@layer views {
  /* ── the chrome's own bits: the logo's line, a course's language, the tab bar ── */
  .sb-logo { display: flex; align-items: baseline; gap: 8px; }
  .sb-logo-sub { font-family: var(--mono); font-size: var(--fs-label); font-weight: 500; letter-spacing: var(--track-label); color: var(--muted); }
  .sb-pct, .sb-level { margin-left: auto; font-family: var(--mono); font-size: var(--fs-label); color: var(--muted); }
  .sb-you-main .sb-level { margin-left: 8px; }
  .avatar.lang, .lang-badge {
    font-family: var(--mono); font-weight: 700; font-size: 11px; letter-spacing: 0; text-transform: lowercase;
    background: color-mix(in oklch, var(--lang) 16%, transparent); color: var(--lang);
  }
  [data-lang="python"] { --lang: var(--lang-python); }
  [data-lang="javascript"] { --lang: var(--lang-javascript); }
  .lang-badge { display: inline-grid; place-items: center; min-width: 30px; height: 22px; padding: 0 7px; border-radius: var(--r-item); }

  .topbar .top-gap { flex: 1; }
  .topbar .top-level { font-family: var(--mono); font-size: var(--fs-label); color: var(--muted); padding: 0 4px; }
  .tabbar .tab {
    position: relative; display: grid; justify-items: center; align-content: center; gap: 3px;
    color: var(--muted); text-decoration: none; font-size: 11px; font-weight: 600;
    & svg { width: 20px; height: 20px; }
    &[aria-current="page"] { color: var(--fg); }
    &[aria-current="page"]::before {
      content: ''; position: absolute; top: 0; width: 28px; height: 2px; border-radius: 2px; background: var(--grad);
    }
    & .sb-count {
      position: absolute; top: 6px; left: calc(50% + 6px); min-width: 16px; height: 16px; padding: 0 4px; border-radius: 8px;
      display: grid; place-items: center; background: var(--due); color: var(--bg); font-size: 10px; font-weight: 700;
    }
  }

  /* ── a bar for how far through ── */
  .bar {
    display: block; height: 6px; border-radius: 3px; background: var(--track); overflow: hidden; flex: 1;
    & i { display: block; height: 100%; border-radius: inherit; background: var(--grad); transition: width var(--t) var(--ease-liquid); }
  }

  /* ── home ── */
  .home { display: grid; gap: 18px; align-content: start; }
  .home > .h-sec { margin-top: 10px; }
  .hero-card {
    position: relative; display: grid; gap: 8px; overflow: hidden; isolation: isolate;
    padding: 22px; border-radius: var(--r-card); border: 1px solid var(--line); background: var(--surface);
    color: var(--fg); text-decoration: none;
    transition: border-color var(--t-fast), transform var(--t-fast) var(--ease-spring);
    &::before {
      content: ''; position: absolute; inset: -40% -20% auto auto; width: 70%; aspect-ratio: 1; z-index: -1;
      background: radial-gradient(circle, var(--glow-a), transparent 65%);
    }
    &::after {
      content: ''; position: absolute; inset: auto auto -50% -10%; width: 60%; aspect-ratio: 1; z-index: -1;
      background: radial-gradient(circle, var(--glow-b), transparent 65%);
    }
    &:is(a):hover { border-color: var(--line-2); }
    &:is(a):active { transform: scale(.99); }
  }
  .hero-top { display: flex; align-items: center; gap: 10px; }
  .hero-title { font-size: clamp(24px, 6vw, 32px); letter-spacing: -0.045em; line-height: 1.08; }
  .hero-sub { color: var(--muted); font-size: var(--fs-body-sm); }
  .hero-foot { display: flex; flex-wrap: wrap; align-items: center; gap: 14px 20px; margin-top: 10px; }
  .hero-prog { display: flex; align-items: center; gap: 10px; flex: 1 1 180px; }
  .hero-card .pill.pri { background: var(--grad); color: #06110c; }

  .review-card {
    display: flex; align-items: center; gap: 14px; padding: 16px 18px; border-radius: var(--r-tile);
    border: 1px solid color-mix(in oklch, var(--due) 40%, var(--line)); background: color-mix(in oklch, var(--due) 7%, var(--surface));
    color: var(--fg); text-decoration: none;
    & > svg { width: 16px; height: 16px; color: var(--muted); flex: none; }
  }
  .review-icon { display: grid; place-items: center; width: 38px; height: 38px; border-radius: 50%; background: color-mix(in oklch, var(--due) 18%, transparent); color: var(--due); flex: none;
    & svg { width: 18px; height: 18px; } }
  .review-text { display: grid; gap: 2px; flex: 1; font-size: var(--fs-body-sm); color: var(--fg-2);
    & b { color: var(--fg); font-size: var(--fs-md); } }

