/* =====================================================
   SERENA CSS AHREEEEE
   ===================================================== */

/* =========================
   Design Tokens 
   ========================= */
:root {
  /* Paleta de colores  nashisxxx */
  --bg-0: #d9f0ff;
  --bg-1: #99d0f4;
  --bg-2: #6d9cb9;
  --bg-3: #4a7a9a;
  
  --ink-0: #0d1b24;
  --ink-1: #2c4352;
  --ink-2: #416073;
  --ink-3: #5c7a8a;
  
  /* Glass Morphism pq si */
  --glass-bg: rgba(255, 255, 255, 0.35);
  --glass-brd: rgba(255, 255, 255, 0.45);
  --glass-highlight: rgba(255, 255, 255, 0.15);
  
  /* cartas bonitas */
  --card-bg: rgba(255, 255, 255, 0.82);
  --card-brd: rgba(255, 255, 255, 0.6);
  --card-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
  --header-h: 82px;
  
  /* gradiantes ndeah */
  --gradient-primary: linear-gradient(135deg, var(--bg-1) 0%, var(--bg-2) 100%);
  --gradient-dark: linear-gradient(135deg, var(--ink-1) 0%, #203744 100%);
  --gradient-card: linear-gradient(145deg, rgba(255,255,255,0.9), rgba(255,255,255,0.7));
  
  /* sistema de radio */
  --r-xs: 8px;
  --r-sm: 12px;
  --r-md: 18px;
  --r-lg: 28px;
  --r-xl: 40px;
  --r-pill: 999px;
  
  /* sombreado */
  --sh-soft: 0 4px 20px rgba(0, 0, 0, 0.05);
  --sh-1: 0 10px 30px rgba(0, 0, 0, 0.08);
  --sh-2: 0 16px 44px rgba(0, 0, 0, 0.12);
  --sh-3: 0 24px 60px rgba(0, 0, 0, 0.15);
  --sh-inner: inset 0 1px 0 rgba(255, 255, 255, 0.7);
  --sh-elevated: 0 20px 50px rgba(0, 0, 0, 0.1);
  
  /* layout */
  --w: min(1200px, calc(100% - 64px));
  --w-narrow: min(800px, calc(100% - 48px));
  
  /*  transision */
  --ease: cubic-bezier(0.2, 0.8, 0.2, 1);
  --ease-bounce: cubic-bezier(0.34, 1.56, 0.64, 1);
  --ease-smooth: cubic-bezier(0.4, 0, 0.2, 1);
  --t: 300ms var(--ease);
  --t-medium: 200ms var(--ease);
  --t-fast: 140ms var(--ease);
  --t-slow: 500ms var(--ease-smooth);
  
  /* espaciado */
  --space-xs: 8px;
  --space-sm: 12px;
  --space-md: 20px;
  --space-lg: 32px;
  --space-xl: 48px;
  --space-xxl: 80px;
  
  /* Typography Scale */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-md: 1.125rem;
  --text-lg: 1.25rem;
  --text-xl: 1.5rem;
  --text-2xl: 2rem;
  --text-3xl: 2.5rem;
  --text-4xl: clamp(2.2rem, 4vw, 3.5rem);
  --text-5xl: clamp(2.5rem, 5vw, 4rem);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 64px);
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  color: var(--ink-1);
  background: linear-gradient(180deg, var(--bg-0), #eef8ff 45%, var(--bg-1));
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

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

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

section {
  scroll-margin-top: 120px;
  position: relative;
}

/* decoracion */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: 
    radial-gradient(circle at 20% 80%, rgba(153, 208, 244, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(109, 156, 185, 0.05) 0%, transparent 50%);
  z-index: -1;
  pointer-events: none;
}

/* =========================
   Header 
   ========================= */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-sm) var(--space-lg);
  background: linear-gradient(135deg, var(--bg-1), var(--bg-2));
  box-shadow: var(--sh-1);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--glass-brd);
  min-height: var(--header-h);
}

.header-serena {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  transition: transform var(--t);
}

.header-serena:hover {
  transform: translateX(4px);
}

.header-serena img {
  height: 46px;
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
}

