.mainframe-diagram { margin: 2rem 0; }
.mainframe-diagram img { display: block; width: 100%; height: auto; }
.mainframe-diagram figcaption { margin-top: .75rem; color: var(--text-soft); font-size: .875rem; line-height: 1.5; }
.mainframe-diagram a:focus-visible { outline: 2px solid var(--blue); outline-offset: 4px; }