/* Base Variables */
:root {
  /* LEGO Theme Colors */
  --lego-red: #D01012;
  --lego-blue: #006CB7;
  --lego-yellow: #FFD500;
  --lego-green: #00AF4D;
  
  /* Light Mode Colors */
  --bg-primary: #f8f9fc;
  --bg-secondary: #f1f5f9;
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --accent-primary: var(--lego-red);
  --accent-secondary: #D93B3B;
  --card-bg: #ffffff;
  --card-border: #e2e8f0;
  --card-shadow: rgba(0, 0, 0, 0.08);
  --sidebar-bg: #ffffff;
  --header-bg: #ffffff;
  --input-bg: #f8fafc;
  --input-border: #e2e8f0;
  --search-icon: #94a3b8;
  --stud-color: var(--lego-yellow);
  --brick-shadow: rgba(0, 0, 0, 0.15);
  --hover-bg: #f1f5f9;

  /* Sizing */
  --header-height: 4.5rem;
  --sidebar-width: 280px;
  --card-border-radius: 8px;
  --btn-border-radius: 8px;
  --transition-speed: 0.3s;
  --brick-border-radius: 3px;
}

/* Color Themes */
.theme-blue {
  --accent-primary: var(--lego-blue);
  --accent-secondary: #2B89D1;
  --stud-color: var(--lego-yellow);
}

.theme-yellow {
  --accent-primary: var(--lego-yellow);
  --accent-secondary: #FFE566;
  --stud-color: var(--lego-blue);
  --text-primary: #1a1a1a;
}

.theme-green {
  --accent-primary: var(--lego-green);
  --accent-secondary: #45C67C;
  --stud-color: var(--lego-yellow);
}

/* Dark Mode */
.dark-mode {
  --bg-primary: #121212;
  --bg-secondary: #1e1e1e;
  --text-primary: #f1f5f9;
  --text-secondary: #cbd5e1;
  --card-bg: #242424;
  --card-border: #2d2d2d;
  --card-shadow: rgba(0, 0, 0, 0.3);
  --sidebar-bg: #1a1a1a;
  --header-bg: #1a1a1a;
  --input-bg: #2a2a2a;
  --input-border: #3a3a3a;
  --search-icon: #9ca3af;
  --brick-shadow: rgba(0, 0, 0, 0.5);
  --hover-bg: #2a2a2a;
}

/* General Styles */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Nunito', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 
               Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  transition: background-color var(--transition-speed), color var(--transition-speed);
}

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

a:hover {
  color: var(--accent-secondary);
}

button {
  cursor: pointer;
  background: none;
  border: none;
  outline: none;
  color: inherit;
}

/* App Container */
.app-container {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  z-index: 100;
  background-color: var(--header-bg);
  border-bottom: 2px solid var(--accent-primary);
  box-shadow: 0 4px 10px -2px var(--card-shadow);
  transition: background-color var(--transition-speed), border-color var(--transition-speed);
}

.header-content {
  max-width: 1440px;
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  transition: color var(--transition-speed);
}

.logo span {
  color: var(--accent-primary);
  margin-right: 0.25rem;
  font-weight: 900;
}

.logo-brick {
  width: 2.5rem;
  height: 1.25rem;
  background-color: var(--accent-primary);
  margin-right: 0.5rem;
  border-radius: var(--brick-border-radius);
  position: relative;
  box-shadow: 0 2px 4px var(--brick-shadow);
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  padding: 0.12rem;
  gap: 0.12rem;
}

.stud {
  width: 100%;
  height: 0.5rem;
  background-color: var(--stud-color);
  border-radius: 50%;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.1) inset;
}

.search-container {
  flex: 1;
  max-width: 500px;
  margin: 0 1rem;
}

.search-input-wrapper {
  position: relative;
  width: 100%;
}

.search-icon {
  position: absolute;
  left: 1rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--search-icon);
  transition: color var(--transition-speed);
}

#search-input {
  width: 100%;
  padding: 0.75rem 1rem 0.75rem 2.5rem;
  border-radius: var(--btn-border-radius);
  border: 2px solid var(--input-border);
  background-color: var(--input-bg);
  color: var(--text-primary);
  font-size: 0.9rem;
  font-family: inherit;
  outline: none;
  transition: all var(--transition-speed);
}

#search-input:focus {
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 2px rgba(208, 16, 18, 0.2);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.theme-toggle, .menu-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  color: var(--text-primary);
  font-size: 1.1rem;
  transition: all var(--transition-speed);
  background-color: var(--bg-secondary);
}

.theme-toggle:hover, .menu-toggle:hover {
  background-color: var(--hover-bg);
  color: var(--accent-primary);
}

