/* Article page: long-form layout on top of ../../styles.css (same tokens, same type). */

  /* Top nav and footer */
  .topnav { padding: 24px 0; border-bottom: 1px solid var(--border); }
  .topnav .wrap { justify-content: space-between; }
  .topnav .home { color: var(--cream); font-weight: 600; }

  /* Article column: prose holds a reading measure, figures use the full .wrap */
  .article { padding-top: 56px; padding-bottom: 88px; font-size: 18px; line-height: 1.7; }
  .article h1 { font-size: clamp(32px, 5.4vw, 48px); line-height: 1.1; margin-bottom: 22px; max-width: 780px; }
  .byline { display: flex; flex-wrap: wrap; gap: 2px 20px; color: var(--muted); font-size: 14.5px; margin-bottom: 40px; }
  .toc { margin: 0 0 8px; font-size: 14px; line-height: 1.55; }
  .toc ol { list-style: none; margin: 0; padding: 0 0 0 14px; border-left: 2px solid var(--border); }
  .toc li { margin: 0; padding: 0; }
  .toc a { color: var(--muted); text-decoration: none; }
  .toc a:hover, .toc a:focus-visible { color: var(--accent); }
  .article > p, .article > ul, .article > ol { max-width: 680px; margin-bottom: 1.15em; }
  .article > h2 { font-size: 34px; line-height: 1.15; margin: 80px 0 24px; max-width: 760px; }
  .article > h3 { color: var(--cream); font-size: 22px; font-weight: 600; letter-spacing: -0.01em; line-height: 1.3; margin: 48px 0 14px; }
  .article > h4 { color: var(--cream); font-size: 18px; font-weight: 600; line-height: 1.35; margin: 32px 0 10px; max-width: 680px; }
  .article > p code, .article li code { font: 0.86em ui-monospace, "SF Mono", Menlo, Consolas, monospace; color: var(--cream); background: var(--card); border: 1px solid var(--border); border-radius: 5px; padding: 0.08em 0.32em; overflow-wrap: anywhere; }
  .article > ul, .article > ol { padding-left: 1.3em; }
  .article li { margin-bottom: 0.55em; padding-left: 0.2em; }
  .article li::marker { color: var(--muted); }
  .article strong { color: var(--cream); font-weight: 600; }
  .article > p a { color: var(--accent); text-decoration: underline; text-underline-offset: 3px; text-decoration-thickness: 1px; overflow-wrap: anywhere; }

  /* Figures: generous rhythm, captions quiet */
  .article > figure.fig, .article > figure.rp, .article > figure.ba { margin: 52px 0; }
  .article > h2 + figure.fig, .article > h2 + figure.rp, .article > h3 + figure.fig { margin-top: 28px; }
  .article figure figcaption { font-size: 14.5px; line-height: 1.55; color: var(--muted); }
  .fig[data-fig="claims"] > .fig-replay { display: none; }

  /* Converted core diagrams: drawn on a light ground, framed as an image in both modes */
  .fig.fig-diagram { background: #f6f6f2; border: 1px solid var(--border); border-radius: 12px; padding: 14px; color-scheme: light;
    --f-bg: #f6f6f2; --f-alt: #ecece6; --f-card: #ffffff; --f-border: #d8d8d0; --f-head: #141414; --f-body: #333330;
    --f-muted: #8a8a82; --f-accent: #b13a32; --f-ok: #2f7d4f; }
  .fig-diagram svg text:not([fill]) { fill: inherit; }
  /* a figure may carry a phone-first drawing beside its wide svg: one of the two shows at a time */
  .fig svg.fig-phone { display: none; }

