/* Learn's pages, over the site's motion.css and site.css: their colours, type and controls, and
   only what Learn adds here, with ln- names. Light and dark follow the site's own tokens; what sits
   on a picture (the glows, the hero) uses the dark look's colours in either. */

/* the side padding of a box already held to --ln-max: never the site's --m-pad, which grows with
   the window to centre full-width content and, inside a box that's already centred and capped,
   would squeeze it to nothing on a wide screen */
.learn { --ln-max: 1180px; --ln-pad: max(20px, env(safe-area-inset-left, 0px)); }
/* Learn's buttons (the Hub's own .btn isn't on these pages): a pill, its main one filled */
.learn .btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 44px; padding: 0 18px; border-radius: 999px; border: 1px solid var(--line-strong);
  background: transparent; color: var(--text); font: 500 15px/1 var(--ui); text-decoration: none; cursor: pointer; }
.learn .btn:hover { background: var(--panel); }
.learn .btn.main { background: var(--text); color: var(--bg); border-color: var(--text); }
.learn .btn.main:hover { opacity: .9; }
.learn .btn[disabled] { opacity: .6; cursor: default; }
.learn [hidden] { display: none !important; }
.ln-page { max-width: var(--ln-max); margin: 0 auto; padding: 40px var(--ln-pad) 80px; box-sizing: border-box; }
.ln-narrow { max-width: 860px; }
.ln-page h1 { font: 400 clamp(32px, 4.6vw, 50px)/1.05 var(--head); letter-spacing: -0.03em; margin: 0 0 14px; text-wrap: balance; }
.ln-page h2 { font: 600 22px/1.2 var(--head); margin: 44px 0 14px; letter-spacing: -0.01em; }
/* a page's title, its button beside it on a wide screen and under it on a narrow one, with a gap
   below either way before the words that follow */
.ln-headrow { display: flex; align-items: flex-end; justify-content: space-between; gap: 18px 24px; flex-wrap: wrap; margin: 0 0 18px; }
.ln-headrow > div:first-child { flex: 1 1 420px; min-width: 0; }
.ln-headrow h1 { margin: 0; }
.ln-headbtn { flex: none; padding-bottom: 6px; }
.ln-head .lede { margin: 0 0 22px; }
.ln-search { max-width: 680px; }
.ln-search .search { height: 52px; border-radius: 14px; }
.ln-search .search input { font-size: 16px; }
.ln-filters { margin: 14px 0 0; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; }
.chip.on { background: var(--info-dim); border-color: var(--info); color: var(--info-ink); }
.chip.ln-warm { background: var(--key-dim); border-color: transparent; color: var(--key); }
a.chip:hover { border-color: var(--text-3); color: var(--text); }
@media (pointer: coarse) { .ln-filters .chip, .ln-side a.chip { min-height: 44px; } }
.ln-faint { color: var(--text-3); font-size: 14px; }
.ln-empty { color: var(--text-2); padding: 18px 20px; border: 1px dashed var(--line-strong); border-radius: 14px; }
.ln-results { list-style: none; margin: 0; padding: 0; display: grid; gap: 12px; }
.ln-results li { padding: 14px 16px; border: 1px solid var(--line); border-radius: 12px; background: var(--panel); }
.ln-results a { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--text); flex-wrap: wrap; }
.ln-results p { margin: 6px 0 0; color: var(--text-2); font-size: 14.5px; line-height: 1.5; overflow-wrap: anywhere; }
.ln-results b { font: 600 16px/1.3 var(--head); }
.ln-results a:hover b { text-decoration: underline; }
.ln-results .kind-chip { min-height: 0; padding: 2px 10px; font-size: 12px; cursor: inherit; }
@media (pointer: coarse) { .ln-results .kind-chip { min-height: 0; } }
.ln-found { max-width: 760px; }
.ln-back { margin: 20px 0 0; }
.ln-sechead { margin: 44px 0 16px; }
.ln-sechead h2 { margin: 0 0 4px; }
.ln-sechead p { margin: 0; max-width: 44em; }
.ln-invite b { display: block; color: var(--text); font: 600 17px/1.3 var(--head); margin: 0 0 4px; }
.ln-invite p { margin: 0; max-width: 44em; }
.ln-results mark { background: var(--accent-dim); color: var(--text); border-radius: 3px; }

/* a glow of the tutorial's own colour, when it has no picture: light through a nebula */
.ln-pic { display: block; aspect-ratio: 16 / 9; overflow: hidden; background: var(--dark-bg); }
.ln-pic img, .ln-pic canvas { display: block; width: 100%; height: 100%; object-fit: cover; }
.ln-glow, .ln-hero {
    --a: hsl(var(--hue, 260) 85% 70% / .85); --b: hsl(calc(var(--hue, 260) + 70) 80% 62% / .6); --c: hsl(calc(var(--hue, 260) + 20) 60% 22%);
    background: radial-gradient(circle at 26% 40%, var(--a) 0, transparent 34%), radial-gradient(circle at 70% 60%, var(--b) 0, transparent 32%),
                radial-gradient(circle at 50% 50%, var(--c), #07080f 78%);
}

