/* CSS Custom Properties */
:root {
  --color-primary: #002347; /* Navy Blue */
  --color-secondary: #AA151B; /* Spanish Red */
  --color-accent: #F1BF00; /* Spanish Yellow */
  --color-text-main: #333333;
  --color-text-muted: #666666;
  --color-bg-main: #ffffff;
  --color-bg-alt: #f4f7f6;
  --color-border: #e0e0e0;
  
  --font-body: 'Inter', system-ui, -apple-system, sans-serif;
  --font-heading: 'Playfair Display', serif;
  
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  --spacing-xl: 6rem;
  
  --radius: 8px;
  --shadow-sm: 0 2px 4px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
}

/* Dark Mode Variables */
body.dark-mode {
  --color-primary: #66aaff;
  --color-text-main: #f0f0f0;
  --color-text-muted: #a0a0a0;
  --color-bg-main: #121212;
  --color-bg-alt: #1e1e1e;
  --color-border: #333333;
}

/* Reset & Global Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  color: var(--color-text-main);
  background-color: var(--color-bg-main);
  line-height: 1.6;
  transition: background-color 0.3s ease, color 0.3s ease;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  color: var(--color-primary);
  line-height: 1.2;
  margin-bottom: var(--spacing-sm);
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.3s ease;
}

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

img {
  max-width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius);
}

/* Layout Utilities */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-sm);
}

.grid {
  display: grid;
  gap: var(--spacing-md);
}

.flex {
  display: flex;
}

/* Header & Navigation */
.site-header {
  background-color: var(--color-bg-main);
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 1000;
  padding: var(--spacing-sm) 0;
  transition: background-color 0.3s ease;
}

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

.site-logo {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.site-logo svg {
  width: 32px;
  height: 32px;
  fill: var(--color-secondary);
}

.site-logo span {
  color: var(--color-secondary);
}

.main-nav ul {
  list-style: none;
  display: flex;
  gap: var(--spacing-sm);
  align-items: center;
}

.main-nav a {
  font-weight: 500;
  padding: 0.5rem;
  display: block;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--color-primary);
}

/* Search Box & Controls */
.header-controls {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.search-form input {
  padding: 0.5rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background-color: var(--color-bg-main);
  color: var(--color-text-main);
}

.dark-mode-btn {
  background: none;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 0.5rem;
  cursor: pointer;
  color: var(--color-text-main);
}

/* Hero Section */
.hero {
  background: linear-gradient(135deg, var(--color-primary) 0%, #001224 100%);
  color: white;
  padding: var(--spacing-xl) 0;
  text-align: center;
}

.hero h1 {
  color: white;
  font-size: 3rem;
  margin-bottom: var(--spacing-sm);
}

.hero p {
  font-size: 1.25rem;
  max-width: 800px;
  margin: 0 auto var(--spacing-md);
  opacity: 0.9;
}

.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius);
  font-weight: 600;
  text-align: center;
  cursor: pointer;
  transition: all 0.3s ease;
  border: none;
}

.btn-primary {
  background-color: var(--color-secondary);
  color: white;
}

.btn-primary:hover {
  background-color: #8c1015;
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-cta {
  background-color: var(--color-accent);
  color: #000;
}

/* Categories Section */
.categories {
  padding: var(--spacing-lg) 0;
  background-color: var(--color-bg-alt);
}

.section-title {
  text-align: center;
  font-size: 2.5rem;
  margin-bottom: var(--spacing-lg);
}

.category-grid {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.category-card {
  background-color: var(--color-bg-main);
  border-radius: var(--radius);
  padding: var(--spacing-md);
  box-shadow: var(--shadow-sm);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  text-align: center;
  border-bottom: 4px solid transparent;
}

.category-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
  border-bottom-color: var(--color-secondary);
}

/* Breadcrumbs */
.breadcrumbs {
  padding: var(--spacing-sm) 0;
  background-color: var(--color-bg-alt);
  font-size: 0.9rem;
}

.breadcrumbs ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.breadcrumbs li::after {
  content: "/";
  margin-left: 0.5rem;
  color: var(--color-text-muted);
}

.breadcrumbs li:last-child::after {
  content: "";
}

/* Content Layout (TOC + Main) */
.page-layout {
  padding: var(--spacing-lg) 0;
  align-items: start;
}

.page-layout .grid {
  grid-template-columns: 1fr 300px;
}

.main-content {
  background-color: var(--color-bg-main);
  padding: var(--spacing-md);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
}

