/* Learn: shelves, topic cards and lesson articles */
/* ================= IT Knowledge ================= */
.ln-shelf { margin-top: clamp(40px, 6vw, 72px); display: grid; grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr); gap: 16px; align-items: stretch; }
.ln-folder { --fg: var(--ink); position: relative; display: grid; grid-template-rows: auto auto 1fr auto; gap: 10px; text-align: left; padding: 30px 26px 22px; border: 0; border-radius: 6px 22px 22px 22px;
  background: var(--surface); color: var(--ink); font: inherit; cursor: pointer; overflow: visible; transition: transform .45s cubic-bezier(.3,1.4,.5,1), box-shadow .3s; }
.ln-folder .lf-tab { position: absolute; left: 0; top: -14px; width: 38%; height: 16px; border-radius: 12px 16px 0 0; background: var(--surface); }
.ln-folder:hover { transform: translateY(-4px); box-shadow: 0 18px 40px rgba(0,0,0,.08); }
.ln-folder .lf-ic { width: 44px; height: 44px; display: grid; place-items: center; border-radius: 14px; background: var(--ink); color: var(--ground); }
.ln-folder .lf-ic .li { width: 24px; height: 24px; }
.ln-folder .lf-name { font-family: var(--display); font-size: clamp(26px, 3.4vw, 36px); letter-spacing: -.035em; line-height: 1.05; }
.ln-folder .lf-desc { color: var(--muted); font-size: 15px; max-width: 36ch; }
.ln-folder .lf-peek { display: flex; gap: 8px; margin-top: 6px; }
.ln-folder .lf-peek span { width: 38px; height: 38px; border-radius: 12px; background: var(--ground); display: grid; place-items: center; color: var(--ink); transition: transform .45s cubic-bezier(.3,1.5,.5,1); transition-delay: calc(var(--k, 0) * 30ms); }
.ln-folder .lf-peek span:nth-child(2) { --k: 1; } .ln-folder .lf-peek span:nth-child(3) { --k: 2; } .ln-folder .lf-peek span:nth-child(4) { --k: 3; } .ln-folder .lf-peek span:nth-child(5) { --k: 4; }
.ln-folder:hover .lf-peek span { transform: translateY(-6px) rotate(-4deg); }
.ln-folder .lf-peek .li { width: 19px; height: 19px; }
.ln-folder .lf-foot { display: flex; justify-content: space-between; align-items: center; font-size: 13px; color: var(--muted); margin-top: 6px; }
.ln-folder .lf-open { color: var(--ink); font-weight: 500; display: inline-flex; gap: 6px; }
.ln-folder .lf-open::after { content: "→"; transition: transform .25s; }
.ln-folder:hover .lf-open::after { transform: translateX(4px); }
.ln-soon { border: 1px dashed var(--hair); border-radius: 22px; display: grid; place-items: center; align-content: center; gap: 10px; padding: 24px; color: var(--muted); font-size: 14px; text-align: center; }
.ln-soon .lf-ic { width: 40px; height: 40px; display: grid; place-items: center; border-radius: 12px; background: var(--surface); opacity: .7; }
.ln-soon .li { width: 22px; height: 22px; }
@media (max-width: 760px) { .ln-shelf { grid-template-columns: 1fr; } .ln-soon { padding: 18px; } }

.ln-page { position: relative; z-index: 1; min-height: 70vh; padding-top: calc(72px + env(safe-area-inset-top, 0px)); }
.ln-bar { position: relative; z-index: 2; display: flex; align-items: center; gap: 12px; width: min(1040px, 100%); margin: 0 auto; padding: 18px clamp(16px, 4vw, 40px) 0;
}
.ln-bar .ln-brand { display: inline-flex; align-items: center; gap: 8px; font-family: var(--display); font-size: 17px; letter-spacing: -.02em; white-space: nowrap; }
.ln-bar .ln-brand .mk { width: 9px; height: 16px; background: currentColor; }
