/* ==========================================
   VARIABLES Y COLORES OFICIALES DE LA NASA
   ========================================== */
:root {
  --nasa-blue: #0B3D91;      /* Azul principal */
  --nasa-red: #FC3D21;       /* Rojo de acento */
  --nasa-dark: #0B0E14;      /* Fondo oscuro espacial */
  --nasa-card-bg: #161B22;  /* Fondo de tarjetas */
  --nasa-white: #FFFFFF;     /* Texto y elementos claros */
  --nasa-text-gray: #A3B1C2; /* Texto secundario */
  --font-main: 'Titillium Web', sans-serif;
}

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

body {
  font-family: var(--font-main);
  background-color: var(--nasa-dark);
  color: var(--nasa-white);
  line-height: 1.6;
}

/* ==========================================
   NAVEGACIÓN / HEADER
   ========================================== */
.navbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 3rem;
  background-color: rgba(11, 14, 20, 0.95);
  border-bottom: 2px solid var(--nasa-blue);
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(8px);
}

.logo-container {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.logo {
  height: 45px;
  width: auto;
}

.agency-title {
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--nasa-text-gray);
  max-width: 250px;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 2rem;
}

.nav-links a {
  color: var(--nasa-white);
  text-decoration: none;
  font-weight: 600;
  text-transform: uppercase;
  font-size: 0.9rem;
  letter-spacing: 1px;
  transition: color 0.3s ease;
}

.nav-links a:hover {
  color: var(--nasa-red);
}

/* ==========================================
   SECCIÓN HERO
   ========================================== */
.hero {
  position: relative;
  height: 85vh;
  background: url('https://images.unsplash.com/photo-1446776811953-b23d57bd21aa?auto=format&fit=crop&w=1920&q=80') center/cover no-repeat;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  padding: 0 5%;
}

.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, rgba(11,14,20,0.9) 0%, rgba(11,14,20,0.4) 60%, rgba(11,14,20,0.1) 100%);
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 650px;
}

.badge {
  background-color: var(--nasa-red);
  color: var(--nasa-white);
  padding: 0.3rem 0.8rem;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  border-radius: 2px;
}

.hero-content h1 {
  font-size: 3.5rem;
  line-height: 1.1;
  margin: 1rem 0;
  font-weight: 700;
  text-transform: uppercase;
}

.hero-content p {
  font-size: 1.2rem;
  color: var(--nasa-text-gray);
  margin-bottom: 2rem;
}

/* Botones */
.btn {
  display: inline-block;
  padding: 0.8rem 1.8rem;
  font-family: var(--font-main);
  font-weight: 700;
  text-transform: uppercase;
  text-decoration: none;
  letter-spacing: 1px;
  border-radius: 3px;
  transition: all 0.3s ease;
}

.btn-primary {
  background-color: var(--nasa-blue);
  color: var(--nasa-white);
  border: 2px solid var(--nasa-blue);
}

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

.btn-secondary {
  background-color: transparent;
  color: var(--nasa-white);
  border: 1px solid var(--nasa-blue);
  font-size: 0.85rem;
  padding: 0.5rem 1rem;
}

.btn-secondary:hover {
  background-color: var(--nasa-blue);
}

/* ==========================================
   SECCIÓN DE CONTENIDO / TARJETAS
   ========================================== */
.content-section {
  padding: 5rem 5%;
  max-width: 1300px;
  margin: 0 auto;
}

.section-title {
  font-size: 2.2rem;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  margin-bottom: 2.5rem;
  border-left: 4px solid var(--nasa-red);
  padding-left: 1rem;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.card {
  background-color: var(--nasa-card-bg);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 4px;
  overflow: hidden;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 20px rgba(11, 61, 145, 0.3);
  border-color: var(--nasa-blue);
}

.card-img {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.card-body {
  padding: 1.5rem;
}

.card-body h3 {
  font-size: 1.3rem;
  margin-bottom: 0.8rem;
  color: var(--nasa-white);
}

.card-body p {
  color: var(--nasa-text-gray);
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
}

/* ==========================================
   PIE DE PÁGINA
   ========================================== */
footer {
  background-color: #05070a;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 2.5rem 5%;
  text-align: center;
  color: var(--nasa-text-gray);
  font-size: 0.9rem;
}

footer p {
  margin: 0.3rem 0;
}

/* Adaptabilidad a pantallas pequeñas */
@media (max-width: 768px) {
  .navbar {
    flex-direction: column;
    gap: 1rem;
    padding: 1rem;
  }

  .agency-title {
    display: none;
  }

  .hero-content h1 {
    font-size: 2.4rem;
  }
}