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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.6;
  color: #333;
  background: #f5f5f5;
}

a {
  color: #6b46c1;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* Header */
header {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  padding: 1rem 2rem;
}

.header-content {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  color: white;
  font-size: 1.5rem;
  font-weight: bold;
}

.logo:hover {
  text-decoration: none;
}

nav a {
  color: white;
  margin-left: 2rem;
  opacity: 0.9;
}

nav a:hover,
nav a.active {
  opacity: 1;
  text-decoration: none;
}

/* Main */
main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem;
  min-height: calc(100vh - 200px);
}

/* Hero */
.hero {
  text-align: center;
  padding: 3rem 0;
}

.hero h1 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}

.hero p {
  font-size: 1.2rem;
  color: #666;
}

.hero-features {
  max-width: 600px;
  margin: 1.5rem auto 0;
  text-align: left;
  background: white;
  padding: 1.5rem 2rem;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.hero-features ul {
  margin: 0.5rem 0 1rem 1.5rem;
  color: #555;
}

.hero-features li {
  margin-bottom: 0.3rem;
}

.hero-features p:last-child {
  margin-bottom: 0;
  font-weight: 500;
  color: #6b46c1;
}

/* Categories */
.categories,
.popular {
  margin: 2rem 0;
}

.categories h2,
.popular h2 {
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid #667eea;
}

.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 1rem;
}

.category-card {
  background: white;
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  transition: transform 0.2s, box-shadow 0.2s;
}

.category-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0,0,0,0.15);
  text-decoration: none;
}

.category-card h3 {
  color: #333;
  margin-bottom: 0.5rem;
}

.category-card p {
  color: #666;
  font-size: 0.9rem;
}

/* Article List */
.article-list {
  list-style: none;
}

.article-list li {
  background: white;
  margin-bottom: 0.5rem;
  padding: 1rem 1.5rem;
  border-radius: 4px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.article-list li p {
  margin-top: 0.5rem;
  color: #666;
  font-size: 0.9rem;
}

/* Section Header */
.section-header {
  margin-bottom: 2rem;
}

.section-header h1 {
  margin-bottom: 0.5rem;
}

.section-description {
  color: #666;
}

/* FAQ Article */
.faq-article {
  background: white;
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.faq-article header {
  background: none;
  padding: 0;
  margin-bottom: 1.5rem;
}

.faq-article h1 {
  color: #333;
  margin-bottom: 0.5rem;
}

.breadcrumb {
  color: #666;
  font-size: 0.9rem;
}

.breadcrumb a {
  color: #6b46c1;
}

.content {
  line-height: 1.8;
}

.content p {
  margin-bottom: 1rem;
}

.content ul,
.content ol {
  margin: 1rem 0 1rem 2rem;
}

.content li {
  margin-bottom: 0.5rem;
}

.content a {
  color: #6b46c1;
}

/* Footer */
footer {
  background: #333;
  color: #999;
  text-align: center;
  padding: 1.5rem;
  margin-top: 2rem;
}

/* Responsive */
@media (max-width: 768px) {
  .header-content {
    flex-direction: column;
    gap: 1rem;
  }

  nav a {
    margin: 0 1rem;
  }

  .hero h1 {
    font-size: 2rem;
  }

  main {
    padding: 1rem;
  }
}