/* ==========================================================================
   POPBRIZ GLOBAL - DESIGN HUB PROFESSIONAL CSS
   Advanced Responsive Design System
   Version: 3.0 | Optimized for designs.php
   ========================================================================== */

/* ==========================================================================
   CSS CUSTOM PROPERTIES (Design Tokens)
   ========================================================================== */
:root {
  /* Color System */
  --color-primary: #4F46E5;
  --color-primary-dark: #3730A3;
  --color-primary-light: #818CF8;
  --color-secondary: #F59E0B;
  --color-secondary-dark: #D97706;
  --color-accent: #10B981;
  --color-danger: #EF4444;
  --color-success: #10B981;
  
  /* Neutral Colors */
  --color-white: #FFFFFF;
  --color-gray-50: #F9FAFB;
  --color-gray-100: #F3F4F6;
  --color-gray-200: #E5E7EB;
  --color-gray-300: #D1D5DB;
  --color-gray-400: #9CA3AF;
  --color-gray-500: #6B7280;
  --color-gray-600: #4B5563;
  --color-gray-700: #374151;
  --color-gray-800: #1F2937;
  --color-gray-900: #111827;
  --color-black: #000000;
  
  /* Gradients */
  --gradient-primary: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
  --gradient-secondary: linear-gradient(135deg, var(--color-secondary) 0%, var(--color-secondary-dark) 100%);
  --gradient-accent: linear-gradient(135deg, #8B5CF6 0%, #EC4899 100%);
  --gradient-premium: linear-gradient(135deg, #FCD34D 0%, #F59E0B 50%, #DC2626 100%);
  --gradient-ai: linear-gradient(135deg, #06B6D4 0%, #3B82F6 100%);
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  
  /* Typography */
  --font-family-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-family-mono: 'SF Mono', Monaco, 'Cascadia Mono', 'Segoe UI Mono', 'Roboto Mono', monospace;
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
  
  /* Z-index Layers */
  --z-below: -1;
  --z-base: 1;
  --z-above: 10;
  --z-dropdown: 1000;
  --z-sticky: 1100;
  --z-fixed: 1200;
  --z-modal: 1300;
  --z-popover: 1400;
  --z-toast: 1500;
  --z-tooltip: 1600;
}

/* ==========================================================================
   CSS RESET & BASE STYLES (Modern Approach)
   ========================================================================== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family-sans);
  line-height: 1.6;
  color: var(--color-gray-800);
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
}

body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: 
    radial-gradient(circle at 20% 80%, rgba(120, 119, 198, 0.3) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(255, 119, 198, 0.3) 0%, transparent 50%);
  z-index: -1;
  pointer-events: none;
}

/* ==========================================================================
   TYPOGRAPHY SYSTEM
   ========================================================================== */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.025em;
  color: var(--color-gray-900);
}

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

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

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

/* ==========================================================================
   HEADER & NAVIGATION - PROFESSIONAL LAYOUT
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(10px) saturate(180%);
  -webkit-backdrop-filter: blur(10px) saturate(180%);
  border-bottom: 1px solid rgba(255, 255, 255, 0.2);
  box-shadow: var(--shadow-lg);
  padding: var(--spacing-sm) 0;
  transition: all var(--transition-base);
}

.site-header.scrolled {
  padding: var(--spacing-xs) 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
}

.navbar__container {
  max-width: 1440px;
  margin: 0 auto;
  padding: 0 var(--spacing-xl);
  display: grid;
  grid-template-columns: auto auto 1fr auto auto;
  align-items: center;
  gap: var(--spacing-lg);
  position: relative;
}

/* Logo */
#navbar__logo {
  display: flex;
  align-items: center;
  position: relative;
  z-index: var(--z-above);
}

#navbar__logo img {
  height: 48px;
  width: auto;
  transition: all var(--transition-base);
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
}

#navbar__logo:hover img {
  transform: scale(1.05) rotate(-2deg);
  filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.15));
}

/* Home Button */
.home-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-lg);
  background: var(--gradient-primary);
  color: var(--color-white);
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: 0.9375rem;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-md);
  border: 2px solid transparent;
}

.home-btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.6s ease;
}

.home-btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
  border-color: rgba(255, 255, 255, 0.3);
}

.home-btn:hover::before {
  left: 100%;
}

.home-icon {
  font-size: 1.25rem;
  filter: drop-shadow(0 2px 3px rgba(0, 0, 0, 0.2));
}

.home-text {
  font-weight: 600;
}

/* Search Container */
.search-container {
  position: relative;
  max-width: 500px;
  margin: 0 auto;
}