  .course-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 280px), 1fr)); gap: 14px; margin-top: 14px; }
  .course-card {
    display: grid; gap: 8px; align-content: start; padding: 20px; border-radius: var(--r-card);
    border: 1px solid var(--line); background: var(--surface); color: var(--fg); text-decoration: none;
    transition: border-color var(--t-fast), transform var(--t-fast) var(--ease-spring);
    &:hover { border-color: color-mix(in oklch, var(--lang) 45%, var(--line-2)); }
    &:active { transform: scale(.99); }
  }
  .course-top { display: flex; align-items: center; justify-content: space-between; gap: 10px; }
  .course-title { font-size: var(--fs-xl); letter-spacing: -0.035em; }
  .course-blurb { color: var(--fg-2); font-size: var(--fs-body-sm); }
  .course-prog { display: flex; align-items: center; gap: 10px; margin-top: 6px; }

  /* ── a course: its chapters as a path ── */
  .back-link { display: inline-flex; align-items: center; gap: 4px; color: var(--muted); text-decoration: none; font-size: var(--fs-sm); font-weight: 600;
    & svg { width: 14px; height: 14px; } &:hover { color: var(--fg); } }
  .course-hero { display: grid; gap: 12px; justify-items: start; margin: 14px 0 28px; }
  .course-hero .course-prog { width: min(100%, 420px); }
  .course-hero .pill.pri { background: var(--grad); color: #06110c; }
  .done-line { display: inline-flex; align-items: center; gap: 6px; color: var(--success); font-weight: 700; & svg { width: 16px; height: 16px; } }

  .path { display: grid; gap: 26px; }
  .chapter-head { display: grid; grid-template-columns: auto 1fr; gap: 14px; align-items: start; margin-bottom: 10px; }
  .chapter-n {
    display: grid; place-items: center; width: 34px; height: 34px; border-radius: 50%; flex: none;
    border: 1.5px solid var(--line-2); font-family: var(--mono); font-weight: 700; font-size: var(--fs-sm); color: var(--muted);
    & svg { width: 16px; height: 16px; }
  }
  .chapter[data-done="true"] .chapter-n { border-color: transparent; background: color-mix(in oklch, var(--success) 18%, transparent); color: var(--success); }
  .chapter[data-here="true"] .chapter-n { border-color: var(--grad-a); color: var(--fg); }
  .chapter-title { font-size: var(--fs-lg); letter-spacing: -0.03em; }
  .chapter-blurb { color: var(--muted); font-size: var(--fs-body-sm); }
  .stops { list-style: none; display: grid; gap: 2px; margin-left: 16px; padding-left: 30px; border-left: 1.5px solid var(--line); }
  .stop {
    position: relative; display: grid; grid-template-columns: 1fr auto; align-items: center; gap: 4px 12px;
    min-height: 48px; padding: 8px 12px; border-radius: var(--r-tile); color: var(--fg-2); text-decoration: none;
    &:hover { background: var(--surface); color: var(--fg); }
    &[data-state="done"] { color: var(--muted); }
    &[data-state="next"] { background: var(--surface); border: 1px solid var(--line-2); color: var(--fg); font-weight: 700; }
  }
  .stop-dot {
    position: absolute; left: -48px; top: 50%; translate: 0 -50%;
    display: grid; place-items: center; width: 28px; height: 28px; border-radius: 50%;
    background: var(--bg); border: 1.5px solid var(--line-2); color: var(--muted);
    & svg { width: 13px; height: 13px; }
  }
  .stop[data-state="done"] .stop-dot { border-color: transparent; background: color-mix(in oklch, var(--success) 20%, var(--bg)); color: var(--success); }
  .stop[data-state="next"] .stop-dot { border: 0; background: var(--grad); color: #06110c; box-shadow: 0 0 0 5px color-mix(in oklch, var(--grad-a) 18%, transparent); }
  .stop-title { font-size: var(--fs-md); }
  .stop-meta { display: inline-flex; align-items: center; gap: 8px; font-family: var(--mono); font-size: var(--fs-label); color: var(--muted); font-weight: 500; }
  .chip.sm { padding: 1px 8px; font-size: var(--fs-label); font-family: var(--mono); }

  /* ── reviews ── */
  .review-page { display: grid; gap: 16px; align-content: start; }
  .review-head { display: grid; gap: 8px; }
  .review-bar { height: 4px; border-radius: 2px; background: var(--track); overflow: hidden;
    & i { display: block; height: 100%; background: var(--grad); transition: width var(--t) var(--ease-liquid); } }
  .review-actions { display: flex; justify-content: flex-end; }

  @media (max-width: 640px) {
    .stop { grid-template-columns: 1fr; }
    .stops { padding-left: 26px; margin-left: 14px; }
    .stop-dot { left: -42px; }
    .review-actions .pill { width: 100%; }
  }
}