.ln-crumbs { display: flex; align-items: center; gap: 6px; flex: 1; min-width: 0; overflow-x: auto; scrollbar-width: none; font-size: 14px; }
.ln-crumbs::-webkit-scrollbar { display: none; }
.ln-crumb { white-space: nowrap; color: var(--muted); background: none; border: 0; padding: 6px 4px; font: inherit; }
a.ln-crumb { text-decoration: none; } a.ln-crumb:hover { color: var(--ink); }
.ln-crumb + .ln-crumb::before { content: "/"; margin-right: 8px; color: var(--hair); }
.ln-crumb[aria-current="page"] { color: var(--ink); }
.ln-x { width: 40px; height: 40px; flex: none; border-radius: 999px; border: 1px solid var(--hair); background: transparent; color: inherit; font: 400 22px/1 var(--body); cursor: pointer; }
.ln-x:hover { border-color: var(--muted); }
.ln-body { width: min(1040px, 100%); margin: 0 auto; padding: clamp(28px, 5vw, 56px) clamp(16px, 4vw, 40px) 80px; }
.ln-head, .ln-ahead { display: grid; grid-template-columns: auto 1fr; gap: 20px; align-items: start; margin-bottom: clamp(28px, 4vw, 44px); }
.ln-bigic { width: 64px; height: 64px; border-radius: 20px; background: var(--ink); color: var(--ground); display: grid; place-items: center; }
.ln-bigic .li { width: 32px; height: 32px; }
.ln-eyebrow { margin: 0 0 6px; font-size: 12px; font-weight: 600; letter-spacing: .14em; text-transform: uppercase; color: var(--muted); }
.ln-page h1 { margin: 0; font-family: var(--display); font-weight: 400; font-size: clamp(36px, 6vw, 64px); letter-spacing: -.045em; line-height: 1.02; text-wrap: balance; }
.ln-lede { margin: 12px 0 0; color: var(--muted); font-size: clamp(16px, 2vw, 19px); max-width: 44rem; text-wrap: pretty; }
.ln-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 12px; }
.ln-topic { display: grid; grid-template-rows: auto auto 1fr auto; gap: 8px; text-align: left; padding: 18px 18px 16px; border: 1px solid transparent; border-radius: 18px; background: var(--surface); color: var(--ink); font: inherit; cursor: pointer;
  transition: transform .4s cubic-bezier(.3,1.4,.5,1), border-color .2s; }
.ln-topic:hover { transform: translateY(-3px); border-color: var(--hair); }
.ln-topic .lt-top { display: flex; justify-content: space-between; align-items: center; margin-bottom: 4px; }
.ln-topic .lt-ic { width: 40px; height: 40px; border-radius: 12px; background: var(--ground); display: grid; place-items: center; transition: background .25s, color .25s, transform .45s cubic-bezier(.3,1.5,.5,1); }
.ln-topic:hover .lt-ic { background: var(--ink); color: var(--ground); transform: rotate(-6deg) scale(1.06); }
.ln-topic .lt-ic .li { width: 21px; height: 21px; }
.ln-topic .lt-no { font-size: 12px; color: var(--muted); font-variant-numeric: tabular-nums; }
.ln-topic .lt-name { font-family: var(--display); font-size: 19px; letter-spacing: -.02em; line-height: 1.2; }
.ln-topic .lt-lead { font-size: 14px; color: var(--muted); line-height: 1.45; }
.ln-topic .lt-foot { display: flex; justify-content: space-between; font-size: 12px; color: var(--muted); margin-top: 6px; }
.ln-topic .lt-go { color: var(--ink); transition: transform .25s; } .ln-topic:hover .lt-go { transform: translateX(4px); }

.ln-article { max-width: 720px; margin: 0 auto; }
.ln-block { margin: 0 0 30px; }
.ln-block h2 { margin: 0 0 12px; font-family: var(--display); font-weight: 500; font-size: 22px; letter-spacing: -.02em; }
