body {
  background: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}
.glass-effect {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.15);
}
.player-controls {
  background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
}
.track-item {
  transition: all 0.3s ease;
}
.track-item:hover {
  background: rgba(255, 255, 255, 0.08);
  transform: translateX(5px);
}
.upload-area {
  border: 2px dashed rgba(255, 255, 255, 0.3);
  transition: all 0.3s ease;
}
.upload-area:hover {
  border-color: rgba(255, 255, 255, 0.6);
  background: rgba(255, 255, 255, 0.05);
}
.progress-fill {
  background: linear-gradient(270deg, #00d4ff, #7a00ff, #00d4ff);
  background-size: 400% 400%;
  animation: progressGlow 6s ease infinite;
}
@keyframes progressGlow {
  0% {
    background-position: 0% 50%;
  }
  100% {
    background-position: 100% 50%;
  }
}
.btn-primary {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  transition: all 0.3s ease;
}
.btn-primary:hover {
  transform: scale(1.05);
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}
.music-wave {
  display: inline-block;
  width: 20px;
  height: 20px;
  margin-right: 10px;
}
.music-wave span {
  display: inline-block;
  width: 3px;
  height: 100%;
  background: #00d4ff;
  margin-right: 2px;
  animation: wave 1s ease-in-out infinite;
}
.music-wave span:nth-child(2) {
  animation-delay: 0.1s;
}
.music-wave span:nth-child(3) {
  animation-delay: 0.2s;
}
.music-wave span:nth-child(4) {
  animation-delay: 0.3s;
}
@keyframes wave {
  0%, 100% {
    transform: scaleY(0.4);
  }
  50% {
    transform: scaleY(1);
  }
}