#searchInput {
  width: 100%;
  padding: var(--spacing-md) var(--spacing-xl);
  padding-right: 4.5rem;
  background: var(--color-white);
  border: 2px solid var(--color-gray-200);
  border-radius: var(--radius-full);
  font-size: 0.9375rem;
  color: var(--color-gray-800);
  transition: all var(--transition-base);
  box-shadow: var(--shadow-sm);
}

#searchInput:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1), var(--shadow-md);
  background: var(--color-white);
}

#searchInput::placeholder {
  color: var(--color-gray-500);
}

#searchBtn {
  position: absolute;
  right: 4px;
  top: 50%;
  transform: translateY(-50%);
  padding: 0.625rem 1.5rem;
  background: var(--gradient-primary);
  color: var(--color-white);
  border: none;
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: 0.875rem;
  cursor: pointer;
  transition: all var(--transition-base);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  box-shadow: var(--shadow-md);
}

#searchBtn:hover {
  transform: translateY(-50%) scale(1.05);
  box-shadow: var(--shadow-lg);
}

.search-icon {
  font-size: 1rem;
}

.search-text {
  display: inline;
}

/* Desktop Navigation */
.desktop-nav {
  display: none;
}

.nav-links {
  display: flex;
  gap: var(--spacing-md);
  list-style: none;
}

.nav-link {
  padding: var(--spacing-sm) var(--spacing-lg);
  color: var(--color-gray-700);
  font-weight: 600;
  font-size: 0.9375rem;
  border-radius: var(--radius-full);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.nav-link::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity var(--transition-base);
  z-index: -1;
  border-radius: var(--radius-full);
}

.nav-link:hover {
  color: var(--color-primary);
  transform: translateY(-1px);
}

.nav-link.active {
  color: var(--color-white);
  background: var(--gradient-primary);
  box-shadow: var(--shadow-md);
}

.nav-link.active::before {
  opacity: 1;
}

.premium-link {
  background: var(--gradient-premium);
  color: var(--color-gray-900) !important;
  font-weight: 700;
  box-shadow: var(--shadow-md);
  border: 2px solid transparent;
  position: relative;
  overflow: hidden;
}

.premium-link::after {
  content: '';
  position: absolute;
  top: -2px;
  left: -2px;
  right: -2px;
  bottom: -2px;
  background: var(--gradient-premium);
  border-radius: var(--radius-full);
  z-index: -1;
  opacity: 0;
  transition: opacity var(--transition-base);
  animation: shimmer 2s infinite;
}

.premium-link:hover::after {
  opacity: 1;
}

.premium-link:hover {
  transform: translateY(-2px) scale(1.05);
  box-shadow: var(--shadow-xl);
}

.crown {
  font-size: 1.1em;
  filter: drop-shadow(0 2px 3px rgba(0, 0, 0, 0.3));
  animation: bounce 2s infinite;
}

@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-3px); }
}

/* AI Button Styles (Preserved & Enhanced) */
.ai-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-lg);
  background: var(--gradient-ai);
  color: var(--color-white);
  border-radius: var(--radius-full);
  font-weight: 700;
  font-size: 0.9375rem;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-md);
  border: 2px solid transparent;
}

.ai-btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(45deg, transparent 30%, rgba(255, 255, 255, 0.3) 50%, transparent 70%);
  background-size: 200% 100%;
  animation: aiShimmer 3s infinite;
  z-index: 1;
}

.ai-btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
  border-color: rgba(255, 255, 255, 0.3);
}

.ai-btn:hover::before {
  animation: aiShimmer 1s infinite;
}

.ai-icon {
  font-size: 1.1rem;
  font-weight: 900;
  background: var(--color-white);
  color: var(--color-primary);
  width: 26px;
  height: 26px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  z-index: 2;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.ai-label {
  position: relative;
  z-index: 2;
  font-weight: 600;
}

@keyframes aiShimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

@keyframes shimmer {
  0% { background-position: -1000px 0; }
  100% { background-position: 1000px 0; }
}

/* Mobile Navigation Toggle */
.mobile-nav-toggle {
  display: none;
  background: none;
  border: none;
  width: 40px;
  height: 40px;
  cursor: pointer;
  position: relative;
  z-index: var(--z-fixed);
}

.mobile-nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-gray-700);
  margin: 5px auto;
  transition: all var(--transition-fast);
  transform-origin: center;
}

/* Mobile Navigation */
.mobile-nav {
  position: fixed;
  top: 0;
  right: 0;
  width: 100%;
  height: 100vh;
  background: rgba(0, 0, 0, 0.8);
  backdrop-filter: blur(10px);
  z-index: var(--z-modal);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
}

