.pdf-shell {
  display: flex;
  flex-direction: column;
  width: 100%;
  height: 100%;
  min-height: 60vh;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.pdf-shell--center {
  align-items: center;
  justify-content: center;
}

.pdf-toolbar {
  position: sticky;
  top: 0;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
  padding: 0.5rem 0.75rem;
}

.pdf-toolbar__group {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.pdf-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 2rem;
  height: 2rem;
  padding: 0 0.6rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  color: var(--text-primary);
  font-size: 1rem;
  line-height: 1;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, transform 0.1s ease;
}

.pdf-btn:not(:disabled):hover {
  background: var(--bg-hover);
  border-color: var(--border-strong);
}

.pdf-btn:not(:disabled):active {
  transform: scale(0.96);
}

.pdf-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.pdf-btn--zoom-label {
  min-width: 3.5rem;
  font-size: 0.8rem;
  font-variant-numeric: tabular-nums;
}

.pdf-btn--download {
  gap: 0.35rem;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--accent-color);
  border-color: var(--accent-color);
}

.pdf-btn--download:not(:disabled):hover {
  background: var(--accent-bg);
}

.pdf-page-info {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  font-size: 0.85rem;
  color: var(--text-secondary);
  padding: 0 0.4rem;
  font-variant-numeric: tabular-nums;
}

.pdf-page-info__current {
  color: var(--text-primary);
  font-weight: 600;
}

.pdf-viewport {
  flex: 1;
  overflow-y: auto;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  padding: 1.5rem;
}

.pdf-page {
  box-shadow: var(--shadow-lg);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: opacity 0.2s ease;
}

.pdf-page--rendering {
  opacity: 0.6;
}

.pdf-page-loading,
.pdf-page-error {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.pdf-page-error {
  color: #b91c1c;
}

.pdf-empty {
  color: var(--text-muted);
  font-size: 0.9rem;
}