.header-serena h1 {
  margin: 0;
  font-family: 'Times New Roman', serif;
  font-weight: 200;
  font-size: var(--text-3xl);
  color: var(--ink-0);
  letter-spacing: -0.5px;
  text-shadow: 0 1px 2px rgba(255, 255, 255, 0.3);
}

/* nav glassmor*/
.serena-nav ul {
  list-style: none;
  margin: 0;
  padding: var(--space-xs) var(--space-sm);
  display: flex;
  gap: var(--space-xs);
  background: var(--glass-bg);
  border: 1px solid var(--glass-brd);
  border-radius: var(--r-pill);
  backdrop-filter: blur(20px) saturate(180%);
  box-shadow: 
    var(--sh-soft),
    var(--sh-inner),
    0 0 0 1px var(--glass-highlight) inset;
}

.serena-nav a {
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--r-pill);
  font-weight: 600;
  font-size: var(--text-sm);
  transition: all var(--t);
  position: relative;
  overflow: hidden;
  display: block; /* Añadido para mejor comportamiento */
  z-index: 1; /* FIX: Asegura que esté por encima del fondo */
}

.serena-nav a::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(180, 212, 234, 0.3), transparent);
  transition: left 0.6s var(--ease);
  z-index: -1; /* FIX: Envía el fondo detrás del texto */
}

.serena-nav a:hover::before {
  left: 100%;
}

.serena-nav a:hover {
  background: rgba(180, 212, 234, 0.7);
  transform: translateY(-2px);
  box-shadow: var(--sh-soft);
  z-index: 2; /* FIX: Eleva el elemento en hover */
}

.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  padding: 10px 14px;
  border-radius: var(--r-pill);
  border: 1px solid var(--glass-brd);
  background: var(--glass-bg);
  cursor: pointer;
  box-shadow: var(--sh-soft);
  transition: all var(--t-fast);
  color: var(--ink-0);
  font-weight: 700;
  font-size: var(--text-sm);
}

.nav-ico {
  display: grid;
  gap: 5px;
}

.nav-ico span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--ink-0);
  border-radius: 10px;
  transition: transform var(--t-fast), opacity var(--t-fast);
}

.nav-label {
  letter-spacing: 0.3px;
}

.nav-toggle:active {
  transform: scale(0.96);
}

.nav-open .nav-ico span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.nav-open .nav-ico span:nth-child(2) {
  opacity: 0;
}

.nav-open .nav-ico span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* =========================
   Promo
   ========================= */
.promocion {
  background: linear-gradient(90deg, rgba(215, 233, 246, 0.9), rgba(200, 225, 242, 0.9));
  border-bottom: 1px solid rgba(44, 67, 82, 0.1);
  position: sticky;
  top: var(--header-h);
  z-index: 90;
  overflow: hidden;
}

.promocion::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
  animation: shine 3s infinite;
}

@keyframes shine {
  0% { left: -100%; }
  100% { left: 100%; }
}

.promocion span {
  width: var(--w);
  margin: auto;
  display: block;
  text-align: center;
  padding: var(--space-sm) 0;
  font-weight: 700;
  font-size: var(--text-sm);
  color: var(--ink-1);
  position: relative;
  z-index: 1;
}

/* =========================
   Hero 
   ========================= */
.hero {
  width: var(--w);
  margin: auto;
  padding: var(--space-xxl) 0;
  text-align: center;
  position: relative;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -60px;
  left: 50%;
  transform: translateX(-50%);
  width: 120px;
  height: 4px;
  background: var(--gradient-primary);
  border-radius: var(--r-pill);
}

.hero h2 {
  font-size: var(--text-5xl);
  margin: 0;
  color: var(--ink-0);
  line-height: 1.1;
  font-weight: 300;
  background: linear-gradient(135deg, var(--ink-0) 0%, var(--ink-2) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--space-md);
}

.hero p {
  max-width: 60ch;
  margin: var(--space-md) auto var(--space-xl);
  color: var(--ink-2);
  font-size: var(--text-lg);
  line-height: 1.7;
}

.hero .cta {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-xl);
  border-radius: var(--r-pill);
  background: var(--gradient-dark);
  color: white;
  font-weight: 700;
  font-size: var(--text-md);
  box-shadow: var(--sh-2);
  transition: all var(--t);
  position: relative;
  overflow: hidden;
  border: none;
  cursor: pointer;
}

