* {
  background: #151515;
}
.centrado {
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.spinner {
  border: 6px solid #9F0202;
  width: 60px;
  height: 60px;
  border-radius: 70%;
  border-left-color: #2E2E2E;
  
  animation: spinnerA 0.7s linear infinite;
  
}
@keyframes spinnerA {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

@media (max-width: 768px) {
  * {
  background: #151515;
}
.centrado {
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.spinner {
  border: 6px solid #9F0202;
  width: 80px;
  height: 80px;
  border-radius: 70%;
  border-left-color: #2E2E2E;
  
  animation: spinnerA 0.7s linear infinite;
  
}
@keyframes spinnerA {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}
}