:root { color-scheme: light; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif; }
* { box-sizing: border-box; }
html, body { width: 100%; height: 100%; margin: 0; overflow: hidden; background: #e8edf3; color: #162033; }
body { display: grid; grid-template-rows: auto minmax(0, 1fr); }
.source-preview-toolbar { position: relative; z-index: 2; display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: .85rem; min-height: 64px; padding: .65rem .85rem; border-bottom: 1px solid #d8e0ea; background: rgba(255,255,255,.97); box-shadow: 0 2px 10px rgba(15,23,42,.08); }
.source-preview-title { min-width: 0; }
.source-preview-title strong, .source-preview-title span { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.source-preview-title strong { font-size: .95rem; line-height: 1.35; }
.source-preview-title span { margin-top: .12rem; color: #64748b; font-size: .75rem; }
.source-preview-actions { display: flex; align-items: center; gap: .5rem; }
.source-preview-button { display: inline-flex; align-items: center; justify-content: center; gap: .35rem; min-height: 38px; padding: .45rem .75rem; border: 1px solid #cbd5e1; border-radius: .55rem; background: #fff; color: #334155; font: inherit; font-size: .84rem; font-weight: 650; line-height: 1; text-decoration: none; white-space: nowrap; cursor: pointer; }
.source-preview-button:hover, .source-preview-button:focus-visible { border-color: #8a9cb5; background: #f8fafc; outline: none; }
.source-preview-button:focus-visible { box-shadow: 0 0 0 3px rgba(37,99,235,.2); }
.source-preview-button--primary { border-color: #2563eb; background: #2563eb; color: #fff; }
.source-preview-button--primary:hover, .source-preview-button--primary:focus-visible { border-color: #1d4ed8; background: #1d4ed8; }
.source-preview-content { position: relative; min-width: 0; min-height: 0; padding: .65rem; }
.source-preview-content iframe { display: block; width: 100%; height: 100%; border: 0; border-radius: .45rem; background: #fff; box-shadow: 0 1px 5px rgba(15,23,42,.12); }
.source-preview-fallback { position: absolute; inset: 1.5rem; margin: 0; padding: 1rem; border-radius: .5rem; background: #fff; color: #475569; }
@media (max-width: 640px) {
  .source-preview-toolbar { grid-template-columns: auto minmax(0, 1fr); gap: .55rem; padding: .55rem; }
  .source-preview-actions { grid-column: 1 / -1; display: grid; grid-template-columns: 1fr 1fr; }
  .source-preview-actions .source-preview-button { width: 100%; }
  .source-preview-content { padding: .4rem; }
}