.hero .cta::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.6s var(--ease);
}

.hero .cta:hover::before {
  left: 100%;
}

.hero .cta:hover {
  transform: translateY(-4px) scale(1.02);
  box-shadow: var(--sh-3);
}

/* =========================
   Qué es Serena
   ========================= */
.que-es-serena {
  width: var(--w);
  margin: var(--space-xxl) auto;
  display: grid;
  gap: var(--space-lg);
  text-align: center;
}

.que-es-serena h2 {
  font-size: var(--text-4xl);
  color: var(--ink-0);
  font-weight: 300;
}

.que-es-intro {
  margin: 0 auto;
  max-width: 70ch;
  color: var(--ink-2);
  font-size: var(--text-lg);
}

.que-es-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-lg);
}

.que-es-card {
  background: var(--gradient-card);
  padding: var(--space-lg);
  border-radius: var(--r-lg);
  box-shadow: var(--sh-1);
  border: 1px solid transparent;
  text-align: left;
  display: grid;
  gap: var(--space-sm);
  line-height: 1.7;
  position: relative;
  overflow: hidden;
  transition: all var(--t);
}

.que-es-card h3 {
  margin: 0;
  color: var(--ink-0);
  font-weight: 700;
}

.que-es-card p {
  margin: 0;
  color: var(--ink-2);
}

.que-es-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity var(--t);
}

.que-es-card:hover::before {
  opacity: 1;
}

.que-es-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--sh-elevated);
  border-color: var(--glass-brd);
}

/* =========================
   Countdown Demo
   ========================= */
.countdown {
  width: var(--w);
  margin: var(--space-lg) auto var(--space-xl);
  position: relative;
}

.countdown-inner {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  align-items: center;
  gap: var(--space-lg);
  padding: var(--space-lg);
  background: linear-gradient(135deg, rgba(255,255,255,0.88), rgba(223,239,251,0.95));
  border-radius: var(--r-xl);
  box-shadow: var(--sh-2);
  border: 1px solid rgba(109, 156, 185, 0.2);
  backdrop-filter: blur(8px);
}

.countdown-label {
  text-transform: uppercase;
  letter-spacing: 0.6px;
  font-weight: 700;
  color: var(--ink-2);
  font-size: var(--text-sm);
  margin-bottom: var(--space-xs);
}

.countdown-title {
  font-size: var(--text-2xl);
  color: var(--ink-0);
  font-weight: 300;
}

.countdown-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(70px, 1fr));
  gap: var(--space-sm);
}

.count-item {
  background: var(--gradient-card);
  border: 1px solid rgba(109, 156, 185, 0.15);
  border-radius: var(--r-lg);
  padding: var(--space-md);
  text-align: center;
  box-shadow: var(--sh-soft);
}

.count-item span {
  display: block;
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 800;
  color: var(--ink-0);
}

.count-item small {
  display: block;
  margin-top: 4px;
  font-size: var(--text-sm);
  letter-spacing: 0.3px;
  color: var(--ink-2);
}

/* =========================
   Problema 
   ========================= */
.problema {
  width: var(--w);
  margin: var(--space-xxl) auto;
  text-align: center;
}

.problema-intro {
  max-width: 70ch;
  margin: 0 auto var(--space-xl);
  font-size: var(--text-lg);
  color: var(--ink-2);
}

.problema-boxes {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-lg);
  margin-top: var(--space-xl);
}

.problema-box {
  padding: var(--space-lg);
  border-radius: var(--r-lg);
  background: var(--gradient-card);
  box-shadow: var(--sh-1);
  font-weight: 600;
  transition: all var(--t);
  border: 1px solid transparent;
  position: relative;
  overflow: hidden;
  text-align: left;
  display: grid;
  gap: var(--space-sm);
}

.problema-box::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity var(--t);
}

.problema-box:hover::before {
  opacity: 1;
}

.problema-box:hover {
  transform: translateY(-6px);
  box-shadow: var(--sh-elevated);
  border-color: var(--glass-brd);
}

.problema-box h3 {
  font-size: var(--text-lg);
  color: var(--ink-0);
  margin: 0;
}

