/* Reset y configuración base */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  color: #333;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.header {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
  padding: 2rem 0;
  text-align: center;
  margin-bottom: 2rem;
}

.header h1 {
  font-size: 2.5rem;
  color: #2c3e50;
  margin-bottom: 0.5rem;
}

.header p {
  color: #7f8c8d;
  font-size: 1.2rem;
}

/* Main content */
.main {
  padding: 2rem 0;
}

/* Introducción */
.intro {
  background: rgba(255, 255, 255, 0.95);
  border-radius: 20px;
  padding: 2rem;
  margin-bottom: 3rem;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.intro h2 {
  color: #2c3e50;
  font-size: 2rem;
  margin-bottom: 1rem;
  text-align: center;
}

.intro p {
  color: #555;
  margin-bottom: 2rem;
  text-align: center;
  font-size: 1.1rem;
}

/* Ejercicios */
.exercise {
  background: rgba(255, 255, 255, 0.95);
  border-radius: 20px;
  padding: 2rem;
  margin-bottom: 3rem;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.exercise h2 {
  color: #2c3e50;
  font-size: 1.8rem;
  margin-bottom: 1rem;
  border-bottom: 3px solid #667eea;
  padding-bottom: 0.5rem;
}

.exercise p {
  color: #555;
  margin-bottom: 1.5rem;
}

.exercise ul {
  margin-left: 2rem;
  margin-bottom: 1.5rem;
}

.exercise li {
  margin-bottom: 0.5rem;
  color: #555;
}

.exercise code {
  background: #f0f0f0;
  padding: 0.2rem 0.4rem;
  border-radius: 3px;
  font-family: "Courier New", monospace;
  color: #e74c3c;
}

/* Layout demos */
.layout-demo {
  margin: 2rem 0;
}

/* Basic layout */
.basic-layout {
  display: flex;
  border: 3px solid #667eea;
  border-radius: 10px;
  overflow: hidden;
  min-height: 400px;
}

.sidebar {
  background: linear-gradient(135deg, #2c3e50, #34495e);
  color: white;
  padding: 1.5rem;
  width: 250px;
  flex-shrink: 0;
}

.sidebar h3 {
  margin-bottom: 1rem;
  border-bottom: 2px solid #667eea;
  padding-bottom: 0.5rem;
}

.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.sidebar-link {
  color: white;
  text-decoration: none;
  padding: 0.5rem;
  border-radius: 5px;
  transition: background 0.3s ease;
}

.sidebar-link:hover {
  background: rgba(102, 126, 234, 0.3);
}

.content {
  flex: 1;
  padding: 1.5rem;
  background: white;
}

.content h2 {
  color: #2c3e50;
  margin-bottom: 1rem;
}

.content p {
  color: #555;
  margin-bottom: 1rem;
}

/* Full layout */
.full-layout {
  border: 3px solid #27ae60;
  border-radius: 10px;
  overflow: hidden;
  background: white;
}

.page-header {
  background: linear-gradient(135deg, #27ae60, #2ecc71);
  color: white;
  padding: 1rem 2rem;
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.header-nav {
  display: flex;
  gap: 2rem;
}

.header-link {
  color: white;
  text-decoration: none;
  padding: 0.5rem 1rem;
  border-radius: 5px;
  transition: background 0.3s ease;
}

.header-link:hover {
  background: rgba(255, 255, 255, 0.2);
}

.main-container {
  display: flex;
  min-height: 500px;
}

.page-sidebar {
  background: linear-gradient(135deg, #34495e, #2c3e50);
  color: white;
  padding: 1.5rem;
  width: 250px;
  flex-shrink: 0;
}

.page-content {
  flex: 1;
  padding: 1.5rem;
}

.content-section h2 {
  color: #2c3e50;
  margin-bottom: 1rem;
}

.content-section p {
  color: #555;
  margin-bottom: 2rem;
}

.cards-grid {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.content-card {
  background: #f8f9fa;
  padding: 1.5rem;
  border-radius: 10px;
  flex: 1;
  min-width: 200px;
  border: 1px solid #e0e0e0;
}

.content-card h3 {
  color: #2c3e50;
  margin-bottom: 1rem;
}

.content-card p {
  color: #555;
}

.page-footer {
  background: linear-gradient(135deg, #e74c3c, #c0392b);
  color: white;
  padding: 1rem 2rem;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-links {
  display: flex;
  gap: 1rem;
}

.footer-links a {
  color: white;
  text-decoration: none;
}

/* Responsive layout */
.responsive-layout {
  border: 3px solid #9b59b6;
  border-radius: 10px;
  overflow: hidden;
  background: white;
}

.responsive-header {
  background: linear-gradient(135deg, #9b59b6, #8e44ad);
  color: white;
  padding: 1rem 2rem;
}

.responsive-container {
  display: flex;
  min-height: 400px;
}

.responsive-sidebar {
  background: linear-gradient(135deg, #95a5a6, #7f8c8d);
  color: white;
  padding: 1.5rem;
  width: 200px;
  flex-shrink: 0;
}

