    transform: none !important;
  }

  #back-to-top.visible {
    transform: none !important;
  }
}

/*================================================================*/
/* PRINT STYLES                                                   */
/*================================================================*/
@media print {
  /* Hide interactive elements */
  .skip-link,
  #theme-toggle,
  #back-to-top,
  .card-actions,
  #search-and-filter-controls,
  .site-footer {
    display: none !important;
  }

  /* Optimize for print */
  body {
    background: white !important;
    color: black !important;
    font-size: 12pt;
    line-height: 1.4;
  }

  .resource-card {
    break-inside: avoid;
    box-shadow: none;
    border: 1px solid #000;
    margin-bottom: 1rem;
  }

  .resource-card h3 a {
    color: black !important;
  }

  .resource-card h3 a::after {
    content: " (" attr(href) ")";
    font-size: 10pt;
    color: #666;
  }

  #resources > section > h2 {
    border-left-color: #000;
    color: black !important;
  }

  /* Ensure good contrast for print */
  * {
    background: transparent !important;
    color: black !important;
    box-shadow: none !important;
  }
}

/*================================================================*/
/* ACCESSIBILITY ENHANCEMENTS                                     */
/*================================================================*/

/* Enhanced focus indicators for better visibility */
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible,
[role="button"]:focus-visible,
[role="menuitem"]:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* Ensure adequate spacing for touch targets */
button,
input,
select,
textarea,
[role="button"],
[role="menuitem"] {
  min-height: 2.75rem; /* 44px - WCAG AAA touch target */
}

/* High contrast borders for better definition */
.resource-card,
.form-input,
.filter-btn,
#search-input {
  border-width: 1px;
  border-style: solid;
}

/* Ensure text remains readable during transitions */
* {
  transition-property: transform, box-shadow, background-color, border-color, opacity;
}

/* Color should not transition to maintain readability */
*:not(a):not(.btn):not(.filter-btn):not(.social-share-btn):not(.copy-link-btn) {
  transition-property: transform, box-shadow, background-color, border-color, opacity;
}

/*================================================================*/
/* RESPONSIVE TYPOGRAPHY IMPROVEMENTS                             */
/*================================================================*/

/* Fluid typography for better scaling */
@media (min-width: 30rem) {
  #main-heading {
    font-size: clamp(var(--font-size-3xl), 6vw, var(--font-size-5xl));
  }

  #resources > section > h2 {
    font-size: clamp(var(--font-size-2xl), 4vw, var(--font-size-4xl));
  }
}

/* Ensure minimum font sizes are maintained */
@media (max-width: 29.99rem) {
  .resource-card h3 a {
    font-size: var(--font-size-base); /* Never smaller than 16px */
  }

  .resource-card p {
    font-size: var(--font-size-sm);
    line-height: var(--line-height-relaxed);
  }
}

/*================================================================*/
/* ENHANCED INTERACTIVE STATES                                    */
/*================================================================*/

/* Improved hover states with better feedback */
.resource-card:hover {
  border-color: var(--color-brand-primary);
}

.resource-card:focus-within {
  border-color: var(--color-brand-primary);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

/* Better visual feedback for interactive elements */
.filter-btn:active,
.btn:active {
  transform: translateY(0);
}

/* Ensure sufficient color contrast for all states */
.filter-btn.active {
  background-color: var(--color-brand-primary);
  color: white;
  border-color: var(--color-brand-primary);
}

.filter-btn.active:hover {
  background-color: var(--color-brand-primary-hover);
  border-color: var(--color-brand-primary-hover);
}

/*================================================================*/
/* IMPROVED SPACING & LAYOUT                                      */
/*================================================================*/

/* Better content spacing on mobile */
@media (max-width: 29.99rem) {
  .hero-section {
    padding: var(--space-6) var(--space-3);
  }

  #search-and-filter-controls {
    padding: var(--space-3);
    margin: 0 calc(-1 * var(--space-3));
  }

  #resources > section:nth-of-type(even) {
    padding: var(--space-6) var(--space-3);
    margin: var(--space-6) calc(-1 * var(--space-3)) var(--space-8);
  }

  .resource-card {
    padding: var(--space-5);
    min-height: 10rem; /* 160px - smaller on mobile */
  }

  .card-actions {
    top: var(--space-2);
    right: var(--space-2);
  }

  .card-menu-btn,
  .favorite-btn {
    width: 2.25rem; /* 36px */
    height: 2.25rem;
  }
}

/*================================================================*/
/* ENHANCED GRID SYSTEM                                           */
/*================================================================*/

/* Responsive grid with better breakpoint management */
@media (min-width: 48rem) and (max-width: 63.99rem) {
  #resources .grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-6);
  }
}

@media (min-width: 64rem) and (max-width: 79.99rem) {
  #resources .grid {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-8);
  }
}

@media (min-width: 80rem) {
  #resources .grid {
    grid-template-columns: repeat(auto-fit, minmax(18rem, 1fr));
    gap: var(--space-8);
  }
}

/*================================================================*/
/* ACCESSIBILITY ANNOUNCEMENTS                                    */
/*================================================================*/
#announcer,
#search-results-announcer {
  position: absolute;
  left: -10000px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

/*================================================================*/
/* ENHANCED FORM ACCESSIBILITY                                    */
/*================================================================*/
fieldset {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  margin: 0;
}

legend {
  padding: 0 var(--space-2);
  font-weight: 600;
  color: var(--color-text-primary);
}

/* Radio button styling for better accessibility */
.form-radio {
  width: 1.125rem; /* 18px */
  height: 1.125rem;
  margin-right: var(--space-2);
}

/* Ensure form labels are properly associated */
label {
  cursor: pointer;
}

/* Required field indicators */
.text-red-500 {
  color: var(--color-error);
}

/*================================================================*/
/* PERFORMANCE OPTIMIZATIONS                                      */
/*================================================================*/

/* Optimize animations for better performance */
.resource-card,
.btn,
.filter-btn {
  will-change: transform;
}

.resource-card.is-visible {
  will-change: auto;
}

/* Optimize backdrop-filter usage */
#search-and-filter-controls.is-glassy {
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

/*================================================================*/
/* BROWSER COMPATIBILITY                                          */
/*================================================================*/

/* Safari-specific fixes */
@supports (-webkit-appearance: none) {
  .form-input,
  #search-input {
    appearance: none;
    -webkit-appearance: none;
  }
}

/* Firefox-specific fixes */
@-moz-document url-prefix() {
  .filter-btn {
    padding: calc(var(--space-3) + 1px) var(--space-4);
  }
}

/* Edge/IE compatibility */
@supports not (backdrop-filter: blur(8px)) {
  #search-and-filter-controls.is-glassy {
  background-color: var(--color-bg-p  rimary);
  }
}
/*================================================================*/