  /* Wide SVG figures: they pan inside their frame on phones, and every width gets a full-screen view */
  .pan-hint { display: none; }
  .fig-full { margin-top: 6px; padding: 2px 0; border: 0; background: none; color: var(--f-muted, var(--muted)); font: inherit; font-size: .9rem; cursor: pointer; text-decoration: underline; text-underline-offset: 3px; }
  .fig-full:hover, .fig-full:focus-visible { color: var(--f-head, var(--cream)); }
  .fig-replay + .fig-full { margin-left: 18px; }
  .rp > .fig-full { margin: -6px 16px 14px; }
  @media (max-width: 699px) {
    .pan { overflow-x: auto; -webkit-overflow-scrolling: touch; scroll-snap-type: x proximity; overscroll-behavior-x: contain; }
    .pan > svg { min-width: 720px; scroll-snap-align: start; }
    .pan-hint { display: block; margin: 0 0 6px; font-size: 13px; line-height: 1.4; color: var(--f-muted, var(--muted)); }
    .rp > .pan-hint { margin: 12px 16px 0; }
    /* the three core diagrams fit the width on phones: the shape first, Full screen for the detail */
    .fig-diagram .pan { overflow: visible; }
    .fig-diagram .pan > svg { min-width: 0; }
    .fig svg.fig-desk { display: none; }
    .fig svg.fig-phone { display: block; }
    .pan > svg.fig-phone { min-width: 0; }
  }

  /* Full-screen figure dialog */
  html.fs-lock { overflow: hidden; }
  .fs { width: min(calc(100vw - 24px), 1440px); height: calc(100vh - 24px); height: calc(100dvh - 24px); max-width: none; max-height: none; margin: auto; padding: 0; border: 1px solid var(--border); border-radius: 12px; background: var(--bg); color: var(--body); overflow: hidden; }
  .fs[open] { display: flex; flex-direction: column; }
  .fs::backdrop { background: rgba(8, 8, 8, .8); }
  .fs-bar { display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 10px 12px 10px 16px; border-bottom: 1px solid var(--border); font-size: 13px; line-height: 1.4; color: var(--muted); }
  .fs-close { flex: none; font: inherit; font-size: 14px; color: var(--cream); background: var(--card); border: 1px solid var(--border); border-radius: 999px; padding: 6px 16px; cursor: pointer; }
  .fs-close:hover, .fs-close:focus-visible { border-color: var(--accent); color: var(--accent); }
  .fs-body { flex: 1; min-height: 0; overflow: auto; padding: 16px; touch-action: pan-x pan-y pinch-zoom; overscroll-behavior: contain; -webkit-overflow-scrolling: touch; }
  .fs-body:focus-visible { outline: 2px solid var(--muted); outline-offset: -2px; }
  .fs-body > figure { width: max(100%, 940px); margin: 0; }
  .fs .pan { overflow: visible; }
  .fs .pan > svg { min-width: 0; }
  .fs .fig svg.fig-desk { display: block; }   /* full screen always shows the desktop drawing, for pinch-zoom */
  .fs .fig svg.fig-phone { display: none; }
  .fs .pan-hint, .fs .fig-full { display: none; }
  .fs figure figcaption { font-size: 14.5px; line-height: 1.55; color: var(--muted); }
  .fs .rp figcaption { padding: 0 16px 14px; }

  /* Summary for AI assistants: one line, closed by default */
  .tldr { margin: 8px 0 26px; max-width: 680px; background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 10px 12px 10px 18px; }
  .tldr-head { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 8px 16px; }
  .tldr.open .tldr-head { margin-bottom: 12px; }
  .tldr-actions { display: flex; align-items: center; gap: 8px; }
  .tldr-toggle { font: inherit; font-size: 13.5px; line-height: 1.3; cursor: pointer; border-radius: 999px; padding: 6px 14px; min-width: 4.6em; border: 1px solid var(--border); background: var(--card); color: var(--cream); }
  .tldr-toggle:hover { border-color: var(--muted); }
  .tldr-toggle:focus-visible { outline: 2px solid var(--cream); outline-offset: 2px; }
  .tldr-label { font-size: 12px; letter-spacing: 0.2em; text-transform: uppercase; color: var(--accent); font-weight: 600; }
  .tldr-copy { font: inherit; font-size: 13.5px; line-height: 1.3; cursor: pointer; border-radius: 999px; padding: 6px 14px; border: 1px solid var(--accent); background: var(--accent); color: #fff; }
  .tldr-copy:hover { filter: brightness(1.08); }
  .tldr-copy:focus-visible { outline: 2px solid var(--cream); outline-offset: 2px; }
  .tldr pre { margin: 0; padding: 14px 16px; max-height: 24em; overflow: auto; white-space: pre-wrap; overflow-wrap: anywhere; font: 12.5px/1.6 ui-monospace, "SF Mono", Menlo, Consolas, monospace; color: var(--body); background: var(--bg); border: 1px solid var(--border); border-radius: 8px; }

