/* ==========================================================================
   MATRIZ CROMÁTICA CORPORATIVA (VARIABLES GLOBALES)
   ========================================================================== */
:root {
  /* --- PALETA DE MARCA ESTRICTA --- */
  --brand-primary: #173B48; /* Azul Petróleo Oscuro (Logo) */
  --brand-sec-1: #578D5C;   /* Verde Bosque */
  --brand-sec-2: #B4CD86;   /* Verde Lima Suave */
  --brand-sec-3: #6FBDC2;   /* Cian Claro */
  --brand-sec-4: #4695A1;   /* Cian Medio */
  --brand-sec-5: #B5DDDD;   /* Cian Grisáceo Muy Claro */

  /* --- ASIGNACIÓN ARMONIOSA DE INTERFAZ (UI) --- */
  --color-primary: var(--brand-primary);       
  --color-primary-light: var(--brand-sec-3);   /* Textos destacados, hovers sobre fondos oscuros */
  
  --color-action: var(--brand-sec-4);          /* Botones y bordes interactivos */
  --color-action-hover: var(--brand-sec-3);    
  
  --color-accent: var(--brand-sec-2);          /* Precios, Ofertas (Máximo contraste visual) */
  --color-accent-hover: var(--brand-sec-1);

  /* --- FONDOS (DARK THEME BASADO EN #173B48) --- */
  --color-bg: #060E12;            /* Fondo absoluto, derivado ultra oscuro del logo */
  --color-card: #0B1A22;          /* Fondo de tarjetas, ligeramente más claro */
  --color-card-border: var(--brand-primary);   /* Bordes fusionados con el color principal */

  /* --- TIPOGRAFÍA --- */
  --color-text: #F8FAFC;          
  --color-text-secondary: var(--brand-sec-5);  /* Textos secundarios en armonía con el logo */

  /* --- ALERTAS --- */
  --color-danger: #EF4444;        
  --color-success: var(--brand-sec-1);         
}

/* ==========================================================================
   CONFIGURACIÓN ESTRUCTURAL Y RESETEO
   ========================================================================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  overflow-x: hidden;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  width: 100%;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color 0.3s ease, background-color 0.3s ease;
}

ul { list-style: none; }

/* ==========================================================================
   TIPOGRAFÍA CORPORATIVA Y ALINEACIÓN
   ========================================================================== */
h1, h2, h3 {
  color: var(--color-text);
  font-weight: 700;
  line-height: 1.2;
}

/* Títulos de sección matemáticamente centrados y fluidos */
section h2 {
  text-align: center;
  margin-bottom: 3.5rem;
  font-size: clamp(2rem, 5vw, 2.5rem);
  color: #FFF;
  position: relative;
  letter-spacing: -0.5px;
}

/* Subrayado corporativo dinámico atado al color del logotipo */
section h2::after {
  content: '';
  display: block;
  width: 60px;
  height: 4px;
  background-color: var(--color-action);
  margin: 1.2rem auto 0 auto;
  border-radius: 4px;
  box-shadow: 0 2px 10px rgba(70, 149, 161, 0.4); /* Brillo sutil derivado de #4695A1 */
}

/* ==========================================================================
   CABECERA DE NAVEGACIÓN (HEADER)
   ========================================================================== */
header {
  background-color: rgba(255, 255, 255, 0.95); /* Cabecera luminosa para máximo contraste del logo */
  border-bottom: 2px solid var(--color-action);
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 4px 20px rgba(0,0,0,0.3); /* Sombra para separarlo del cuerpo oscuro */
}

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

.logo {
  display: flex;
  align-items: center;
  transition: opacity 0.3s ease, transform 0.3s ease;
}

.logo:hover {
  opacity: 0.9;
  transform: scale(1.02);
}

.logo img {
  max-height: 55px; /* Altura óptima corporativa */
  width: auto;
  object-fit: contain;
}

nav ul { display: flex; gap: 2.5rem; }
nav a { 
  font-size: 0.9rem; 
  font-weight: 700; 
  color: var(--brand-primary); /* Texto del menú en azul petróleo oscuro para resaltar sobre blanco */
  letter-spacing: 0.5px;
}
nav a:hover, nav a.active { 
  color: var(--color-action); /* Pasa a color Cian al poner el cursor encima */
}

