/* PlayDeck course — premium reader */
:root {
  --bg: #fbfbfd; --panel: #fff; --ink: #100f1a; --ink2: #3b3a4b; --muted: #6c6b7e; --soft: #9c9bad;
  --line: #ecebf3; --line2: #e2e0ee; --accent: #6d4aff; --accent2: #8b5cf6; --tint: #f6f4ff; --tint2: #ece7ff;
  --code-bg: #0c0a16; --maxw: 720px; --side: 286px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--ink); font-family: var(--font); -webkit-font-smoothing: antialiased; }
a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent2); }

/* top bar */
.cx-top { position: sticky; top: 0; z-index: 30; display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 13px 26px; background: rgba(251,251,253,.82); backdrop-filter: saturate(180%) blur(14px); border-bottom: 1px solid var(--line); }
.cx-top .brand { display: inline-flex; align-items: center; gap: 9px; font-weight: 800; font-size: 19px; color: var(--ink); letter-spacing: -.02em; }
.cx-top nav { display: flex; align-items: center; gap: 22px; font-size: 14px; font-weight: 500; }
.cx-top nav a { color: var(--ink2); }
.cx-top nav a:hover { color: var(--ink); }
.cx-top .cta { background: var(--ink); color: #fff !important; padding: 9px 18px; border-radius: 10px; font-weight: 600; font-size: 14px; }
.cx-top .cta:hover { background: #272539; }

/* reader shell */
.cx-shell { display: grid; grid-template-columns: var(--side) minmax(0, 1fr); max-width: 1180px; margin: 0 auto; align-items: start; }
.cx-side { position: sticky; top: 59px; height: calc(100vh - 59px); overflow: auto; padding: 24px 16px 60px; border-right: 1px solid var(--line); }
.cx-side::-webkit-scrollbar { width: 8px; }
.cx-side::-webkit-scrollbar-thumb { background: var(--line2); border-radius: 8px; }
.cx-side-title { font-size: 11px; text-transform: uppercase; letter-spacing: .11em; color: var(--soft); font-weight: 700; margin: 20px 10px 8px; }
.cx-side-title:first-child { margin-top: 4px; }
.cx-ni { display: flex; gap: 9px; align-items: baseline; padding: 7px 10px; border-radius: 9px; font-size: 13.5px; color: var(--ink2); line-height: 1.45; }
.cx-ni:hover { background: var(--tint); color: var(--ink); }
.cx-ni.active { background: var(--tint2); color: var(--accent); font-weight: 600; }
.cx-ni-n { color: var(--soft); font-variant-numeric: tabular-nums; min-width: 26px; font-size: 12px; }
.cx-ni.active .cx-ni-n { color: var(--accent); }
.cx-ni .lock { margin-left: auto; font-size: 11px; color: var(--soft); }

/* content */
.cx-main { padding: 44px 56px 100px; min-width: 0; }
.cx-crumb { font-size: 13px; color: var(--soft); margin-bottom: 18px; }
.cx-crumb a { color: var(--soft); }
.cx-crumb a:hover { color: var(--ink); }
.cx-eyebrow { display: inline-block; font-size: 12px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--accent); margin-bottom: 12px; }
.cx-main h1 { font-size: clamp(30px, 4vw, 43px); line-height: 1.08; letter-spacing: -.03em; margin: 0 0 26px; color: var(--ink); max-width: var(--maxw); }

.cx-article { max-width: var(--maxw); font-size: 17.5px; line-height: 1.76; color: var(--ink2); }
.cx-article > *:first-child { margin-top: 0; }
.cx-article h2 { font-size: 25px; line-height: 1.2; letter-spacing: -.02em; color: var(--ink); margin: 46px 0 14px; }
.cx-article h3 { font-size: 19px; color: var(--ink); margin: 30px 0 8px; }
.cx-article p { margin: 0 0 20px; }
.cx-article strong { color: var(--ink); font-weight: 650; }
.cx-article a { font-weight: 500; border-bottom: 1px solid var(--line2); }
.cx-article a:hover { border-color: var(--accent); }
.cx-article ul, .cx-article ol { margin: 0 0 20px; padding-left: 24px; }
.cx-article li { margin: 8px 0; }
.cx-article li::marker { color: var(--soft); }
.cx-article hr { border: 0; border-top: 1px solid var(--line); margin: 38px 0; }

/* code blocks with window chrome */
.cx-article pre { background: var(--code-bg) !important; border-radius: 14px; padding: 44px 20px 20px !important; overflow: auto; margin: 0 0 24px; position: relative; border: 1px solid #201b34; box-shadow: 0 18px 44px -22px rgba(40,18,90,.55); }
.cx-article pre::before { content: ""; position: absolute; top: 16px; left: 18px; width: 11px; height: 11px; border-radius: 50%; background: #ff5f57; box-shadow: 19px 0 #febc2e, 38px 0 #28c840; }
.cx-article pre code { font-family: var(--mono); font-size: 13.5px; line-height: 1.7; background: none !important; padding: 0; border: 0; text-shadow: none !important; }
.cx-article :not(pre) > code { font-family: var(--mono); font-size: .87em; background: var(--tint2); color: #5b3df0; padding: 2px 6px; border-radius: 6px; border: 1px solid var(--line2); white-space: nowrap; }