  /* The gate code, excerpted at the pinned commit */
  .article > figure.cg { margin: 28px 0 40px; }
  .cg-pre { margin: 0; padding: 14px 0; overflow-x: auto; background: var(--card); border: 1px solid var(--border); border-radius: 10px; font: 13.5px/1.7 ui-monospace, "SF Mono", Menlo, Consolas, monospace; color: var(--cream); -webkit-overflow-scrolling: touch; }
  .cg-pre code { font: inherit; display: block; padding-right: 16px; }
  .cg-ln { display: flex; min-height: 1.7em; }
  .cg-no { flex: none; box-sizing: border-box; width: 60px; padding: 0 14px 0 6px; text-align: right; color: var(--muted); user-select: none; -webkit-user-select: none; }
  .cg-tx { flex: 1; min-width: 0; white-space: pre; }
  .cg-file { display: block; padding: 0 16px 2px 60px; font-family: 'Inter', system-ui, sans-serif; font-size: 12.5px; line-height: 1.6; letter-spacing: .01em; color: var(--muted); white-space: normal; }
  .cg-hc { font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace; font-size: 12px; letter-spacing: 0; }
  .cg-gap { display: block; height: 12px; }
  @media (max-width: 699px) { .cg-tx { white-space: pre-wrap; overflow-wrap: anywhere; padding-left: 2ch; text-indent: -2ch; } }
  .article figure.cg figcaption { margin-top: 8px; font-size: 13.5px; }
  .cg-src a { color: var(--accent); text-decoration: underline; text-underline-offset: 3px; text-decoration-thickness: 1px; overflow-wrap: anywhere; }

  /* The claims card closes the page as an appendix */
  .article > h2.appendix-h { margin-top: 104px; padding-top: 30px; border-top: 1px solid var(--border); font-size: 24px; }
  .article > h2.appendix-h::before { content: "Appendix"; display: block; margin-bottom: 10px; font-size: 12px; letter-spacing: 0.2em; text-transform: uppercase; color: var(--accent); font-weight: 600; }
  .article > h2.appendix-h + figure.fig { margin-top: 20px; }

  /* Replay figure (leaderboard rank timeline), namespaced .rp */
  .rp { --rp-head: var(--cream); --rp-gold: #e0b13a; --rp-grey: #8a8a82; --rp-grey-op: .25; --rp-hector: #9b9b93; background: var(--card); border: 1px solid var(--border); border-radius: 10px; overflow: hidden; }
  @media (prefers-color-scheme: dark) { .rp { --rp-grey-op: .3; --rp-hector: #66665f; } }
  .rp svg { display: block; width: 100%; height: auto; }
  .rp svg text { font-family: inherit; }
  .rp-ctl { display: flex; align-items: center; gap: 10px; padding: 10px 16px 12px; }
  .rp-ctl button { font: 500 14px 'Inter', system-ui, sans-serif; color: var(--rp-head); background: var(--card); border: 1px solid var(--border); border-radius: 8px; padding: 8px 14px; min-width: 84px; cursor: pointer; }
  .rp-ctl button:hover { border-color: var(--muted); }
  .rp-ctl button:focus-visible, .rp-ctl input:focus-visible { outline: 2px solid var(--rp-gold); outline-offset: 2px; }
  .rp-ctl input { flex: 1; min-width: 0; accent-color: var(--rp-gold); }
  .article .rp figcaption { padding: 0 16px 14px; }
  .rp .ev { opacity: 0; }
  .rp .ev.on { opacity: 1; }
  .rp.anim .ev { transition: opacity .25s ease; }
  .rp.anim .ev .dot { transform-box: fill-box; transform-origin: center; transform: scale(.2); transition: transform .3s cubic-bezier(.3, 1.6, .5, 1); }
  .rp.anim .ev.on .dot { transform: scale(1); }
  .rp.rm .rp-ctl button { display: none; }
  .rp .tk { opacity: 0; }
  .rp .tk.on { opacity: 1; }
  .rp .tk-late.on { opacity: .55; }
  .rp .tk-h { fill: var(--rp-hector); }
  .rp .tk-t { fill: var(--rp-gold); }
  .rp .tk-o { fill: var(--muted); }
  .rp.anim .tk { transform-box: fill-box; transform-origin: 50% 100%; transform: scaleY(.2); transition: opacity .2s ease, transform .25s ease; }
  .rp.anim .tk.on { transform: none; }
  .rp .gaplab { paint-order: stroke; stroke: var(--card); stroke-width: 5px; stroke-linejoin: round; }

