.gradient-blue { 
  background: linear-gradient(135deg, #1e3c72, #2a5298); 
}
.gradient-purple {
  background: linear-gradient(135deg, #8e2de2, #4a00e0);
}

.gradient-green {
  background: linear-gradient(135deg, #11998e, #38ef7d);
}

.gradient-orange {
  background: linear-gradient(135deg, #f12711, #f5af19);
}

.gradient-pink {
  background: linear-gradient(135deg, #ff6a88, #ff99ac);
}

.gradient-gray {
  background: linear-gradient(135deg, #3e5151, #decba4);
}

.gradient-gold {
  background: linear-gradient(135deg, #f7971e, #ffd200);
}

.gradient-teal {
  background: linear-gradient(135deg, #43cea2, #185a9d);
}

.gradient-rainbow {
  background: linear-gradient(90deg, #ff6a00, #ee0979, #00c6ff, #0072ff);
  background-size: 400% 400%;
  animation: rainbowShift 10s ease infinite;
}

.gradient-night {
  background: linear-gradient(135deg, #232526, #414345);
}

@keyframes rainbowShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}