.main-content section {
  margin-top: var(--spacing-md);
}

.badge-update {
  display: inline-block;
  background-color: var(--color-accent);
  color: #000;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  font-size: 0.8rem;
  font-weight: bold;
  margin-bottom: 1rem;
}

/* Pasos numerados */
.steps {
  counter-reset: steps-counter;
  list-style: none;
  margin: var(--spacing-md) 0;
}

.steps li {
  position: relative;
  padding-left: 3rem;
  margin-bottom: var(--spacing-sm);
}

.steps li::before {
  counter-increment: steps-counter;
  content: counter(steps-counter);
  position: absolute;
  left: 0;
  top: 0;
  background-color: var(--color-primary);
  color: white;
  width: 2rem;
  height: 2rem;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
}

/* Floating TOC */
.sidebar {
  position: sticky;
  top: 100px;
}

.toc {
  background-color: var(--color-bg-alt);
  padding: var(--spacing-sm);
  border-radius: var(--radius);
  border-left: 4px solid var(--color-primary);
}

.toc h3 {
  font-size: 1.1rem;
  margin-bottom: var(--spacing-xs);
}

.toc ul {
  list-style: none;
}

.toc li.toc-h3 {
  padding-left: 1rem;
}

.toc a {
  display: block;
  padding: 0.25rem 0;
  color: var(--color-text-muted);
  font-size: 0.9rem;
  border-left: 2px solid transparent;
  padding-left: 0.5rem;
  transition: all 0.2s;
}

.toc a:hover, .toc a.active {
  color: var(--color-secondary);
  border-left-color: var(--color-secondary);
  font-weight: bold;
}

/* AdSense Placeholders & Placements */
.adsense-block {
  margin: var(--spacing-md) 0;
  text-align: center;
  background-color: var(--color-bg-alt);
  border: 1px dashed var(--color-border);
  padding: 1rem;
  color: var(--color-text-muted);
  font-size: 0.85rem;
  overflow: hidden;
}

.ad-header {
  width: 100%;
  min-height: 50px; /* mobile */
  margin: 1rem auto;
}

.ad-in-content {
  min-height: 280px;
  width: 100%;
  max-width: 336px;
  margin: var(--spacing-md) auto;
}

.ad-sidebar {
  display: none;
}

.ad-footer {
  width: 100%;
  min-height: 90px;
  margin: 1rem auto;
}

@media (min-width: 768px) {
  .ad-header { min-height: 90px; max-width: 728px; }
  .ad-footer { max-width: 970px; }
}

@media (min-width: 1024px) {
  .ad-sidebar {
    display: block;
    min-height: 600px;
    width: 100%;
    max-width: 300px;
    margin-top: var(--spacing-md);
  }
}

/* Form Styles */
.contact-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}
.contact-form input, .contact-form textarea {
  padding: 0.75rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  font-family: var(--font-body);
  background-color: var(--color-bg-main);
  color: var(--color-text-main);
}
.contact-form input:invalid, .contact-form textarea:invalid {
  border-left: 3px solid var(--color-secondary);
}
.was-validated input:invalid, .was-validated textarea:invalid {
  border-color: var(--color-secondary);
}

/* Footer */
.site-footer {
  background-color: var(--color-primary);
  color: white;
  padding: var(--spacing-lg) 0 var(--spacing-sm);
  margin-top: var(--spacing-lg);
}

.footer-grid {
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-md);
}

.footer-col h4 {
  color: white;
  margin-bottom: var(--spacing-sm);
}

.footer-col ul {
  list-style: none;
}

.footer-col a {
  color: #ccc;
}

.footer-col a:hover {
  color: white;
}

.trust-badge {
  display: inline-block;
  border: 1px solid rgba(255,255,255,0.2);
  padding: 0.5rem;
  border-radius: var(--radius);
  margin-top: 1rem;
  font-size: 0.8rem;
}

.footer-bottom {
  text-align: center;
  padding-top: var(--spacing-sm);
  border-top: 1px solid rgba(255,255,255,0.1);
  color: #ccc;
  font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 768px) {
  .nav-toggle {
    display: block;
  }
  
  .main-nav {
    display: none;
    width: 100%;
    margin-top: 1rem;
  }
  
  .main-nav.active {
    display: block;
  }
  
  .main-nav ul {
    flex-direction: column;
    gap: 0;
  }
  
  .main-nav a {
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--color-border);
  }
  
  .header-controls {
    width: 100%;
    margin-top: 1rem;
    justify-content: space-between;
  }
  
  .page-layout .grid {
    grid-template-columns: 1fr;
  }
  
  .sidebar {
    position: static;
    margin-bottom: var(--spacing-md);
    order: -1;
  }
}