.mobile-nav.active {
  opacity: 1;
  visibility: visible;
}

.mobile-nav-content {
  position: absolute;
  top: 0;
  right: 0;
  width: 90%;
  max-width: 380px;
  height: 100%;
  background: var(--color-white);
  padding: var(--spacing-3xl) var(--spacing-xl);
  transform: translateX(100%);
  transition: transform var(--transition-base) var(--transition-base);
  overflow-y: auto;
  box-shadow: var(--shadow-2xl);
}

.mobile-nav.active .mobile-nav-content {
  transform: translateX(0);
}

.mobile-nav-links {
  list-style: none;
  margin-top: var(--spacing-2xl);
}

.mobile-nav-link {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
  padding: var(--spacing-lg);
  color: var(--color-gray-700);
  font-weight: 600;
  font-size: 1.125rem;
  border-radius: var(--radius-lg);
  transition: all var(--transition-base);
  margin-bottom: var(--spacing-sm);
}

.mobile-nav-link:hover {
  background: var(--color-gray-50);
  color: var(--color-primary);
  transform: translateX(10px);
}

.mobile-nav-link.active {
  background: var(--gradient-primary);
  color: var(--color-white);
  box-shadow: var(--shadow-md);
}

.mobile-nav-link.premium-link {
  background: var(--gradient-premium);
  color: var(--color-gray-900);
  font-weight: 700;
}

.nav-icon {
  font-size: 1.5rem;
  width: 32px;
  text-align: center;
}

/* ==========================================================================
   MAIN CONTENT AREA
   ========================================================================== */
main {
  min-height: calc(100vh - 80px);
  padding: var(--spacing-2xl) var(--spacing-xl);
  max-width: 1440px;
  margin: 0 auto;
  position: relative;
}

/* Loading State */
.content-loader {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
  z-index: var(--z-modal);
}

.loader-spinner {
  width: 80px;
  height: 80px;
  border: 4px solid rgba(255, 255, 255, 0.1);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-bottom: var(--spacing-lg);
  position: relative;
}

.loader-spinner::after {
  content: '';
  position: absolute;
  top: -4px;
  left: -4px;
  right: -4px;
  bottom: -4px;
  border: 4px solid transparent;
  border-top-color: var(--color-secondary);
  border-radius: 50%;
  animation: spin 1.5s linear infinite reverse;
}

.content-loader p {
  color: var(--color-white);
  font-size: 1.25rem;
  font-weight: 600;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Main Content Wrapper */
.main-content-wrapper {
  animation: contentFadeIn 0.8s cubic-bezier(0.4, 0, 0.2, 1) forwards;
  opacity: 0;
}

@keyframes contentFadeIn {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ==========================================================================
   RESPONSIVE DESIGN SYSTEM
   ========================================================================== */

/* Desktop (≥1024px) */
@media screen and (min-width: 1024px) {
  .desktop-nav {
    display: block;
  }
  
  .mobile-nav-toggle {
    display: none;
  }
  
  .navbar__container {
    grid-template-columns: auto auto 1fr auto auto;
    gap: var(--spacing-xl);
  }
  
  .search-container {
    max-width: 500px;
  }
}

/* Tablet (768px - 1023px) */
@media screen and (max-width: 1023px) and (min-width: 768px) {
  .navbar__container {
    grid-template-columns: auto 1fr auto auto;
    gap: var(--spacing-lg);
    padding: 0 var(--spacing-lg);
  }
  
  .desktop-nav {
    display: none;
  }
  
  .mobile-nav-toggle {
    display: block;
    order: 5;
  }
  
  .search-container {
    order: 3;
    grid-column: 1 / -1;
    margin-top: var(--spacing-md);
  }
  
  .ai-btn {
    order: 4;
  }
  
  .home-text {
    display: none;
  }
  
  .home-btn {
    padding: var(--spacing-sm);
    width: 44px;
    height: 44px;
    justify-content: center;
  }
  
  .home-icon {
    margin: 0;
    font-size: 1.5rem;
  }
}

/* Large Mobile (480px - 767px) */
@media screen and (max-width: 767px) and (min-width: 480px) {
  .navbar__container {
    grid-template-columns: auto 1fr auto auto;
    padding: 0 var(--spacing-md);
    gap: var(--spacing-md);
  }
  
  #navbar__logo img {
    height: 40px;
  }
  
  .home-btn,
  .ai-btn {
    padding: var(--spacing-sm);
    width: 44px;
    height: 44px;
    justify-content: center;
  }
  
  .home-text,
  .ai-label,
  .search-text {
    display: none;
  }
  
  .home-icon,
  .ai-icon {
    margin: 0;
    font-size: 1.3rem;
  }
  
  .search-container {
    order: 4;
    grid-column: 1 / -1;
    margin-top: var(--spacing-sm);
  }
  