.ln-block p { margin: 0; font-size: 17px; line-height: 1.65; max-width: 66ch; }
.ln-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
.ln-list li { display: grid; grid-template-columns: 14px 1fr; gap: 12px; align-items: baseline; font-size: 16.5px; line-height: 1.55; }
.ln-list .mk, .ln-kt .mk { width: 8px; height: 14px; background: currentColor; transform: translateY(2px); }
.ln-steps { list-style: none; margin: 0; padding: 0; display: grid; gap: 0; counter-reset: s; }
.ln-steps li { position: relative; display: grid; grid-template-columns: 32px 1fr; gap: 14px; padding: 0 0 18px; font-size: 16.5px; line-height: 1.5; }
.ln-steps li:not(:last-child)::before { content: ""; position: absolute; left: 15.5px; top: 32px; bottom: 2px; width: 1px; background: var(--hair); }
.ln-steps .ls-n { width: 32px; height: 32px; border-radius: 50%; background: var(--ink); color: var(--ground); display: grid; place-items: center; font-size: 14px; font-weight: 600; font-variant-numeric: tabular-nums; }
.ln-steps li > span:last-child { padding-top: 4px; }
.ln-layers { display: grid; gap: 6px; }
.ll { display: grid; grid-template-columns: 34px 1fr auto; gap: 12px; align-items: center; padding: 12px 14px; border-radius: 12px;
  background: color-mix(in srgb, var(--ink) calc(4% + var(--n) * 1.6%), var(--surface)); }
.ll-n { width: 34px; height: 34px; border-radius: 10px; background: var(--ground); display: grid; place-items: center; font-weight: 600; font-variant-numeric: tabular-nums; }
.ll-name { font-size: 16px; font-weight: 500; }
.ll-ex { font-size: 13px; color: var(--muted); text-align: right; }
@media (max-width: 520px) { .ll { grid-template-columns: 34px 1fr; } .ll-ex { grid-column: 2; text-align: left; margin-top: -6px; } }
.ln-tablewrap { overflow-x: auto; border-radius: 14px; border: 1px solid var(--hair); }
.ln-table { width: 100%; border-collapse: collapse; font-size: 15px; font-variant-numeric: tabular-nums; }
.ln-table th { text-align: left; font-size: 12px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); padding: 12px 14px; background: var(--surface); }
.ln-table td { padding: 12px 14px; border-top: 1px solid var(--hair); }
.ln-table td:first-child { font-weight: 500; white-space: nowrap; }
.ln-key { margin: 8px 0 16px; padding: 20px 22px; border-radius: 18px; background: var(--ink); color: var(--ground); }
.ln-key ul { margin: 10px 0 0; padding-left: 18px; display: grid; gap: 8px; font-size: 16px; line-height: 1.5; }
.ln-kt { margin: 0; display: flex; align-items: center; gap: 8px; font-size: 12px; font-weight: 600; letter-spacing: .14em; text-transform: uppercase; opacity: .8; }
.ln-fact { margin: 0 0 36px; padding: 18px 22px; border-radius: 18px; border: 1px dashed var(--hair); }
.ln-fact .ln-kt { color: var(--muted); }
.ln-fact p:last-child { margin: 8px 0 0; font-size: 16px; line-height: 1.55; }
.ln-pager { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.ln-pg { display: grid; gap: 4px; text-align: left; padding: 16px 18px; border-radius: 16px; border: 1px solid var(--hair); background: transparent; color: var(--ink); font: inherit; cursor: pointer; transition: border-color .2s, transform .3s cubic-bezier(.3,1.4,.5,1); }
.ln-pg.nx { text-align: right; }
.ln-pg:hover { border-color: var(--muted); transform: translateY(-2px); }
.ln-pg small { font-size: 12px; color: var(--muted); }