.problema-box p {
  margin: 0;
  font-weight: 500;
  color: var(--ink-2);
  line-height: 1.6;
}

.stat-source {
  font-size: var(--text-xs);
  letter-spacing: 0.5px;
  text-transform: uppercase;
  color: var(--ink-3);
}

/* =========================
   Para quién 
   ========================= */
.para-quien {
  width: var(--w);
  margin: var(--space-xxl) auto;
  display: grid;
  gap: var(--space-lg);
  text-align: center;
}

.para-quien h2 {
  color: var(--ink-0);
  font-weight: 300;
  font-size: var(--text-4xl);
}

.para-quien-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-lg);
}

.para-quien-card {
  background: var(--gradient-card);
  padding: var(--space-xl);
  border-radius: var(--r-xl);
  box-shadow: var(--sh-1);
  border: 1px solid transparent;
  text-align: left;
  display: grid;
  gap: var(--space-sm);
  line-height: 1.7;
  transition: all var(--t);
  position: relative;
  overflow: hidden;
}

.para-quien-card::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 80% 20%, rgba(153, 208, 244, 0.15), transparent 55%);
  opacity: 0;
  transition: opacity var(--t);
  z-index: 0;
}

.para-quien-card h3 {
  margin: 0;
  color: var(--ink-0);
  font-weight: 700;
  position: relative;
  z-index: 1;
}

.para-quien-card p {
  margin: 0;
  color: var(--ink-2);
  position: relative;
  z-index: 1;
}

.para-quien-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--sh-elevated);
  border-color: var(--glass-brd);
}

.para-quien-card:hover::after {
  opacity: 1;
}

/* =========================
   Piloto 
   ========================= */
.piloto {
  width: var(--w);
  margin: var(--space-xxl) auto;
  padding: var(--space-xl);
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.9), rgba(217, 240, 255, 0.9));
  border-radius: var(--r-xl);
  box-shadow: var(--sh-1);
  text-align: center;
  border: 1px solid rgba(109, 156, 185, 0.25);
}

.piloto h2 {
  color: var(--ink-0);
  font-weight: 300;
  font-size: var(--text-4xl);
  margin-bottom: var(--space-sm);
}

.piloto-intro {
  max-width: 70ch;
  margin: 0 auto var(--space-lg);
  color: var(--ink-2);
  font-size: var(--text-lg);
}

.piloto-lista {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-sm);
}

.piloto-lista li {
  padding: var(--space-md);
  background: white;
  border-radius: var(--r-lg);
  border: 1px solid rgba(109, 156, 185, 0.2);
  color: var(--ink-1);
  font-weight: 700;
  box-shadow: var(--sh-soft);
}

/* =========================
   Confidencialidad 
   ========================= */
.confidencialidad {
  width: var(--w);
  margin: var(--space-xxl) auto;
  padding: var(--space-xl);
  background: linear-gradient(135deg, var(--bg-2), var(--bg-3));
  border-radius: var(--r-xl);
  color: white;
  box-shadow: var(--sh-2);
  position: relative;
  overflow: hidden;
}

.confidencialidad::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 25% 25%, rgba(255, 255, 255, 0.14), transparent 45%), radial-gradient(circle at 80% 70%, rgba(255, 255, 255, 0.1), transparent 40%);
  opacity: 0.8;
}

.confidencialidad h2 {
  position: relative;
  z-index: 1;
  font-weight: 300;
  font-size: var(--text-4xl);
  margin-bottom: var(--space-sm);
}

.confidencialidad p {
  position: relative;
  z-index: 1;
  margin: 0 0 var(--space-sm);
  color: rgba(255, 255, 255, 0.92);
  line-height: 1.7;
  font-size: var(--text-md);
}

/* =========================
   Cómo funciona 
   ========================= */
.como-funciona {
  background: linear-gradient(180deg, var(--bg-1), rgba(153, 208, 244, 0.6));
  padding: var(--space-xxl) 0;
  position: relative;
}

.como-funciona::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: 
    radial-gradient(circle at 30% 20%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 70% 80%, rgba(255, 255, 255, 0.05) 0%, transparent 50%);
  pointer-events: none;
}