.responsive-content {
  flex: 1;
  padding: 1.5rem;
}

.responsive-cards {
  display: flex;
  gap: 1rem;
  margin-top: 2rem;
}

.responsive-card {
  background: #f8f9fa;
  padding: 1.5rem;
  border-radius: 10px;
  flex: 1;
  border: 1px solid #e0e0e0;
}

.responsive-footer {
  background: linear-gradient(135deg, #f39c12, #e67e22);
  color: white;
  padding: 1rem 2rem;
  text-align: center;
}

.menu-toggle {
  background: none;
  border: none;
  color: white;
  font-size: 1.5rem;
  cursor: pointer;
  display: none;
}

/* Website layout */
.website-layout {
  border: 3px solid #1abc9c;
  border-radius: 10px;
  overflow: hidden;
  background: white;
}

.website-header {
  background: linear-gradient(135deg, #1abc9c, #16a085);
  color: white;
  padding: 1rem 2rem;
}

.header-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

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

.website-nav {
  display: flex;
  gap: 2rem;
}

.nav-link {
  color: white;
  text-decoration: none;
  padding: 0.5rem 1rem;
  border-radius: 5px;
  transition: background 0.3s ease;
}

.nav-link:hover {
  background: rgba(255, 255, 255, 0.2);
}

.website-container {
  display: flex;
  min-height: 600px;
}

.website-sidebar {
  background: #f8f9fa;
  padding: 1.5rem;
  width: 250px;
  flex-shrink: 0;
  border-right: 1px solid #e0e0e0;
}

.sidebar-widget {
  margin-bottom: 2rem;
}

.sidebar-widget h3 {
  color: #2c3e50;
  margin-bottom: 1rem;
  border-bottom: 2px solid #1abc9c;
  padding-bottom: 0.5rem;
}

.category-list,
.popular-list {
  list-style: none;
}

.category-list li,
.popular-list li {
  margin-bottom: 0.5rem;
}

.category-list a,
.popular-list a {
  color: #555;
  text-decoration: none;
  padding: 0.3rem 0;
  display: block;
  transition: color 0.3s ease;
}

.category-list a:hover,
.popular-list a:hover {
  color: #1abc9c;
}

.website-content {
  flex: 1;
  padding: 2rem;
}

.blog-post {
  margin-bottom: 3rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid #e0e0e0;
}

.blog-post:last-child {
  border-bottom: none;
}

.blog-post h2 {
  color: #2c3e50;
  margin-bottom: 0.5rem;
}

.post-meta {
  color: #7f8c8d;
  font-size: 0.9rem;
  margin-bottom: 1rem;
}

.blog-post p {
  color: #555;
  margin-bottom: 1rem;
}

.website-footer {
  background: linear-gradient(135deg, #34495e, #2c3e50);
  color: white;
  padding: 2rem;
}

.footer-container {
  display: flex;
  justify-content: space-between;
  gap: 2rem;
}

.footer-section h3 {
  margin-bottom: 1rem;
  color: #1abc9c;
}

.footer-section p {
  margin-bottom: 0.5rem;
  opacity: 0.9;
}

.social-links {
  display: flex;
  gap: 1rem;
}

.social-link {
  color: white;
  text-decoration: none;
  padding: 0.5rem 1rem;
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 5px;
  transition: all 0.3s ease;
}

.social-link:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.5);
}

/* Footer */
.footer {
  background: rgba(44, 62, 80, 0.95);
  color: white;
  text-align: center;
  padding: 2rem 0;
  margin-top: 3rem;
}

.btn-back {
  display: inline-block;
  background: linear-gradient(135deg, #667eea, #764ba2);
  color: white;
  text-decoration: none;
  padding: 0.8rem 1.5rem;
  border-radius: 25px;
  margin-top: 1rem;
  transition: all 0.3s ease;
}

.btn-back:hover {
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

/* Responsive */
@media (max-width: 768px) {
  .header h1 {
    font-size: 2rem;
  }

  .exercise {
    padding: 1.5rem;
  }

  .basic-layout,
  .main-container,
  .responsive-container,
  .website-container {
    flex-direction: column;
  }

  .sidebar,
  .page-sidebar,
  .responsive-sidebar,
  .website-sidebar {
    width: 100%;
  }

  .header-content,
  .footer-content,
  .header-container,
  .footer-container {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }

  .header-nav,
  .website-nav {
    flex-direction: column;
    gap: 0.5rem;
  }

  .cards-grid,
  .responsive-cards {
    flex-direction: column;
  }

  .menu-toggle {
    display: block;
  }

  .footer-links {
    flex-direction: column;
    gap: 0.5rem;
  }

  .social-links {
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 10px;
  }

  .header h1 {
    font-size: 1.5rem;
  }

  .exercise h2 {
    font-size: 1.5rem;
  }

  .content,
  .page-content,
  .responsive-content,
  .website-content {
    padding: 1rem;
  }

  .sidebar,
  .page-sidebar,
  .responsive-sidebar,
  .website-sidebar {
    padding: 1rem;
  }

  .page-header,
  .responsive-header,
  .website-header {
    padding: 1rem;
  }

  .page-footer,
  .responsive-footer,
  .website-footer {
    padding: 1rem;
  }
}