html {
  height: 100%;
}

body {
  margin: 0;
  padding: 0;
  font-family: sans-serif;
  background: linear-gradient(#141e30, #243b55);
}

.login-box {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 400px;
  padding: 40px;
  transform: translate(-50%, -50%);
  background: rgba(0, 0, 0, 0.5);
  box-sizing: border-box;
  box-shadow: 0 15px 25px rgba(0, 0, 0, 0.6);
  border-radius: 10px;
}

.login-box h2 {
  margin: 0 0 30px;
  padding: 0;
  color: #fff;
  text-align: center;
}

.login-box .user-box {
  position: relative;
}

.login-box .user-box input {
  width: 100%;
  padding: 10px 0;
  font-size: 16px;
  color: #fff;
  margin-bottom: 30px;
  border: none;
  border-bottom: 1px solid #fff;
  outline: none;
  background: transparent;
}

.login-box .user-box label {
  position: absolute;
  top: 0;
  left: 0;
  padding: 10px 0;
  font-size: 16px;
  color: #fff;
  pointer-events: none;
  transition: 0.5s;
}

.login-box .user-box input:focus ~ label,
.login-box .user-box input:valid ~ label {
  top: -20px;
  left: 0;
  color: #03e9f4;
  font-size: 12px;
}

.Boton {
  display: flex;
  justify-content: space-between;
  margin-top: 20px;
}

.Boton button {
  flex: 1;
  border: 0;
  background: none;
  border-radius: 8px;
  color: #fff;
  font-size: 18px;
  padding: 10px;
  cursor: pointer;
  transition: 0.3s;
  position: relative;
  overflow: hidden;
}

.Boton button span {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 16px 24px;
  border-radius: 6px;
  transition: 0.3s;
  position: relative;
}

.Boton button:before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(-45deg, #03e9f4, #391056, #00DDFF);
  z-index: -1;
  opacity: 0;
  transition: opacity 0.3s;
}

.Boton button:hover:before {
  opacity: 1;
}