.como-funciona h2 {
  text-align: center;
  margin-bottom: var(--space-xl);
  color: var(--ink-0);
  font-weight: 300;
  font-size: var(--text-4xl);
}

.pasos {
  width: var(--w);
  margin: auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-lg);
  position: relative;
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

.paso {
  background: var(--card-bg);
  border: 1px solid var(--card-brd);
  border-radius: var(--r-xl);
  padding: var(--space-xl);
  text-align: center;
  box-shadow: var(--sh-1);
  opacity: 0;
  animation: fadeUp 700ms var(--ease) forwards;
  transition: all var(--t);
  position: relative;
  overflow: hidden;
  z-index: 1; /* FIX: Asegura que el contenido esté visible */
}

.paso::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--gradient-primary);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--t-slow);
  z-index: 1; /* FIX: Asegura que la línea esté sobre el fondo */
}

.paso:hover::before {
  transform: scaleX(1);
}

.paso:nth-child(1) { animation-delay: 0ms; }
.paso:nth-child(2) { animation-delay: 120ms; }
.paso:nth-child(3) { animation-delay: 240ms; }
.paso:nth-child(4) { animation-delay: 360ms; }

.paso:hover {
  transform: translateY(-8px);
  box-shadow: var(--sh-3);
  
}

.paso h3 {
  transition: var(--t);
  margin-bottom: var(--space-sm);
  color: var(--ink-1);
  position: relative;
  z-index: 2; 
}

.paso:hover h3 {
  color: var(--ink-0);
  letter-spacing: 0.3px;
}

.paso-numero {
  width: 56px;
  height: 56px;
  margin: 0 auto var(--space-md);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--gradient-primary);
  color: white;
  font-weight: 800;
  font-size: var(--text-xl);
  transition: all var(--t);
  box-shadow: var(--sh-soft);
  position: relative;
  z-index: 2; 
}

.paso:hover .paso-numero {
  transform: scale(1.1);
  box-shadow: var(--sh-2);
}


.paso > *:not(.paso-numero):not(h3) {
  position: relative;
  z-index: 2; 
}


@media (min-width: 900px) {
  .paso:not(:last-child)::after {
    content: "";
    position: absolute;
    top: 50%;
    right: -14%;
    width: 28%;
    height: 2px;
    background: linear-gradient(to right, rgba(109, 156, 185, 0.3), rgba(109, 156, 185, 0.8), rgba(109, 156, 185, 0.3));
    z-index: 0;
  }
}


@media (max-width: 899px) {
  .paso {
    padding-top: 52px;
  }
  
  .paso::before {
    content: "";
    position: absolute;
    top: 0;
    left: 50%;
    width: 2px;
    height: 32px;
    background: linear-gradient(to bottom, rgba(109, 156, 185, 0.2), rgba(109, 156, 185, 0.8));
    transform: translateX(-50%);
  }
  
  .paso:first-child::before {
    display: none;
  }
}

/* =========================
   Beneficios 
   ========================= */
.beneficios {
  width: var(--w);
  margin: var(--space-xxl) auto;
  text-align: center;
}

.beneficios h2 {
  color: var(--ink-0);
  font-weight: 300;
  font-size: var(--text-4xl);
  margin-bottom: var(--space-md);
}

.beneficios-grid {
  margin-top: var(--space-xl);
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-lg);
}

.beneficio {
  background: var(--gradient-card);
  padding: var(--space-xl);
  border-radius: var(--r-xl);
  box-shadow: var(--sh-1);
  transition: all var(--t);
  border: 1px solid transparent;
  position: relative;
  overflow: hidden;
  z-index: 1;
}

.beneficio::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at top right, rgba(153, 208, 244, 0.1), transparent 70%);
  opacity: 0;
  transition: opacity var(--t);
  z-index: -1; /* FIX: Envía el efecto de fondo detrás del contenido */
}

.beneficio:hover::after {
  opacity: 1;
}

.beneficio:hover {
  transform: translateY(-6px) scale(1.02);
  box-shadow: var(--sh-elevated);
  border-color: var(--glass-brd);
}

/* =========================
   Info OMS 
   ========================= */
.info {
  background: linear-gradient(135deg, var(--bg-2), #5f8da8);
  padding: var(--space-xl) 0;
  position: relative;
  overflow: hidden;
}

