/* ============================================
   VARIABLES Y RESET BASE
   ============================================ */

:root {
  /* Colores */
  --bg: #0b1223;
  --surface: #0f1a33;
  --surface-2: #121f3d;
  --border: rgba(255, 255, 255, 0.1);
  --text: #f3f6ff;
  --text-muted: #b8c2d6;
  --primary: #13c38b;
  --primary-hover: #46f0b4;
  --secondary: #36a6ff;
  --danger: #ff5b6e;
  --success: #13c38b;
  --warning: #ffc107;

  /* Tipografía */
  --font-body: 'Inter', system-ui, -apple-system, sans-serif;
  --fs-xs: 0.75rem;
  --fs-sm: 0.875rem;
  --fs-base: 1rem;
  --fs-lg: 1.125rem;
  --fs-xl: 1.25rem;
  --fs-2xl: 1.5rem;
  --fs-3xl: 1.875rem;
  --fs-4xl: 2.25rem;
  --fs-5xl: 3rem;

  /* Espaciado - Mobile First */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;

  /* Layout */
  --container-max: 1280px;
  --nav-height: 64px;
  --sidebar-width: 220px;

  /* Bordes */
  --radius-sm: 6px;
  --radius: 10px;
  --radius-lg: 14px;
  --radius-xl: 18px;
  --radius-full: 9999px;

  /* Sombras */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.25);
  --shadow-xl: 0 20px 50px rgba(0, 0, 0, 0.35);

  /* Transiciones */
  --transition-fast: 150ms ease;
  --transition: 250ms ease;
  --transition-slow: 350ms ease;

  color-scheme: dark;
}

/* Ajustes para tablets */
@media (min-width: 768px) {
  :root {
    --nav-height: 72px;
  }
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  font-size: var(--fs-base);
  line-height: 1.6;
  color: var(--text);
  background: radial-gradient(900px 500px at 20% 10%, rgba(19, 195, 139, 0.15), transparent 60%),
              radial-gradient(900px 500px at 80% 20%, rgba(54, 166, 255, 0.12), transparent 60%),
              var(--bg);
  background-attachment: fixed;
  min-height: 100vh;
  overflow-x: hidden;
}

/* Tipografía */
h1, h2, h3, h4, h5, h6 {
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

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

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

img {
  max-width: 100%;
  height: auto;
  display: block;
}

button, input, select, textarea {
  font: inherit;
  color: inherit;
}

button {
  cursor: pointer;
  border: none;
  background: none;
}

/* Focus visible */
:focus-visible {
  outline: 3px solid var(--primary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* Utilidades */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

@media (min-width: 640px) {
  .container {
    padding: 0 var(--space-5);
  }
}

@media (min-width: 1024px) {
  .container {
    padding: 0 var(--space-6);
  }
}

.section {
  padding: var(--space-8) 0;
}

@media (min-width: 768px) {
  .section {
    padding: var(--space-12) 0;
  }
}

@media (min-width: 1024px) {
  .section {
    padding: var(--space-16) 0;
  }
}

.section-gray {
  background: rgba(0, 0, 0, 0.2);
}

/* Skip link */
.skip-link {
  position: absolute;
  left: var(--space-4);
  top: var(--space-4);
  padding: var(--space-3) var(--space-5);
  background: var(--surface);
  border: 2px solid var(--primary);
  border-radius: var(--radius);
  font-weight: 700;
  transform: translateY(-150%);
  transition: transform var(--transition);
  z-index: 9999;
}

.skip-link:focus {
  transform: translateY(0);
}

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

/* Reduce motion */
@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;
  }
}

/* Asegura que el atributo HTML "hidden" SIEMPRE oculte el elemento */
[hidden] {
  display: none !important;
}