.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.5rem 1.5rem;
  background: linear-gradient(135deg, rgba(135, 206, 235, 0.05), rgba(173, 216, 230, 0.05));
  border-bottom: 2px solid #87CEEB;
  box-shadow: 0 4px 12px rgba(135, 206, 235, 0.15);
  backdrop-filter: blur(20px);
  transition: top 0.2s, transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.app-header-hidden {
  transition: top 0.2s, transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.header-left {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.app-title {
  font-size: 1.5rem;
  font-weight: bold;
  color: #87CEEB;
  letter-spacing: 0.02em;
  text-shadow: 0 0 8px rgba(135, 206, 235, 0.3);
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 1rem;
}


.header-button {
  background: transparent;
  border: none;
  font-size: 1.2rem;
  cursor: pointer;
  padding: 0.4rem;
  min-width: 36px;
  height: 36px;
  border-radius: 50%;
  color: #87CEEB;
  transition: all 0.3s ease;
}

.header-button:hover {
  background: rgba(135, 206, 235, 0.15);
  color: #87CEEB;
  box-shadow: 0 4px 12px rgba(135, 206, 235, 0.25);
  transform: translateY(-1px);
}

.header-button.active {
  background: linear-gradient(135deg, #87CEEB, #b983ff);
  color: #fff;
  box-shadow: 0 0 16px rgba(185, 131, 255, 0.4);
}

.header-button.active:hover {
  background: linear-gradient(135deg, #b983ff, #87CEEB);
  box-shadow: 0 0 20px rgba(185, 131, 255, 0.5);
}

.header-button.danger {
  color: #FFB6C1;
}

.header-button.danger:hover {
  background: rgba(255, 182, 193, 0.15);
  color: #FFB6C1;
  box-shadow: 0 4px 12px rgba(255, 182, 193, 0.25);
}