.ln-pg span { font-family: var(--display); font-size: 17px; letter-spacing: -.01em; }
@media (max-width: 520px) { .ln-head, .ln-ahead { grid-template-columns: 1fr; gap: 14px; } .ln-bar .ln-brand { display: none; } .ln-pager { grid-template-columns: 1fr; } .ln-pg.nx { text-align: left; } }
@media (prefers-reduced-motion: reduce) { .ln-folder, .ln-topic, .ln-pg, .ln-folder .lf-peek span, .ln-topic .lt-ic { transition: none; } }

/* real pages: topic cards and pager are links now */
a.ln-folder, a.ln-topic, a.ln-pg { text-decoration: none; }
.ln-folder:focus-visible, .ln-topic:focus-visible, .ln-pg:focus-visible { outline: 2px solid var(--ink); outline-offset: 3px; }
.ln-lede2 { font-size: 15px; margin-top: 8px; }
.ln-more { margin-top: 22px; display: flex; flex-wrap: wrap; align-items: center; gap: 10px 12px; }
.ln-more-t { flex-basis: 100%; margin: 12px 0 4px; font-size: 14px; color: var(--muted); }
.ln-more-t > span:first-child { color: var(--ink); font-weight: 500; margin-right: 6px; }
.ln-more-a { display: inline-flex; align-items: center; gap: 10px; padding: 12px 16px; border-radius: 16px; background: var(--surface); color: var(--ink); text-decoration: none; font-size: 15px; transition: transform .3s cubic-bezier(.3,1.4,.5,1); }
.ln-more-a:hover { transform: translateY(-2px); }
.ln-more-a .ai { width: 18px; height: 18px; }

/* ---------- colour: each folder / lesson carries its own accent (--acc, set in render.js) ---------- */
.ln-folder { background: linear-gradient(150deg, color-mix(in srgb, var(--acc) 16%, var(--surface)), var(--surface) 70%); }
.ln-folder .lf-tab { background: color-mix(in srgb, var(--acc) 16%, var(--surface)); }
.ln-folder .lf-ic, .ln-head .ln-bigic { background: var(--acc); color: #fff; box-shadow: 0 10px 22px -10px var(--acc); }
.ln-folder .lf-peek span { background: color-mix(in srgb, var(--acc) 18%, var(--ground)); color: var(--acc); }
.ln-folder:hover { box-shadow: 0 18px 40px -18px color-mix(in srgb, var(--acc) 60%, transparent); }
.ln-topic { background: color-mix(in srgb, var(--acc) 8%, var(--surface)); }
.ln-topic .lt-ic { background: var(--acc); color: #fff; }
.ln-topic:hover { border-color: color-mix(in srgb, var(--acc) 55%, transparent); }
.ln-topic:hover .lt-ic { background: var(--acc); color: #fff; }
.ln-topic .lt-no { color: var(--acc); font-weight: 600; }
.ln-article .ln-bigic { background: var(--acc); color: #fff; box-shadow: 0 12px 26px -12px var(--acc); }
.ln-article .ln-eyebrow { color: var(--acc); }
.ln-article .ln-block h2 { display: flex; align-items: center; gap: 10px; }
.ln-article .ln-block h2::before { content: ""; width: 6px; height: 20px; border-radius: 3px; background: var(--acc); }
.ln-article .ln-list .mk { background: var(--acc); }
.ln-article .ln-steps .ls-n { background: var(--acc); color: #fff; }
.ln-article .ll { background: color-mix(in srgb, var(--acc) calc(6% + var(--n) * 3%), var(--surface)); }
.ln-article .ll-n { color: var(--acc); }
.ln-article .ln-table th { background: color-mix(in srgb, var(--acc) 12%, var(--surface)); }
.ln-article .ln-key { background: linear-gradient(140deg, var(--acc), color-mix(in srgb, var(--acc) 55%, #111114)); color: #fff; }
.ln-article .ln-fact { border: 0; background: color-mix(in srgb, var(--acc) 10%, var(--surface)); }
.ln-article .ln-fact .ln-kt { color: var(--acc); }
.ln-article .ln-pg:hover { border-color: var(--acc); }