/* ==========================================================================
   SECCIÓN PRINCIPAL (HERO)
   ========================================================================== */
.hero-promo {
  padding: clamp(4rem, 8vw, 7rem) 0;
  background: radial-gradient(circle at top right, var(--color-primary) 0%, var(--color-bg) 100%);
  border-bottom: 1px solid var(--color-card-border);
  position: relative;
}

.hero-content {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4rem;
  flex-wrap: wrap;
}

.hero-text { flex: 1; min-width: 300px; }

.hero-text h1 {
  font-size: clamp(2.8rem, 6vw, 4rem);
  color: #FFF;
  margin-bottom: 1.5rem;
  letter-spacing: -1px;
}

.highlight { color: var(--color-primary-light); }

.hero-details {
  background: rgba(255, 255, 255, 0.03);
  padding: 1.5rem 2rem;
  border-radius: 8px;
  border-left: 4px solid var(--color-accent);
  margin: 2rem 0;
  display: inline-block;
  backdrop-filter: blur(5px);
  box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.price-tag { font-size: clamp(1.2rem, 4vw, 1.5rem); margin-bottom: 0.8rem; }
.price-original { text-decoration: line-through; color: var(--color-text-secondary); font-size: 1.2rem; }
.price-final { color: var(--color-accent); font-weight: 800; font-size: clamp(1.8rem, 5vw, 2.2rem); }

.promo-alert {
  display: inline-block;
  background-color: rgba(239, 68, 68, 0.15);
  color: var(--color-danger);
  border: 1px solid rgba(239, 68, 68, 0.3);
  padding: 0.4rem 1.2rem;
  border-radius: 50px;
  font-size: 0.85rem;
  font-weight: 700;
  margin-top: 0.5rem;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.btn-hero {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background-color: var(--color-action);
  color: white;
  padding: 1rem 2.5rem;
  border-radius: 6px;
  font-weight: 700;
  font-size: 1.1rem;
  margin-top: 1.5rem;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(70, 149, 161, 0.3);
}

.btn-hero:hover { 
  background-color: var(--color-action-hover); 
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(70, 149, 161, 0.5);
}

.btn-hero:hover { 
  background-color: var(--color-primary-hover); 
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(10, 92, 255, 0.3);
}

.hero-image {
  flex: 1;
  min-width: 300px;
  display: flex;
  justify-content: center;
}

.hero-image img {
  width: 100%;
  max-width: 550px;
  height: auto;
  max-height: 420px;
  object-fit: cover;
  border-radius: 12px;
  box-shadow: 0 25px 50px rgba(0,0,0,0.5);
  border: 1px solid var(--color-card-border);
}

/* ==========================================================================
   GRID DE CURSOS (CATÁLOGO Y TARJETAS)
   ========================================================================== */
section { padding: clamp(4rem, 6vw, 6rem) 0; }

.grid-container {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 2.5rem;
  margin-top: 3rem;
}

.card {
  background-color: var(--color-card);
  border: 1px solid var(--color-card-border);
  border-radius: 10px;
  overflow: hidden;
  transition: all 0.4s ease;
  position: relative;
  display: flex;
  flex-direction: column;
}

.card:hover {
  transform: translateY(-8px);
  box-shadow: 0 20px 40px rgba(0,0,0,0.6);
  border-color: var(--color-primary-light);
}

.card-img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  object-position: center;
  border-bottom: 1px solid var(--color-card-border);
  transition: transform 0.5s ease;
}

.card:hover .card-img {
  transform: scale(1.05); /* Zoom sutil al pasar el mouse */
}

.card-content {
  padding: 2rem 1.8rem;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
  text-align: center;
  background: var(--color-card);
  position: relative; /* Para aislar del zoom de la imagen */
  z-index: 2;
}

.card-content h3 {
  font-size: 1.3rem;
  margin-bottom: 1rem;
  color: var(--color-text);
}

.card-content p {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  margin-bottom: 1.5rem;
  flex-grow: 1;
}

