/* ========================================
   VARIABLES CSS Y SISTEMA DE DISEÑO
   ======================================== */

:root {
  /* Colores del sistema de diseño */
  --color-primary: #2563EB;
  --color-primary-dark: #1E40AF;
  --color-primary-light: #3B82F6;
  --color-secondary: #64748B;
  --color-accent: #22C55E;
  --color-accent-dark: #16A34A;
  
  /* Colores de fondo y superficie */
  --color-background: #F9FAFB;
  --color-surface: #FFFFFF;
  --color-surface-elevated: #FFFFFF;
  
  /* Colores de texto */
  --color-text-primary: #0F172A;
  --color-text-secondary: #475569;
  --color-text-tertiary: #94A3B8;
  
  /* Colores de estado */
  --color-success: #22C55E;
  --color-error: #EF4444;
  --color-warning: #F59E0B;
  --color-info: #3B82F6;
  
  /* Bordes y líneas */
  --color-border: #E2E8F0;
  --color-border-hover: #CBD5E1;
  
  /* Sombras */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  
  /* Tipografía */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;
  
  /* Espaciado */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  
  /* Radios de borde */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;
  
  /* Transiciones */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);
  
  /* Z-index */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
}

/* Modo claro (explícito) */
[data-theme="light"] {
  --color-background: #F9FAFB;
  --color-surface: #FFFFFF;
  --color-surface-elevated: #F3F4F6;
  --color-text-primary: #0F172A;
  --color-text-secondary: #475569;
  --color-text-tertiary: #64748B;
  --color-border: #E2E8F0;
  --color-border-hover: #CBD5E1;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

/* Modo oscuro */
[data-theme="dark"] {
  --color-background: #0F172A;
  --color-surface: #1E293B;
  --color-surface-elevated: #334155;
  --color-text-primary: #F1F5F9;
  --color-text-secondary: #CBD5E1;
  --color-text-tertiary: #94A3B8;
  --color-border: #334155;
  --color-border-hover: #475569;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -1px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5), 0 4px 6px -2px rgba(0, 0, 0, 0.3);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.6), 0 10px 10px -5px rgba(0, 0, 0, 0.4);
}

/* ========================================
   RESET Y ESTILOS BASE
   ======================================== */

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--color-text-primary);
  background-color: var(--color-background);
  transition: background-color var(--transition-base), color var(--transition-base);
  min-height: 100vh;
  overflow-x: hidden;
}

/* ========================================
   TIPOGRAFÍA
   ======================================== */

h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-text-primary);
  margin-bottom: var(--spacing-md);
}

h1 { font-size: var(--font-size-5xl); }
h2 { font-size: var(--font-size-4xl); }
h3 { font-size: var(--font-size-3xl); }
h4 { font-size: var(--font-size-2xl); }
h5 { font-size: var(--font-size-xl); }
h6 { font-size: var(--font-size-lg); }

p {
  margin-bottom: var(--spacing-md);
  color: var(--color-text-secondary);
}

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

a:hover {
  color: var(--color-primary-dark);
}

a:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* ========================================
   UTILIDADES GENERALES
   ======================================== */

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.section {
  padding: var(--spacing-3xl) 0;
}

.section-title {
  font-size: var(--font-size-4xl);
  text-align: center;
  margin-bottom: var(--spacing-sm);
  margin-left: auto;
  margin-right: auto;
  position: relative;
  display: block;
  width: 100%;
  max-width: fit-content;
}

.section-title::after {
  content: '';
  display: block;
  width: 60px;
  height: 4px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent));
  margin: var(--spacing-md) auto 0;
  border-radius: var(--radius-full);
}

.section-subtitle {
  text-align: center;
  font-size: var(--font-size-lg);
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-2xl);
}

.subsection-title {
  font-size: var(--font-size-2xl);
  margin-bottom: var(--spacing-lg);
  color: var(--color-text-primary);
}

/* ========================================
   BOTONES
   ======================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: var(--font-size-base);
  font-weight: 600;
  border: none;
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-base);
  text-decoration: none;
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: var(--radius-full);
  background: rgba(255, 255, 255, 0.3);
  transform: translate(-50%, -50%);
  transition: width var(--transition-slow), height var(--transition-slow);
}

.btn:hover::before {
  width: 300px;
  height: 300px;
}

.btn-primary {
  background: var(--color-primary);
  color: white;
  box-shadow: var(--shadow-md);
}

.btn-primary:hover {
  background: var(--color-primary-dark);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-secondary {
  background: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

.btn-secondary:hover {
  background: var(--color-primary);
  color: white;
  transform: translateY(-2px);
}

.btn:active {
  transform: translateY(0);
}

.btn:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.btn-icon {
  transition: transform var(--transition-fast);
}

.btn:hover .btn-icon {
  transform: translateX(4px);
}

/* ========================================
   ACCESIBILIDAD
   ======================================== */

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* Reducir movimiento para usuarios que lo prefieran */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ========================================
   ANIMACIONES Y SCROLL REVEAL
   ======================================== */

[data-aos] {
  opacity: 0;
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

[data-aos].aos-animate {
  opacity: 1;
}

[data-aos="fade-up"] {
  transform: translateY(30px);
}

[data-aos="fade-up"].aos-animate {
  transform: translateY(0);
}

[data-aos="fade-down"] {
  transform: translateY(-30px);
}

[data-aos="fade-down"].aos-animate {
  transform: translateY(0);
}

[data-aos="fade-left"] {
  transform: translateX(-30px);
}

[data-aos="fade-left"].aos-animate {
  transform: translateX(0);
}

[data-aos="fade-right"] {
  transform: translateX(30px);
}

[data-aos="fade-right"].aos-animate {
  transform: translateX(0);
}

/* ========================================
   LOADING ESTADOS
   ======================================== */

.loading-screen,
.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--color-background);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-modal);
  transition: opacity var(--transition-base);
}

.loading-screen.hidden,
.loading-overlay.hidden {
  opacity: 0;
  pointer-events: none;
}

.loading-content {
  text-align: center;
}

.loading-spinner {
  width: 48px;
  height: 48px;
  border: 4px solid var(--color-border);
  border-top-color: var(--color-primary);
  border-radius: var(--radius-full);
  animation: spin 1s linear infinite;
  margin: 0 auto var(--spacing-md);
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.loading-text {
  color: var(--color-text-secondary);
  font-size: var(--font-size-lg);
}

/* ========================================
   SCROLLBAR PERSONALIZADO
   ======================================== */

::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: var(--color-background);
}

::-webkit-scrollbar-thumb {
  background: var(--color-secondary);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-text-secondary);
}

/* Firefox */
* {
  scrollbar-width: thin;
  scrollbar-color: var(--color-secondary) var(--color-background);
}