.info::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: 
    radial-gradient(circle at 20% 30%, rgba(255, 255, 255, 0.1) 0%, transparent 40%),
    radial-gradient(circle at 80% 70%, rgba(255, 255, 255, 0.05) 0%, transparent 40%);
}

.infobox {
  width: var(--w-narrow);
  margin: auto;
  padding: var(--space-xl);
  text-align: center;
  background: rgba(153, 208, 244, 0.9);
  border-radius: var(--r-xl);
  box-shadow: var(--sh-2);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.3);
  position: relative;
  z-index: 1;
}

/* =========================
   Objetivo
   ========================= */
.objetivo {
  padding: var(--space-xxl) 0;
  background: linear-gradient(180deg, transparent, rgba(153, 208, 244, 0.1) 30%, transparent);
}

.objetivo h2 {
  text-align: center;
  color: var(--ink-0);
  font-weight: 300;
  font-size: var(--text-4xl);
  margin-bottom: var(--space-md);
}

.objetivo-grid {
  width: var(--w);
  margin: var(--space-xl) auto 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-lg);
}

.objetivo-card {
  background: var(--gradient-card);
  padding: var(--space-xl);
  border-radius: var(--r-xl);
  box-shadow: var(--sh-1);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.5);
  line-height: 1.7;
  display: grid;
  gap: var(--space-sm);
}

.objetivo-card h3 {
  margin: 0;
  color: var(--ink-0);
  font-weight: 700;
}

.objetivo-card p {
  margin: 0;
  color: var(--ink-2);
}

/* =========================
   Por qué Serena
   ========================= */
.por-que-serena {
  width: var(--w);
  margin: var(--space-xxl) auto;
  padding: var(--space-xl);
  background: var(--gradient-card);
  border-radius: var(--r-xl);
  box-shadow: var(--sh-1);
  border: 1px solid rgba(255, 255, 255, 0.5);
  backdrop-filter: blur(8px);
}

.por-que-serena h2 {
  text-align: center;
  color: var(--ink-0);
  font-weight: 300;
  font-size: var(--text-4xl);
  margin-bottom: var(--space-lg);
}

.razones-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-lg);
}

.razon {
  background: white;
  border-radius: var(--r-lg);
  padding: var(--space-lg);
  box-shadow: var(--sh-soft);
  border: 1px solid rgba(109, 156, 185, 0.2);
  display: grid;
  gap: var(--space-sm);
}

.razon h3 {
  margin: 0;
  color: var(--ink-0);
  font-weight: 700;
  font-size: var(--text-lg);
}

.razon p {
  margin: 0;
  color: var(--ink-2);
}

/* =========================
   Contacto 
   ========================= */
.contacto {
  padding: var(--space-xxl) 0;
  background: linear-gradient(180deg, transparent, rgba(217, 240, 255, 0.3) 100%);
}

.contacto h2 {
  color: var(--ink-0);
  font-weight: 300;
  font-size: var(--text-4xl);
}

.contacto-intro {
  width: var(--w);
  margin: auto;
  text-align: center;
  margin-bottom: var(--space-md);
}

.contacto-box {
  width: min(800px, calc(100% - 48px));
  margin: var(--space-xl) auto 0;
  background: var(--gradient-card);
  border-radius: var(--r-xl);
  box-shadow: var(--sh-2);
  border: 1px solid rgba(255, 255, 255, 0.6);
  backdrop-filter: blur(10px);
  padding: var(--space-xl);
  position: relative;
}

.contacto-toggle {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.contacto-switch {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-sm);
  background: rgba(109, 156, 185, 0.12);
  padding: 6px;
  border-radius: var(--r-pill);
  border: 1px solid rgba(109, 156, 185, 0.2);
}

.contacto-switch label {
  text-align: center;
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--r-pill);
  cursor: pointer;
  font-weight: 800;
  letter-spacing: 0.4px;
  text-transform: uppercase;
  font-size: var(--text-sm);
  transition: all var(--t);
  color: var(--ink-2);
  background: rgba(255, 255, 255, 0.8);
}