.menu-toggle {
  display: none;
}

/* Main Container */
.main-container {
  display: flex;
  margin-top: var(--header-height);
  flex: 1;
}

/* Sidebar */
.sidebar {
  width: var(--sidebar-width);
  background-color: var(--sidebar-bg);
  border-right: 1px solid var(--card-border);
  height: calc(100vh - var(--header-height));
  position: fixed;
  top: var(--header-height);
  left: 0;
  overflow-y: auto;
  transition: all var(--transition-speed);
  z-index: 50;
}

.sidebar-content {
  padding: 1.5rem 1rem;
}

.sidebar-title {
  color: var(--text-secondary);
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1.25rem;
  padding-left: 0.5rem;
  font-weight: 800;
}

.categories-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.category-item {
  display: flex;
  align-items: center;
  padding: 0.75rem 1rem;
  border-radius: var(--btn-border-radius);
  color: var(--text-primary);
  font-size: 0.95rem;
  font-weight: 600;
  transition: all var(--transition-speed);
  cursor: pointer;
}

.category-item:hover {
  background-color: var(--hover-bg);
  color: var(--accent-primary);
}

.category-item.active {
  background-color: var(--accent-primary);
  color: white;
}

.category-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  margin-right: 0.75rem;
  font-size: 1rem;
  background-color: var(--bg-secondary);
  border-radius: var(--btn-border-radius);
  color: var(--accent-primary);
  transition: all var(--transition-speed);
}

.category-item.active .category-icon {
  background-color: rgba(255, 255, 255, 0.2);
  color: white;
}

/* Main Content */
.main-content {
  flex: 1;
  margin-left: var(--sidebar-width);
  padding: 2rem;
  transition: margin-left var(--transition-speed);
}

.hero-section {
  text-align: center;
  margin-bottom: 3rem;
  position: relative;
}

.hero-bricks {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.hero-brick {
  width: 3rem;
  height: 1.5rem;
  border-radius: var(--brick-border-radius);
  position: relative;
  box-shadow: 0 3px 6px var(--brick-shadow);
}

.hero-brick::before {
  content: '';
  position: absolute;
  top: -0.5rem;
  left: 0.375rem;
  width: 0.75rem;
  height: 0.5rem;
  background-color: inherit;
  border-radius: var(--brick-border-radius) var(--brick-border-radius) 0 0;
}

.hero-brick::after {
  content: '';
  position: absolute;
  top: -0.5rem;
  right: 0.375rem;
  width: 0.75rem;
  height: 0.5rem;
  background-color: inherit;
  border-radius: var(--brick-border-radius) var(--brick-border-radius) 0 0;
}

.hero-brick.red {
  background-color: var(--lego-red);
}

.hero-brick.blue {
  background-color: var(--lego-blue);
}

.hero-brick.yellow {
  background-color: var(--lego-yellow);
}

.hero-brick.green {
  background-color: var(--lego-green);
}

.main-title {
  font-size: 2.75rem;
  font-weight: 900;
  margin-bottom: 1rem;
  color: var(--text-primary);
  transition: color var(--transition-speed);
}

.main-description {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 800px;
  margin: 0 auto;
  transition: color var(--transition-speed);
}

.highlight {
  color: var(--accent-primary);
  font-weight: 800;
}

/* Resources Container */
.resources-container {
  max-width: 1200px;
  margin: 0 auto;
}

.category-section {
  margin-bottom: 3.5rem;
}

.category-header {
  display: flex;
  align-items: center;
  margin-bottom: 1.5rem;
  position: relative;
}

.category-title {
  font-size: 1.5rem;
  font-weight: 800;
  margin-right: 1rem;
  color: var(--text-primary);
  transition: color var(--transition-speed);
  display: flex;
  align-items: center;
}

.category-title-icon {
  width: 2.5rem;
  height: 2.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--accent-primary);
  color: white;
  border-radius: var(--btn-border-radius);
  margin-right: 0.75rem;
  font-size: 1.1rem;
}

.resource-count {
  background-color: var(--accent-primary);
  color: white;
  font-size: 0.8rem;
  font-weight: 700;
  padding: 0.2rem 0.7rem;
  border-radius: 1rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.resources-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.resource-card {
  background-color: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--card-border-radius);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-speed);
  box-shadow: 0 4px 8px var(--card-shadow);
  height: 100%;
  position: relative;
  overflow: hidden;
}

.resource-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 0.25rem;
  background-color: var(--accent-primary);
  transition: all var(--transition-speed);
}

.resource-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 20px var(--card-shadow);
}

