.app {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100dvh;
}

.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-bg-dark);
  color: var(--color-text-inverse);
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--spacing-lg);
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.15);
}

.header-title {
  font-family: var(--font-display);
  font-size: var(--font-size-lg);
  font-weight: 900;
  letter-spacing: 0.03em;
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.header-btn {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  color: var(--color-text-inverse);
  opacity: 0.7;
  transition:
    opacity var(--transition-fast),
    background var(--transition-fast);
  font-size: 1.15rem;
}

.header-btn:hover {
  opacity: 1;
  background: rgba(255, 255, 255, 0.1);
}

.header-btn.active {
  opacity: 1;
  color: var(--color-warning);
}

.category-tabs {
  position: sticky;
  top: var(--header-height);
  z-index: 90;
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-card-border);
  display: flex;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
  padding: 0 var(--spacing-md);
  gap: var(--spacing-xs);
}

.category-tabs::-webkit-scrollbar {
  display: none;
}

.category-tab {
  flex-shrink: 0;
  padding: var(--spacing-sm) var(--spacing-md);
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-text-secondary);
  border-bottom: 2px solid transparent;
  transition:
    color var(--transition-fast),
    border-color var(--transition-fast);
  white-space: nowrap;
  height: var(--tab-height);
  display: flex;
  align-items: center;
  gap: 6px;
}

.category-tab svg {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
}

.header-icon {
  display: flex;
  align-items: center;
}

.header-icon svg {
  opacity: 0.85;
}

.category-tab:hover {
  color: var(--color-text);
}

.category-tab.active {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
  font-weight: 700;
}

.main-content {
  flex: 1;
  padding: var(--spacing-lg);
  max-width: 720px;
  margin: 0 auto;
  width: 100%;
}

.footer {
  text-align: center;
  padding: var(--spacing-xl) var(--spacing-lg);
  font-size: var(--font-size-xs);
  color: var(--color-text-secondary);
  letter-spacing: 0.05em;
}

.footer-logo {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: var(--font-size-sm);
  color: var(--color-text);
  margin-bottom: var(--spacing-xs);
}

@media (max-width: 480px) {
  .main-content {
    padding: var(--spacing-md);
  }
}