:root {
  --viewer-bg: #f6f8fb;
  --viewer-card: #ffffff;
  --viewer-border: rgba(15, 23, 42, 0.1);
  --viewer-accent: #2563eb;
  --viewer-success: #16a34a;
  --viewer-text: #0f172a;
}

.viewer-shell {
  display: grid;
  grid-template-columns: minmax(260px, 320px) minmax(0, 1fr);
  min-height: 100vh;
  background: var(--viewer-bg);
  color: var(--viewer-text);
}

.sample-sidebar {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 16px;
  border-right: 1px solid var(--viewer-border);
}

.sample-card {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr) auto;
  gap: 12px;
  align-items: center;
  padding: 12px;
  border: 1px solid var(--viewer-border);
  border-radius: 8px;
  background: var(--viewer-card);
  transition: border-color 160ms ease, transform 160ms ease;
}

.sample-card:hover {
  border-color: color-mix(in srgb, var(--viewer-accent), white 55%);
  transform: translateY(-1px);
}

.sample-card[aria-current='true'] {
  border-color: var(--viewer-success);
  box-shadow: 0 10px 28px rgba(22, 163, 74, 0.12);
}

.viewer-panel {
  min-width: 0;
  overflow: hidden;
  border: 1px solid var(--viewer-border);
  background: #e5e7eb;
}

@media (max-width: 780px) {
  .viewer-shell {
    grid-template-columns: 1fr;
  }

  .sample-sidebar {
    border-right: 0;
    border-bottom: 1px solid var(--viewer-border);
  }
}