  /* Briefing anatomy figure, namespaced .ba */
  .ba { --ba-hl: rgba(224,177,58,.28); --ba-gold: #e0b13a;
    --ba-c-goal: #3f74a8; --ba-c-authority: #b13a32; --ba-c-rules: #7d55a8; --ba-c-plan: #2f8a62; --ba-c-checkpoints: #b8691f;
    font-size: 15px; line-height: 1.5; color: var(--body); }
  @media (prefers-color-scheme: dark) {
    .ba { --ba-hl: rgba(224,177,58,.2); --ba-c-goal: #6aa3d6; --ba-c-authority: #d9776d; --ba-c-rules: #a98bd1; --ba-c-plan: #5cc193; --ba-c-checkpoints: #e09550; }
  }
  .ba * { box-sizing: border-box; }
  .ba .ba-head { margin: 0 0 16px; }
  .ba .ba-title { display: block; font-size: 19px; font-weight: 600; color: var(--cream); margin: 0 0 4px; letter-spacing: -0.01em; line-height: 1.35; }
  .ba .ba-cap { display: block; }
  .ba-card { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr); background: var(--card); border: 1px solid var(--border); border-radius: 10px; overflow: hidden; }
  .ba-doc { height: 560px; overflow-y: auto; position: relative; padding: 14px 0; background: var(--card); border-right: 1px solid var(--border); font: 15px/1.55 ui-monospace, "SF Mono", Menlo, monospace; color: var(--cream); }
  .ba-ln { display: flex; gap: 12px; padding: 3px 14px 3px 0; transition: opacity .3s, background .3s; }
  .ba-no { flex: 0 0 38px; text-align: right; color: var(--muted); user-select: none; font-size: 13px; padding-top: 1px; }
  .ba-tx { flex: 1; min-width: 0; white-space: pre-wrap; overflow-wrap: anywhere; }
  .ba-ln.ctx .ba-tx, .ba-ln.gap .ba-tx { color: var(--muted); }
  .ba-js .ba-ln { opacity: .45; }
  .ba-js .ba-ln.on { opacity: 1; background: var(--ba-hl); box-shadow: inset 3px 0 0 var(--ba-gold); }
  .ba-js .ba-ln.gap, .ba-js .ba-ln.ctx { opacity: .45; }
  .ba-steps { list-style: none; margin: 0; padding: 10px; display: flex; flex-direction: column; gap: 6px; background: var(--bg-alt); }
  .ba-step { all: unset; box-sizing: border-box; cursor: pointer; display: grid; grid-template-columns: auto 1fr; gap: 12px; align-items: start; width: 100%; padding: 12px 12px 14px; border-radius: 8px; border: 1px solid transparent; position: relative; overflow: hidden; }
  .ba-step:hover, .ba-step:focus-visible { border-color: var(--border); }
  .ba-step:focus-visible { outline: 2px solid var(--ba-gold); outline-offset: 1px; }
  .ba-chip { width: 28px; height: 28px; border-radius: 14px; border: 1.5px solid var(--muted); color: var(--muted); display: grid; place-items: center; font-weight: 600; font-size: 13px; background: transparent; margin-top: 1px; }
  .ba-tt { display: block; font-weight: 600; color: var(--cream); font-size: 15px; }
  .ba-an { display: block; font-size: 14px; line-height: 1.45; margin-top: 2px; }
  .ba-step[aria-selected=true] { background: var(--card); border-color: var(--border); }
  .ba-step[aria-selected=true] .ba-chip { background: var(--ba-gold); border-color: var(--ba-gold); color: #141414; }
  .ba-bar { position: absolute; left: 0; right: 0; bottom: 0; height: 3px; background: transparent; }
  .ba-bar i { display: block; height: 100%; width: 0; background: var(--ba-gold); }
  .ba-still .ba-ln { opacity: 1; }
  .ba-still .ba-ln[data-part]:not([data-part=context]) { background: color-mix(in srgb, var(--pc) 14%, transparent); box-shadow: inset 3px 0 0 var(--pc); }
  .ba-still .ba-step .ba-chip { border-color: var(--pc); color: var(--pc); }
  .ba-still .ba-bar { display: none; }
  .ba-still .ba-step[aria-selected=true] { background: transparent; border-color: transparent; }
  .ba-still .ba-step[aria-selected=true] .ba-chip { background: transparent; border-color: var(--pc); color: var(--pc); }
  .ba [data-part=goal] { --pc: var(--ba-c-goal); }
  .ba [data-part=authority] { --pc: var(--ba-c-authority); }
  .ba [data-part=rules] { --pc: var(--ba-c-rules); }
  .ba [data-part=plan] { --pc: var(--ba-c-plan); }
  .ba [data-part=checkpoints] { --pc: var(--ba-c-checkpoints); }
  @media (max-width: 640px) {
    .ba-card { grid-template-columns: 1fr; }
    .ba-doc { height: 380px; border-right: 0; border-bottom: 1px solid var(--border); font-size: 14px; }
  }