.contacto-switch label:focus-visible {
  outline: 2px solid var(--ink-0);
  outline-offset: 2px;
}

#contacto-opcion-correo:checked ~ .contacto-switch label[for="contacto-opcion-correo"],
#contacto-opcion-whatsapp:checked ~ .contacto-switch label[for="contacto-opcion-whatsapp"] {
  background: var(--gradient-dark);
  color: white;
  box-shadow: var(--sh-2);
}

.contacto-panels {
  margin-top: var(--space-lg);
}

.contacto-panels .contacto-card {
  display: none;
}

#contacto-opcion-correo:checked ~ .contacto-panels .panel-correo {
  display: grid;
}

#contacto-opcion-whatsapp:checked ~ .contacto-panels .panel-whatsapp {
  display: grid;
}

.contacto-card {
  background: var(--gradient-card);
  padding: var(--space-xl);
  border-radius: var(--r-xl);
  box-shadow: var(--sh-2);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.6);
  display: grid;
  gap: var(--space-md);
  align-content: start;
}

.contacto-card h3 {
  margin: 0;
  color: var(--ink-0);
  font-size: var(--text-2xl);
  font-weight: 700;
}

.contacto-card p {
  margin: 0;
  color: var(--ink-2);
}

.contacto-form {
  width: 100%;
  margin: 0;
  display: grid;
  gap: var(--space-md);
}

.contacto-form input,
.contacto-form select,
.contacto-form textarea {
  padding: var(--space-md);
  border-radius: var(--r-md);
  border: 1px solid rgba(109, 156, 185, 0.3);
  background: rgba(255, 255, 255, 0.9);
  font-family: inherit;
  font-size: var(--text-base);
  transition: all var(--t-fast);
}

.contacto-form input:focus,
.contacto-form select:focus,
.contacto-form textarea:focus {
  outline: none;
  border-color: var(--bg-2);
  box-shadow: 0 0 0 3px rgba(109, 156, 185, 0.2);
  background: white;
}

.contacto-form button {
  margin-top: var(--space-sm);
  padding: var(--space-md);
  border-radius: var(--r-pill);
  background: var(--gradient-dark);
  color: white;
  font-weight: 800;
  font-size: var(--text-md);
  cursor: pointer;
  border: none;
  transition: all var(--t);
  position: relative;
  overflow: hidden;
}

.contacto-form button::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.6s var(--ease);
}

.contacto-form button:hover::before {
  left: 100%;
}

.contacto-form button:hover {
  transform: translateY(-2px);
  box-shadow: var(--sh-2);
}

.contacto-whatsapp {
  background: linear-gradient(135deg, #25d366 0%, #128c7e 100%);
  color: white;
  border: none;
  box-shadow: var(--sh-2);
}

.contacto-whatsapp h3,
.contacto-whatsapp p {
  color: white;
}

.contacto-datos {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: var(--space-sm);
}

.contacto-datos li {
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--r-md);
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.18);
  color: white;
  font-weight: 700;
}

.contacto-whatsapp-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-lg);
  border-radius: var(--r-pill);
  background: white;
  color: #128c7e;
  font-weight: 800;
  text-decoration: none;
  box-shadow: var(--sh-2);
  transition: transform var(--t), box-shadow var(--t);
}

.contacto-whatsapp-btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--sh-3);
}

.contacto-note {
  margin: 0;
  color: rgba(255, 255, 255, 0.9);
  font-size: var(--text-sm);
}

/* =========================
   Footer 
   ========================= */
.footer {
  background: linear-gradient(135deg, var(--ink-1), #1e3440);
  color: white;
  padding: var(--space-xl) 0;
  position: relative;
  overflow: hidden;
}

.footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: 
    radial-gradient(circle at 20% 80%, rgba(255, 255, 255, 0.05) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(255, 255, 255, 0.03) 0%, transparent 50%);
}

.footer-contenido {
  width: var(--w);
  margin: auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-md);
  text-align: center;
  position: relative;
  z-index: 1;
}


.footer-logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.footer-logo img {
  height: px !important; 
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.2));
  opacity: 0.9;
}

.footer-logo h3 {
  margin: 0;
  font-family: 'Times New Roman', serif;
  font-weight: 200;
  font-size: var(--text-2xl);
  color: white;
  letter-spacing: -0.5px;
}