  #searchInput {
    padding: var(--spacing-sm) var(--spacing-lg);
  }
  
  main {
    padding: var(--spacing-xl) var(--spacing-md);
  }
}

/* Small Mobile (<480px) */
@media screen and (max-width: 479px) {
  body {
    background: var(--gradient-primary);
  }
  
  body::before {
    opacity: 0.5;
  }
  
  .navbar__container {
    grid-template-columns: 1fr auto auto;
    padding: 0 var(--spacing-sm);
    gap: var(--spacing-sm);
  }
  
  #navbar__logo {
    order: 1;
  }
  
  #navbar__logo img {
    height: 36px;
  }
  
  .home-btn {
    order: 2;
    width: 40px;
    height: 40px;
    padding: 0;
  }
  
  .ai-btn {
    order: 3;
    width: 40px;
    height: 40px;
    padding: 0;
  }
  
  .mobile-nav-toggle {
    order: 4;
  }
  
  .search-container {
    order: 5;
    grid-column: 1 / -1;
    margin-top: var(--spacing-sm);
  }
  
  #searchInput {
    font-size: 0.875rem;
    padding: 0.75rem var(--spacing-lg);
  }
  
  #searchBtn {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
  }
  
  .mobile-nav-content {
    width: 100%;
    max-width: none;
    padding: var(--spacing-2xl) var(--spacing-lg);
  }
  
  .mobile-nav-link {
    padding: var(--spacing-md);
    font-size: 1rem;
  }
  
  main {
    padding: var(--spacing-lg) var(--spacing-sm);
  }
  
  .content-loader p {
    font-size: 1rem;
  }
  
  .loader-spinner {
    width: 60px;
    height: 60px;
  }
}

/* Landscape Mobile Optimization */
@media screen and (max-height: 600px) and (orientation: landscape) {
  .site-header {
    padding: var(--spacing-xs) 0;
  }
  
  #navbar__logo img {
    height: 32px;
  }
  
  .home-btn,
  .ai-btn {
    width: 36px;
    height: 36px;
  }
  
  .mobile-nav-content {
    padding: var(--spacing-xl) var(--spacing-lg);
  }
  
  .mobile-nav-links {
    margin-top: var(--spacing-lg);
  }
  
  .mobile-nav-link {
    padding: var(--spacing-sm) var(--spacing-lg);
    margin-bottom: var(--spacing-xs);
  }
}

/* High-DPI Screens */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
  .ai-btn,
  .home-btn,
  .premium-link {
    border-width: 1.5px;
  }
}

/* Print Styles */
@media print {
  .site-header,
  .mobile-nav,
  .content-loader {
    display: none !important;
  }
  
  body {
    background: var(--color-white) !important;
    color: var(--color-black) !important;
  }
  
  main {
    padding: 0 !important;
    margin: 0 !important;
  }
}

/* Accessibility: Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  
  html {
    scroll-behavior: auto;
  }
  
  .loader-spinner,
  .loader-spinner::after {
    animation: none;
  }
  
  .ai-btn::before,
  .premium-link::after {
    animation: none;
    display: none;
  }
}

/* Accessibility: High Contrast Mode */
@media (prefers-contrast: high) {
  :root {
    --color-primary: #0000FF;
    --color-secondary: #FF6B00;
    --color-accent: #008000;
  }
  
  .ai-btn,
  .home-btn,
  .premium-link {
    border: 3px solid currentColor;
  }
  
  .nav-link,
  .mobile-nav-link {
    border: 2px solid currentColor;
  }
}

/* Dark Mode Support */
@media (prefers-color-scheme: dark) {
  .site-header {
    background: rgba(17, 24, 39, 0.98);
    border-bottom-color: rgba(255, 255, 255, 0.1);
  }
  
  .nav-link {
    color: var(--color-gray-300);
  }
  
  .nav-link:hover {
    color: var(--color-primary-light);
  }
  
  .mobile-nav-content {
    background: var(--color-gray-900);
  }
  
  .mobile-nav-link {
    color: var(--color-gray-300);
  }
  
  .mobile-nav-link:hover {
    background: var(--color-gray-800);
  }
  
  #searchInput {
    background: var(--color-gray-800);
    border-color: var(--color-gray-700);
    color: var(--color-gray-100);
  }
  
  #searchInput::placeholder {
    color: var(--color-gray-500);
  }
  
  #searchInput:focus {
    border-color: var(--color-primary-light);
    box-shadow: 0 0 0 3px rgba(129, 140, 248, 0.1);
  }
}