/* Base Variables */
:root {
  /* Light Mode Colors */
  --bg-primary: #f8fafc;
  --bg-secondary: #f1f5f9;
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --accent-primary: #3b82f6;
  --accent-secondary: #60a5fa;
  --card-bg: rgba(255, 255, 255, 0.85);
  --card-border: rgba(255, 255, 255, 0.2);
  --card-shadow: rgba(17, 12, 46, 0.1);
  --sidebar-bg: rgba(255, 255, 255, 0.8);
  --header-bg: rgba(255, 255, 255, 0.85);
  --input-bg: rgba(255, 255, 255, 0.9);
  --input-border: rgba(203, 213, 225, 0.8);
  --search-icon: #94a3b8;
  --hover-bg: rgba(248, 250, 252, 0.8);

  /* Sizing */
  --header-height: 4rem;
  --sidebar-width: 280px;
  --card-border-radius: 12px;
  --btn-border-radius: 8px;
  --transition-speed: 0.3s;
}

.dark-mode {
  /* Dark Mode Colors */
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --accent-primary: #60a5fa;
  --accent-secondary: #3b82f6;
  --card-bg: rgba(30, 41, 59, 0.8);
  --card-border: rgba(71, 85, 105, 0.3);
  --card-shadow: rgba(0, 0, 0, 0.2);
  --sidebar-bg: rgba(15, 23, 42, 0.8);
  --header-bg: rgba(15, 23, 42, 0.8);
  --input-bg: rgba(30, 41, 59, 0.8);
  --input-border: rgba(71, 85, 105, 0.5);
  --search-icon: #64748b;
  --hover-bg: rgba(30, 41, 59, 0.8);
}

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

body {
  font-family: -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);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--card-border);
  box-shadow: 0 4px 6px -1px 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: 700;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  transition: color var(--transition-speed);
}

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

.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: 1px solid var(--input-border);
  background-color: var(--input-bg);
  color: var(--text-primary);
  font-size: 0.9rem;
  outline: none;
  transition: all var(--transition-speed);
  backdrop-filter: blur(5px);
  -webkit-backdrop-filter: blur(5px);
}

#search-input:focus {
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.3);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.theme-toggle, .github-link, .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: 1.2rem;
  transition: all var(--transition-speed);
}

.theme-toggle:hover, .github-link: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);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  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: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1rem;
  padding-left: 0.5rem;
}

.categories-list {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.category-item {
  display: flex;
  align-items: center;
  padding: 0.75rem 1rem;
  border-radius: var(--btn-border-radius);
  color: var(--text-primary);
  font-size: 0.9rem;
  font-weight: 500;
  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: 1.5rem;
  margin-right: 0.75rem;
  font-size: 1rem;
}

/* 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;
}

.main-title {
  font-size: 2.5rem;
  font-weight: 800;
  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: 600;
}

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

.category-section {
  margin-bottom: 3rem;
}

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

.category-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-right: 1rem;
  color: var(--text-primary);
  transition: color var(--transition-speed);
}

.resource-count {
  background-color: var(--accent-primary);
  color: white;
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.2rem 0.6rem;
  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);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  box-shadow: 0 4px 6px -1px var(--card-shadow);
  height: 100%;
}

.resource-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 15px -3px var(--card-shadow);
}

.resource-name {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  transition: color var(--transition-speed);
}

.resource-icon {
  margin-right: 0.75rem;
  font-size: 1.2rem;
  color: var(--accent-primary);
  transition: color var(--transition-speed);
  width: 1.5rem;
}

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

.resource-link {
  display: inline-flex;
  align-items: center;
  color: var(--accent-primary);
  font-weight: 500;
  font-size: 0.9rem;
  margin-top: auto;
  transition: color var(--transition-speed);
}

.resource-link:hover {
  color: var(--accent-secondary);
}

.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: 0.5rem 1rem;
  background-color: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--btn-border-radius);
  color: var(--text-primary);
  font-size: 0.9rem;
  font-weight: 500;
  transition: all var(--transition-speed);
}

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

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

/* Footer */
.footer {
  background-color: var(--header-bg);
  border-top: 1px solid var(--card-border);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  padding: 2rem 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;
}

/* 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;
  }
}

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

  .app-container {
    overflow-x: hidden;
  }
}

/* Animations */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

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