.footer-links {
  display: flex;
  gap: var(--space-lg);
  flex-wrap: wrap;
  justify-content: center;
  margin-top: var(--space-md);
}

.footer-links a {
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--r-sm);
  transition: all var(--t-fast);
  position: relative;
}

.footer-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: white;
  transition: all var(--t);
  transform: translateX(-50%);
}

.footer-links a:hover::after {
  width: 80%;
}

.footer-links a:hover {
  background: rgba(255, 255, 255, 0.1);
}

.footer-copyright {
  margin-top: var(--space-md);
  font-size: var(--text-sm);
  opacity: 0.8;
}

/* =========================
   Scroll Progress 
   ========================= */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: var(--gradient-primary);
  z-index: 101;
  transition: width 0.1s linear;
}

/* =========================
   carga
   ========================= */
.page-load {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--gradient-primary);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  animation: fadeOut 0.8s var(--ease) 0.5s forwards;
}

@keyframes fadeOut {
  to {
    opacity: 0;
    visibility: hidden;
  }
}

/* =========================
   Reduced 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;
  }
  
  .paso {
    opacity: 1;
    transform: none !important;
  }
}

/* =========================
   Responsive
   ========================= */
@media (max-width: 768px) {
  :root {
    --w: min(100%, calc(100% - 24px));
    --header-h: 72px;
  }
  
  body.nav-open {
    overflow: hidden;
  }
  
  .header {
    padding: var(--space-sm) var(--space-md);
    gap: var(--space-md);
  }

  .nav-toggle {
    display: inline-flex;
    align-self: flex-end;
    margin-left: auto;
  }

  .serena-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    width: 100%;
    padding: var(--space-sm) var(--space-md) var(--space-md);
    background: linear-gradient(180deg, rgba(153, 208, 244, 0.98), rgba(109, 156, 185, 0.96));
    box-shadow: var(--sh-2);
    transform: translateY(-120%);
    opacity: 0;
    pointer-events: none;
    transition: transform var(--t), opacity var(--t);
    z-index: 99;
    backdrop-filter: blur(12px);
  }

  .nav-open .serena-nav {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .serena-nav ul {
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-xs);
    background: transparent;
    border: none;
    box-shadow: none;
    padding: 0;
  }
  
  .serena-nav a {
    text-align: center;
    width: 100%;
  }

  .hero {
    padding: var(--space-xl) 0;
  }
  
  .hero h2 {
    font-size: var(--text-3xl);
  }

  .que-es-serena {
    margin: var(--space-xl) auto;
  }

  .countdown {
    margin: var(--space-md) auto var(--space-lg);
  }
  
  .countdown-inner {
    grid-template-columns: 1fr;
    padding: var(--space-md);
  }
  
  .countdown-grid {
    grid-template-columns: repeat(4, minmax(64px, 1fr));
    gap: var(--space-xs);
  }
  
  .pasos {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }
  
  .beneficios-grid {
    grid-template-columns: 1fr;
  }
  
  .problema-boxes {
    grid-template-columns: 1fr;
  }

  .por-que-serena {
    width: min(100%, calc(100% - 24px));
    padding: var(--space-lg) var(--space-md);
    margin: var(--space-xl) auto;
  }
  
  .por-que-serena h2 {
    font-size: var(--text-3xl);
  }
  
  .footer-logo img {
    height: 36px !important;
  }
  
  .footer-logo h3 {
    font-size: var(--text-xl);
  }
}

@media (max-width: 480px) {
  :root {
    --header-h: 68px;
  }

  .countdown-inner {
    padding: var(--space-sm) var(--space-md);
  }

  .countdown-grid {
    grid-template-columns: repeat(4, minmax(60px, 1fr));
    gap: 6px;
  }

  .count-item span {
    font-size: 1.6rem;
  }
  
  .header-serena h1 {
    font-size: var(--text-2xl);
  }
  
  .hero .cta {
    width: 100%;
    justify-content: center;
  }
  
  .contacto-form {
    padding: 0;
  }
  
  .footer-logo {
    flex-direction: column;
    gap: var(--space-xs);
  }
}