.rtbp-shell {
  box-sizing: border-box;
  width: 100%;
  max-width: 1800px;
  margin: 0 auto;
  background: #fff;
}
.rtbp-shell *, .rtbp-shell *::before, .rtbp-shell *::after { box-sizing: border-box; }
.rtbp-frame {
  display: block;
  width: 100%;
  height: var(--rtbp-frame-height, 980px);
  border: 1px solid #a9bdc5;
  border-radius: 10px;
  background: #fff;
}
.rtbp-footer {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 11px 4px;
  color: #3a5867;
  font: 14px/1.45 system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}
.rtbp-footer a { color: #bd0d3e; text-decoration: underline; white-space: nowrap; }
.rtbp-footer a:focus-visible { outline: 2px solid #bd0d3e; outline-offset: 3px; }
@media (max-width: 780px) {
  .rtbp-frame { height: max(var(--rtbp-frame-height, 980px), 1300px); }
  .rtbp-footer { flex-direction: column; }
}
@media print {
  .rtbp-shell { display: none !important; }
}