  /* Phones */
  @media (max-width: 600px) {
    .wrap { padding: 0 20px; }
    .article { padding-top: 36px; font-size: 17px; }
    .article > h2 { font-size: 27px; margin-top: 60px; }
    .article > h3 { font-size: 20px; }
    .article > figure.fig, .article > figure.rp, .article > figure.ba { margin: 40px 0; }
    .tldr { padding: 10px 10px 10px 14px; }
    .cg-pre { font-size: 12.5px; }
    .cg-no { width: 48px; padding: 0 10px 0 4px; }
    .cg-file { padding-left: 48px; }
    .article > h2.appendix-h { font-size: 22px; margin-top: 80px; }
    .tldr pre { padding: 12px; font-size: 12.5px; }
    .article .fig-diagram { padding: 8px; }
  }
  @media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
  }
  /* the repo link at the top, styled like the home page's hero links */
  .byline { align-items: center; }
  .byline a { display: inline-block; padding: 2px 12px; border: 1px solid var(--border); border-radius: 999px; color: var(--body); text-decoration: none; font-size: 14px; line-height: 1.6; overflow-wrap: anywhere; }
  .byline a:hover, .byline a:focus-visible { border-color: var(--accent); color: var(--accent); }
  /* collapsed long-form detail ({{details: NAME}}): the summary is a quiet text toggle, the prose inside keeps the measure */
  .article > details.mechanics { max-width: 680px; margin: 0 0 1.4em; }
  .mechanics > summary { display: inline-block; cursor: pointer; list-style: none; padding: 4px 0; font-size: 15.5px; font-weight: 600; color: var(--accent); text-decoration: underline; text-underline-offset: 3px; text-decoration-thickness: 1px; }
  .mechanics > summary::-webkit-details-marker { display: none; }
  .mechanics > summary::before { content: "+"; display: inline-block; width: 1.1em; text-decoration: none; }
  .mechanics[open] > summary::before { content: "\2212"; }
  .mechanics > summary:hover { text-decoration-thickness: 2px; }
  .mechanics > summary:focus-visible { outline: 2px solid var(--cream); outline-offset: 2px; border-radius: 4px; }
  .mechanics-body { margin-top: 14px; padding-left: 18px; border-left: 2px solid var(--border); }
  .mechanics-body p { margin-bottom: 1.15em; }
  .mechanics-body h4 { color: var(--cream); font-size: 18px; font-weight: 600; line-height: 1.35; margin: 28px 0 10px; }
  .mechanics-body h4:first-child { margin-top: 0; }
  .mechanics-body code { font: 0.86em ui-monospace, "SF Mono", Menlo, Consolas, monospace; color: var(--cream); background: var(--card); border: 1px solid var(--border); border-radius: 5px; padding: 0.08em 0.32em; overflow-wrap: anywhere; }
  .mechanics-body a { color: var(--accent); text-decoration: underline; text-underline-offset: 3px; text-decoration-thickness: 1px; overflow-wrap: anywhere; }
  @media (max-width: 600px) { .mechanics-body { padding-left: 14px; } }