body {
  background: linear-gradient(135deg, #232526 0%, #414345 100%);
  min-height: 100vh;
  font-family: 'Poppins', 'Segoe UI', Arial, sans-serif;
  color: #e9ecef;
  display: flex;
  flex-direction: column;
  position: relative;
  z-index: 1;
  overflow-x: hidden;
}

body::before {
  content: '';
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  z-index: 0;
  pointer-events: none;
  opacity: 0.18;
  background: repeating-linear-gradient(120deg, #fff2 0 2px, transparent 2px 80px),
              repeating-linear-gradient(60deg, #fff1 0 1.5px, transparent 1.5px 60px);
  animation: wavesMove 18s linear infinite;
}

@keyframes wavesMove {
  0% { background-position: 0 0, 0 0; }
  100% { background-position: 120px 60px, -80px 40px; }
}

main.container {
  flex: 1 0 auto;
}

.navbar {
  padding-top: 0.25rem !important;
  padding-bottom: 0.25rem !important;
  min-height: 48px;
  position: relative;
  z-index: 1055 !important;
  background: linear-gradient(90deg, rgba(35,39,43,0.85) 60%, rgba(42,45,52,0.85) 100%);
  backdrop-filter: blur(8px);
  box-shadow: 0 4px 24px 0 rgba(0,123,255,0.10), 0 1.5px 0 0 #00ffae44 inset;
  border-radius: 0 0 18px 18px;
  transition: box-shadow 0.4s cubic-bezier(.4,2,.6,1);
  animation: navbarShadow 2.5s ease-in-out infinite alternate;
}

@keyframes navbarShadow {
  0% { box-shadow: 0 4px 24px 0 rgba(0,123,255,0.10), 0 1.5px 0 0 #00ffae44 inset; }
  100% { box-shadow: 0 8px 32px 0 rgba(0,123,255,0.18), 0 2.5px 0 0 #00ffae88 inset; }
}

.navbar-brand {
  padding-top: 0;
  padding-bottom: 0;
  font-size: 2rem;
  letter-spacing: 2px;
  filter: drop-shadow(0 2px 6px #00ffae44);
  transition: filter 0.3s;
}

.navbar .navbar-brand:hover {
  filter: drop-shadow(0 4px 12px #00ffae88);
}

.card {
  border-radius: 1.2rem;
  border: none;
  background: rgba(120,130,140,0.82) !important;
  box-shadow: 0 4px 32px 0 #0002;
}

.card-title {
  font-weight: 700;
  letter-spacing: 1px;
  color: #fff;
  text-shadow: 0 2px 12px #00ffae22, 0 1px 0 #222a;
}

.card-title i {
  color: #00ffae;
}

#startTest {
  transition: transform 0.2s;
}
#startTest:hover {
  transform: scale(1.08);
  box-shadow: 0 0 20px #00ffae;
}

footer {
  background: linear-gradient(90deg, rgba(35,39,43,0.85) 60%, rgba(42,45,52,0.85) 100%);
  backdrop-filter: blur(8px);
  box-shadow: 0 -4px 24px 0 rgba(0,123,255,0.10);
  flex-shrink: 0;
  position: relative;
  z-index: 2;
  border-radius: 18px 18px 0 0;
  border-top: 1.5px solid #00ffae44;
}

.list-group-item {
  border: none;
  font-size: 1.1rem;
}

.list-group-item b {
  color: #00ffae;
  font-weight: 600;
}

.list-group-item span {
  color: #fff;
  font-weight: 500;
  letter-spacing: 0.2px;
}

.lead, .mb-0.text-secondary {
  color: #bfc9d1 !important;
}

/* Animaciones personalizadas */
@keyframes flash {
  0% { box-shadow: 0 0 0 0 #00ffae; }
  70% { box-shadow: 0 0 20px 10px #00ffae33; }
  100% { box-shadow: 0 0 0 0 #00ffae; }
}

#startTest:active {
  animation: flash 0.5s;
}

/* Responsive: tarjeta info ocupa 100% en móviles */
@media (max-width: 767.98px) {
  .col-md-6 {
    flex: 0 0 100%;
    max-width: 100%;
  }
  .card {
    border-radius: 0.7rem;
  }
  main.container {
    padding-left: 0.2rem;
    padding-right: 0.2rem;
  }
  .navbar {
    padding-left: 0 !important;
    padding-right: 0 !important;
  }
  .container-fluid {
    padding-left: 0.5rem !important;
    padding-right: 0.5rem !important;
  }
}

html, body {
  max-width: 100vw;
  overflow-x: hidden;
}

/* Fondo animado con partículas sutiles solo en escritorio */
body::before {
  content: '';
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  z-index: 0;
  pointer-events: none;
  background: repeating-radial-gradient(circle at 20% 30%, rgba(255,255,255,0.06) 0, rgba(255,255,255,0.06) 2px, transparent 3px, transparent 100px),
              repeating-radial-gradient(circle at 70% 60%, rgba(200,200,200,0.08) 0, rgba(200,200,200,0.08) 1.5px, transparent 2.5px, transparent 120px),
              repeating-radial-gradient(circle at 50% 80%, rgba(180,180,180,0.08) 0, rgba(180,180,180,0.08) 2px, transparent 3px, transparent 90px);
  animation: moveParticles 18s linear infinite;
}

@keyframes moveParticles {
  0% { background-position: 0 0, 0 0, 0 0; }
  100% { background-position: 60px 40px, -40px 60px, 30px -30px; }
}

main, .navbar, footer {
  position: relative;
  z-index: 2;
}

/* Navbar inteligente: animación de aparición/desaparición */
.navbar.smart-hide {
  transform: translateY(-100%);
  transition: transform 0.4s cubic-bezier(.4,2,.6,1);
}
.navbar.smart-show {
  transform: translateY(0);
  transition: transform 0.4s cubic-bezier(.4,2,.6,1);
}

.dropdown-menu {
  z-index: 2000 !important;
}

.table-responsive {
  overflow-x: auto;
  width: 100%;
}
.table-sm th, .table-sm td {
  word-break: break-all;
  white-space: pre-line;
  max-width: 320px;
}
@media (max-width: 600px) {
  .table-sm th, .table-sm td {
    max-width: 120px;
    font-size: 0.95em;
  }
}