.btn-card {
  display: inline-block;
  text-align: center;
  padding: 0.9rem 1.5rem;
  border: 1px solid var(--color-action);
  color: var(--color-action);
  background-color: rgba(70, 149, 161, 0.1); /* Fondo translúcido sutil basado en #4695A1 */
  border-radius: 6px;
  font-weight: 600;
  margin-top: auto;
  transition: all 0.3s ease;
  width: 100%;
}

.btn-card:hover { 
  background-color: var(--color-action); 
  color: var(--color-bg); 
}

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

.coming-soon-overlay {
  position: absolute;
  top: 15px;
  right: 15px;
  background-color: rgba(0, 0, 0, 0.85);
  color: var(--color-accent);
  padding: 0.4rem 1rem;
  font-size: 0.75rem;
  font-weight: 800;
  border-radius: 4px;
  border: 1px solid var(--color-accent);
  box-shadow: 0 4px 15px rgba(0,0,0,0.5);
  z-index: 10;
  letter-spacing: 1px;
}

.card.disabled { opacity: 0.6; }
.card.disabled:hover { transform: none; box-shadow: none; border-color: var(--color-card-border); }
.card.disabled .card-img { filter: grayscale(80%); }
.card.disabled:hover .card-img { transform: none; }
.card.disabled .btn-card { 
  border-color: var(--color-card-border); 
  color: var(--color-text-secondary); 
  background: transparent;
  cursor: not-allowed; 
}

/* ==========================================================================
   FORMULARIO DE VALIDACIÓN
   ========================================================================== */
#validation-section {
  max-width: 800px;
  margin: 2rem auto;
  padding: clamp(2rem, 5vw, 4rem);
  background-color: var(--color-card);
  border-radius: 12px;
  border: 1px solid var(--color-card-border);
  text-align: center;
  box-shadow: 0 15px 40px rgba(0,0,0,0.4);
}

#validation-section p {
  margin-bottom: 2.5rem;
  color: var(--color-text-secondary);
}

#validation-form {
  display: flex;
  gap: 1rem;
  margin-bottom: 2rem;
  justify-content: center;
}

#codigo-input {
  flex-grow: 1;
  max-width: 500px;
  padding: 1.2rem;
  border: 1px solid var(--color-card-border);
  background: var(--color-bg);
  color: var(--color-text);
  border-radius: 6px;
  font-size: 1rem;
  text-align: center;
  letter-spacing: 1px;
  transition: all 0.3s ease;
}

#codigo-input:focus {
  outline: none;
  border-color: var(--color-action);
  box-shadow: 0 0 0 3px rgba(70, 149, 161, 0.2);
}

.btn {
  background-color: var(--color-action);
  color: white;
  border: none;
  padding: 1.2rem 2.5rem;
  border-radius: 6px;
  cursor: pointer;
  font-weight: 700;
  font-size: 1rem;
  transition: all 0.3s ease;
}

.btn:hover { 
  background-color: var(--color-action-hover); 
  transform: translateY(-2px);
  box-shadow: 0 4px 15px rgba(70, 149, 161, 0.3);
}

/* ==========================================================================
   PIE DE PÁGINA (FOOTER)
   ========================================================================== */
footer {
  background-color: #03080A; /* Tono ultra oscuro basado en #173B48 */
  padding: 3rem 0;
  text-align: center;
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  border-top: 1px solid var(--color-card-border);
}

/* ==========================================================================
   ADAPTABILIDAD MÓVIL (MEDIA QUERIES)
   ========================================================================== */
@media (max-width: 850px) {
  .hero-content {
    flex-direction: column;
    text-align: center;
    gap: 2.5rem;
  }
  
  .hero-text { width: 100%; }
  
  .hero-details {
    margin: 2rem auto;
    border-left: none;
    border-top: 4px solid var(--color-accent);
    display: block;
    padding: 1.5rem 1rem;
  }
  
  .btn-hero {
    width: 100%;
    max-width: 350px;
    margin: 1.5rem auto 0 auto;
  }
  
  .grid-container {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  
  #validation-form {
    flex-direction: column;
    align-items: center;
  }
  
  #codigo-input, .btn {
    width: 100%;
    max-width: 100%;
  }
}