body.ui-style-2 {
  --primary-color: #3498db;
  --secondary-color: #2c3e50;
  --accent-color: #e74c3c;
  --light-bg: #ecf0f1;
}

.video-card {
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.video-card:hover {
  border-color: var(--primary-color);
}

a {
  transition: color 0.2s ease;
}

.back-to-top {
  position: fixed;
  bottom: 40px;
  right: 40px;
  width: 50px;
  height: 50px;
  background: var(--primary-color);
  color: white;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s;
  font-size: 20px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background: var(--secondary-color);
  transform: translateY(-4px);
}

@media (max-width: 768px) {
  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 44px;
    height: 44px;
    font-size: 18px;
  }
}