/* callout + details */
.cx-article blockquote { margin: 0 0 24px; padding: 16px 18px 16px 20px; background: var(--tint); border: 1px solid var(--line2); border-left: 3px solid var(--accent); border-radius: 0 12px 12px 0; color: var(--ink2); font-size: 16.5px; }
.cx-article blockquote p { margin: 0; }
.cx-article details { margin: 0 0 24px; border: 1px solid var(--line2); border-radius: 12px; padding: 14px 18px; background: var(--panel); }
.cx-article summary { cursor: pointer; font-weight: 600; color: var(--ink); }

/* pager */
.cx-pager { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin: 52px 0 0; max-width: var(--maxw); }
.cx-pg { border: 1px solid var(--line); border-radius: 14px; padding: 15px 18px; background: var(--panel); transition: .15s; }
.cx-pg:hover { border-color: var(--accent); box-shadow: 0 10px 28px -16px rgba(80,40,200,.4); transform: translateY(-1px); }
.cx-pg .dir { font-size: 12px; color: var(--soft); font-weight: 600; }
.cx-pg .t { font-weight: 650; color: var(--ink); margin-top: 4px; font-size: 15px; }
.cx-pg.next { text-align: right; grid-column: 2; }
.cx-pg.only-next { grid-column: 2; }

/* finish/cta */
.cx-finish { margin: 40px 0 0; max-width: var(--maxw); background: linear-gradient(135deg, #18142c, #271c45); border-radius: 18px; padding: 28px 30px; color: #fff; }
.cx-finish h3 { margin: 0 0 6px; font-size: 21px; letter-spacing: -.01em; }
.cx-finish p { margin: 0 0 16px; color: #cfc7e6; font-size: 14.5px; line-height: 1.6; }
.cx-finish a { display: inline-flex; background: #fff; color: #18142c !important; font-weight: 700; padding: 11px 22px; border-radius: 10px; }
.cx-finish a:hover { background: #efeaff; }

footer.cx-foot { border-top: 1px solid var(--line); padding: 32px 26px; text-align: center; color: var(--soft); font-size: 13px; }
footer.cx-foot a { color: var(--muted); }
footer.cx-foot .disc { font-size: 12px; max-width: 800px; margin: 9px auto 0; line-height: 1.55; }

/* ===== hub (course landing) ===== */
.cx-hub { max-width: 940px; margin: 0 auto; padding: 52px 26px 100px; }
.cx-hub .crumb { font-size: 13px; color: var(--soft); margin-bottom: 22px; }
.cx-hub .eyebrow { display: inline-block; font-size: 12px; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; color: var(--accent); margin-bottom: 14px; }
.cx-hub h1 { font-size: clamp(34px, 5vw, 54px); line-height: 1.05; letter-spacing: -.035em; margin: 0 0 20px; color: var(--ink); max-width: 760px; }
.cx-hub .lead { font-size: 19px; line-height: 1.62; color: var(--ink2); max-width: 680px; margin: 0 0 26px; }
.cx-hub .lead b { color: var(--ink); font-weight: 650; }
.cx-hub .whatis { border: 1px solid var(--line2); background: var(--tint); border-radius: 16px; padding: 18px 20px; font-size: 14.5px; color: var(--ink2); line-height: 1.65; margin: 0 0 6px; }
.cx-hub .whatis b { color: var(--ink); }
.cx-hub h2 { font-size: 14px; text-transform: uppercase; letter-spacing: .08em; color: var(--soft); font-weight: 700; margin: 52px 0 6px; }
.cx-hub .sub { color: var(--muted); margin: 0 0 18px; font-size: 15.5px; }
.cx-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.cx-tile { border: 1px solid var(--line); border-radius: 16px; padding: 18px 20px; background: var(--panel); }
.cx-tile b { color: var(--ink); display: block; margin-bottom: 4px; font-size: 15px; }
.cx-tile span { color: var(--muted); font-size: 14px; line-height: 1.55; }

.cx-track { display: flex; flex-direction: column; gap: 8px; }
.cx-row { display: flex; align-items: center; gap: 16px; border: 1px solid var(--line); border-radius: 14px; padding: 15px 18px; background: var(--panel); transition: .15s; }
.cx-row:hover { border-color: var(--accent); box-shadow: 0 10px 30px -18px rgba(80,40,200,.45); transform: translateY(-1px); }
.cx-row .num { font-variant-numeric: tabular-nums; font-weight: 700; color: var(--soft); font-size: 13px; min-width: 70px; }
.cx-row .body { min-width: 0; flex: 1; }
.cx-row .ttl { display: block; font-weight: 650; color: var(--ink); font-size: 16px; }
.cx-row .dsc { display: block; color: var(--muted); font-size: 14px; margin-top: 3px; line-height: 1.5; }
.cx-row .arrow { color: var(--soft); font-size: 18px; }
.cx-row:hover .arrow { color: var(--accent); }
.badge { font-size: 11px; font-weight: 700; border-radius: 999px; padding: 3px 9px; white-space: nowrap; }
.badge.free { color: #0a7d4b; background: #d8f5e6; }
.badge.mem { color: #6d4aff; background: #ece7ff; }

.cx-hub .finish { margin-top: 56px; }

@media (max-width: 900px) {
  .cx-shell { grid-template-columns: 1fr; }
  .cx-side { display: none; }
  .cx-main { padding: 30px 22px 72px; }
  .cx-grid { grid-template-columns: 1fr; }
  .cx-pager { grid-template-columns: 1fr; }
  .cx-pg.next, .cx-pg.only-next { grid-column: 1; text-align: left; }
}