.resource-card:hover::before {
  height: 0.5rem;
}

.resource-name {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  transition: color var(--transition-speed);
}

.resource-icon-wrapper {
  width: 2.75rem;
  height: 2.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--btn-border-radius);
  margin-right: 0.75rem;
  background-color: var(--bg-secondary);
}

.resource-icon {
  font-size: 1.35rem;
  color: var(--accent-primary);
  transition: color var(--transition-speed);
}

.resource-description {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 1.25rem;
  flex: 1;
}

.resource-link {
  display: inline-flex;
  align-items: center;
  padding: 0.65rem 1.25rem;
  background-color: var(--bg-secondary);
  color: var(--text-primary);
  font-weight: 600;
  font-size: 0.9rem;
  margin-top: auto;
  border-radius: var(--btn-border-radius);
  transition: all var(--transition-speed);
}

.resource-link:hover {
  background-color: var(--accent-primary);
  color: white;
}

.resource-link i {
  margin-left: 0.5rem;
  font-size: 0.8rem;
}

.back-to-top {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-top: 2rem;
  padding: 0.75rem 1.25rem;
  background-color: var(--bg-secondary);
  border-radius: var(--btn-border-radius);
  color: var(--text-primary);
  font-size: 0.9rem;
  font-weight: 600;
  transition: all var(--transition-speed);
  border: none;
}

.back-to-top:hover {
  background-color: var(--accent-primary);
  color: white;
}

.back-to-top i {
  margin-right: 0.5rem;
}

/* Footer */
.footer {
  background-color: var(--header-bg);
  border-top: 1px solid var(--card-border);
  padding: 2.5rem 0;
  margin-top: 3rem;
  transition: background-color var(--transition-speed), border-color var(--transition-speed);
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.footer-content p {
  margin-bottom: 0.5rem;
}

.footer-bricks {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.footer-brick {
  width: 2rem;
  height: 1rem;
  border-radius: var(--brick-border-radius);
  position: relative;
  box-shadow: 0 2px 4px var(--brick-shadow);
}

.footer-brick.red {
  background-color: var(--lego-red);
}

.footer-brick.blue {
  background-color: var(--lego-blue);
}

.footer-brick.yellow {
  background-color: var(--lego-yellow);
}

.footer-brick.green {
  background-color: var(--lego-green);
}

/* Mobile Styles */
@media (max-width: 992px) {
  .sidebar {
    transform: translateX(-100%);
    box-shadow: 4px 0 10px rgba(0, 0, 0, 0.1);
  }
  
  .sidebar.active {
    transform: translateX(0);
  }
  
  .main-content {
    margin-left: 0;
  }
  
  .menu-toggle {
    display: flex;
  }
  
  .resources-grid {
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  }
}

@media (max-width: 768px) {
  .header-content {
    padding: 0 1rem;
  }
  
  .search-container {
    max-width: none;
  }
  
  .main-content {
    padding: 1.5rem 1rem;
  }
  
  .main-title {
    font-size: 2rem;
  }
  
  .resources-grid {
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 1rem;
  }
  
  .hero-bricks {
    gap: 0.75rem;
  }
  
  .hero-brick {
    width: 2.5rem;
    height: 1.25rem;
  }
}

@media (max-width: 576px) {
  .search-container {
    display: none;
  }
  
  .resources-grid {
    grid-template-columns: 1fr;
  }

  .app-container {
    overflow-x: hidden;
  }
  
  .hero-section {
    margin-bottom: 2rem;
  }
}

/* Animations */
@keyframes brickBounce {
  0% { transform: translateY(0); }
  50% { transform: translateY(-5px); }
  100% { transform: translateY(0); }
}

.hero-brick {
  animation: brickBounce 3s ease-in-out infinite;
}

.hero-brick:nth-child(1) {
  animation-delay: 0s;
}

.hero-brick:nth-child(2) {
  animation-delay: 0.2s;
}

.hero-brick:nth-child(3) {
  animation-delay: 0.4s;
}

.hero-brick:nth-child(4) {
  animation-delay: 0.6s;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.resource-card {
  animation: fadeIn 0.5s ease-out forwards;
}

.resources-grid .resource-card:nth-child(2) {
  animation-delay: 0.1s;
}

.resources-grid .resource-card:nth-child(3) {
  animation-delay: 0.2s;
}

.resources-grid .resource-card:nth-child(4) {
  animation-delay: 0.3s;
}

.resources-grid .resource-card:nth-child(5) {
  animation-delay: 0.4s;
}

.resources-grid .resource-card:nth-child(6) {
  animation-delay: 0.5s;
}

.resources-grid .resource-card:nth-child(n+7) {
  animation-delay: 0.6s;
}