.oferta-img{
  width:100%;
  height:300px;        
  object-fit:cover;
  display:block;
  margin-inline:auto;  
}

@media (min-width:768px){  
  .oferta-img{ height:240px; }
}
@media (min-width:992px){  
  .oferta-img{ width:90%; height:450px; } 
}

@media (max-width: 991px) { 
    .navbar-collapse {
      background-color: white !important;
      padding: 1rem; 
    }

    .navbar-collapse .nav-link {
      color: #000 !important; 
    }
}

.img-cuadrada {
  width: 500px;     
  height: 500px;    
  object-fit: cover; 
}

:root {        
  --bg-color: #ffffff;
  --text-color: #000000;
}

body.dark-theme {
  --bg-color: #121212;
  --text-color: #e0e0e0;
}

body {
  background-color: var(--bg-color);
  color: var(--text-color);
  font-family: Arial, sans-serif;
  transition: background-color 0.4s, color 0.4s;
}

button {
  padding: 10px 20px;
  margin: 20px;
  border: none;
  cursor: pointer;
  background-color: var(--text-color);
  color: var(--bg-color);
  border-radius: 8px;
  transition: background-color 0.3s, color 0.3s;
}

.btn-fab {
  position: fixed;
  left: max(1rem, env(safe-area-inset-left));
  bottom: max(1rem, env(safe-area-inset-bottom));
  z-index: 1050;
  width: 48px;
  height: 48px;
  padding: 0;                  
  margin: 0;                    
  border-radius: 9999px;
  display: grid;
  place-items: center;
  font-size: 1.25rem;
  line-height: 1;
  background-color: color-mix(in srgb, var(--bg-color) 85%, transparent);
  color: var(--text-color);
  border: 1px solid color-mix(in srgb, var(--text-color) 25%, transparent);
  box-shadow: 0 6px 18px rgba(0,0,0,.25);
  backdrop-filter: blur(6px);
  transition: transform .15s ease, background-color .15s ease, color .15s ease;
}

.btn-fab:hover {
  transform: scale(1.06);
  background-color: color-mix(in srgb, var(--bg-color) 100%, transparent);
}

body.dark-theme .btn-fab {
  box-shadow: 0 6px 18px rgba(0,0,0,.45);
}

.navbar {
  min-height: 70px; 
}

.navbar-brand {
  color: white !important;
  text-align: left;
  margin: 0;
}

.navbar-nav .nav-link {
  color: white !important;
  transition: color 0.2s ease;
}

.navbar-nav .nav-link:hover {
  color: #66fcf1 !important;
}

#open-quiz {
  font-size: 0.9rem;
  border-radius: 8px;
  transition: all 0.3s ease;
}

#open-quiz:hover {
  transform: scale(1.05);
}

.prose {
  max-width: 65ch;        
  line-height: 1.6;
}

.tip {
  padding-block: .25rem;
  border-bottom: 1px solid rgba(255,255,255,.06);
}
.tip:last-of-type {
  border-bottom: none;
}

.ratio-cover {
  width: 100%;
  aspect-ratio: 16 / 9;   
  object-fit: cover;       
  object-position: center;
  display: block;
}

@media (min-width: 992px) {
  .tip {
    margin-bottom: .25rem;
  }
}

@media (min-width: 768px) {
  .prose {
    margin-left: 0;
  }
}

/* modo oscuro para las tarjetas */
.card {
  background-color: #1e1e1e !important; 
  color: #e0e0e0 !important; 
  border: 1px solid #333 !important; 
}

.btn-success {
  background-color: #00ff80 !important; /* verde neón */
  border-color: #00ff80 !important;
  color: #000 !important; /* texto oscuro para contraste */
  font-weight: 500;
  box-shadow: 0 0 12px rgba(0, 255, 128, 0.6); /* brillo neón */
  transition: all 0.2s ease-in-out;
}

.btn-success:hover {
  background-color: #00ffa0 !important; /* un poco más brillante al pasar el mouse */
  border-color: #00ffa0 !important;
  box-shadow: 0 0 18px rgba(0, 255, 160, 0.8);
}

.titulo-neon {
  color: #00ff80 !important;         
  text-shadow: 0 0 10px #00ff80;      
  font-weight: 600;
}