.walkthrough-page header, .walkthrough-page main, .walkthrough-page footer {
  width: min(1280px, calc(100% - 40px));
}
.walkthrough-page h1 { max-width: 24ch; }
.walkthrough-page #first-project { padding-top: 40px; scroll-margin-top: 24px; }
.walkthrough-page .walkthrough-title {
  max-width: 24ch; font-size: clamp(32px, 5vw, 60px); line-height: 1.08;
  letter-spacing: -.04em; margin: 20px 0 24px;
}
.walkthrough-meta { display: flex; flex-wrap: wrap; gap: 8px 20px; margin: 20px 0; }
.walkthrough-meta span { font: 500 13px ui-monospace, monospace; color: var(--green); }
.walkthrough-player { margin: 30px 0 0; }
.walkthrough-player video {
  display: block; width: 100%; height: auto; aspect-ratio: 16 / 9;
  background: #000; border: 1px solid var(--line); border-radius: 12px;
}
.walkthrough-page :focus-visible { outline: 2px solid var(--green); outline-offset: 4px; }
.walkthrough-page #playback-status { min-height: 28px; font-size: 14px; margin: 8px 0; }
.walkthrough-page .chapter-heading { font-size: 22px; margin: 28px 0 12px; }
.walkthrough-page .chapter-help { font-size: 14px; margin: 0 0 16px; }
.walkthrough-chapters { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8px; }
.walkthrough-chapters a {
  display: flex; align-items: center; gap: 12px; min-height: 56px; padding: 12px 14px;
  color: var(--ink); background: #131914; border: 1px solid var(--line);
  border-radius: 8px; font-size: 14px; line-height: 1.4; text-decoration: none;
}
.walkthrough-chapters time { flex: 0 0 auto; color: var(--green); font: 13px ui-monospace, monospace; }
.walkthrough-chapters a:hover, .walkthrough-chapters a[aria-current="true"] {
  border-color: var(--green); background: #19291f;
}
.walkthrough-transcript { margin: 40px 0; border-top: 1px solid var(--line); padding-top: 20px; }
.walkthrough-transcript summary { cursor: pointer; min-height: 48px; padding: 10px 0; font-size: 23px; }
.walkthrough-transcript section { max-width: 76ch; }
.walkthrough-transcript h3 { margin: 32px 0 10px; }
.walkthrough-transcript p { margin: 12px 0; }
.walkthrough-notes { max-width: 80ch; }
.walkthrough-page .downloads { display: flex; flex-wrap: wrap; gap: 8px 24px; }
.walkthrough-page .downloads a { display: inline-flex; align-items: center; min-height: 44px; }
@media (max-width: 800px) {
  .walkthrough-chapters { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 520px) {
  .walkthrough-page header, .walkthrough-page main, .walkthrough-page footer { width: calc(100% - 32px); }
  .walkthrough-chapters { grid-template-columns: 1fr; }
  .walkthrough-page .lede { font-size: 18px; }
  .walkthrough-player video { border-radius: 6px; }
  .walkthrough-meta { gap: 10px 16px; }
}