.ln-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.ln-card, .ln-feature { display: flex; flex-direction: column; border: 1px solid var(--line); border-radius: 16px; overflow: hidden; background: var(--panel); text-decoration: none; color: var(--text); min-width: 0; }
.ln-card:hover, .ln-feature:hover { border-color: var(--line-strong); background: var(--raised); }
.ln-in { display: flex; flex-direction: column; gap: 7px; padding: 14px 16px 16px; min-width: 0; }
.ln-in b { font: 600 17px/1.3 var(--head); }
.ln-in small { color: var(--text-2); font-size: 14px; }
.ln-by { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; font-size: 13px; color: var(--text-3); }
.ln-av { width: 24px; height: 24px; border-radius: 50%; background: linear-gradient(135deg, #3fb8d6, #8f7cff); display: inline-block; flex: none; object-fit: cover; }
.ln-feature { display: grid; grid-template-columns: 1.3fr 1fr; border-radius: 20px; }
.ln-feature .ln-pic { aspect-ratio: auto; min-height: 280px; }
.ln-feature .ln-in { padding: 28px; gap: 10px; justify-content: center; }
.ln-feature .ln-in b { font-size: 26px; }
.ln-self { align-self: flex-start; }

.ln-courses { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.ln-course { border: 1px solid var(--line); border-radius: 16px; padding: 18px; background: var(--panel); min-width: 0; }
.ln-course b { font: 600 18px var(--head); }
.ln-course b a { color: var(--text); text-decoration: none; }
.ln-course > small { display: block; color: var(--text-2); }
.ln-course ol { margin: 10px 0 0; padding-left: 20px; color: var(--text-body); font-size: 14.5px; }
.ln-course li a { color: inherit; }
.ln-course li.done, .ln-course li.done a { color: var(--ok); }
.ln-course li svg { width: 14px; height: 14px; vertical-align: -2px; }
.ln-bar { height: 6px; border-radius: 3px; background: var(--line-strong); margin: 12px 0 8px; overflow: hidden; }
.ln-bar i { display: block; height: 6px; border-radius: 3px; background: var(--info); }

/* a tutorial and a course */
.ln-hero { position: relative; overflow: hidden; min-height: 340px; display: flex; align-items: flex-end; color: var(--dark-text); }
.ln-hero.ln-short { min-height: 240px; }
.ln-heroimg { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }
.ln-hero .ln-w { position: relative; }
.ln-w { width: 100%; max-width: var(--ln-max); margin: 0 auto; padding: 100px var(--ln-pad) 28px; box-sizing: border-box; background: linear-gradient(0deg, rgba(8, 8, 10, .92), transparent); }
.ln-hero h1 { font: 400 clamp(32px, 5vw, 48px)/1.05 var(--head); letter-spacing: -0.03em; margin: 8px 0 12px; text-wrap: balance; color: var(--dark-text); }
.ln-hero .crumbs, .ln-hero .crumbs a { color: #d4d4d8; }
.ln-hero .ln-by { color: var(--dark-text-body); font-size: 14px; }
.ln-hero .chip.on { color: var(--dark-text); background: rgba(138, 184, 255, .2); border-color: #8ab8ff; }
.ln-body { max-width: var(--ln-max); margin: 0 auto; padding: 28px var(--ln-pad) 80px; display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: 44px; box-sizing: border-box; }
.ln-body.ln-one { grid-template-columns: minmax(0, 860px); }
.ln-main { min-width: 0; }
.ln-article { padding: 0; max-width: none; }
.ln-article > :first-child { margin-top: 18px; }
.ln-status { padding: 12px 16px; border-radius: 12px; background: var(--info-soft); border: 1px solid var(--info-line); color: var(--info-ink); margin: 0 0 18px; }
.ln-gate { margin: 24px 0; padding: 24px; border-radius: 16px; border: 1px solid var(--line-strong); background: var(--raised); }
.ln-gate p { color: var(--text-2); }
.ln-actions { display: flex; gap: 10px; flex-wrap: wrap; margin: 30px 0 10px; }
.ln-actions .btn { min-height: 44px; padding: 0 18px; border: 1px solid var(--line-strong); color: var(--text); background: transparent; }
.ln-actions .btn.main { background: var(--text); color: var(--bg); border-color: var(--text); }
.ln-actions .btn[disabled] { opacity: .6; cursor: default; }
.ln-actions svg { width: 17px; height: 17px; }
.ln-report, .ln-say { display: grid; gap: 6px; margin: 12px 0; max-width: 620px; }
.ln-row { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; margin-top: 4px; }
.ln-f { width: 100%; box-sizing: border-box; min-height: 44px; border-radius: 10px; border: 1px solid var(--control, #6b6b72); background: var(--panel); color: var(--text); padding: 8px 12px; font: 15px/1.5 var(--ui); }
.ln-f:focus { outline: 2px solid var(--info); outline-offset: 1px; border-color: var(--info); }
textarea.ln-f { resize: vertical; }
.ln-comments { border-top: 1px solid var(--line); margin-top: 32px; padding-top: 6px; }
.ln-comments h2 { font: 600 20px var(--head); margin: 18px 0 10px; }
.ln-thread { list-style: none; margin: 14px 0 0; padding: 0; display: grid; gap: 14px; }
.ln-replies { margin: 0 0 0 36px; }
.ln-comment { display: flex; gap: 12px; }
.ln-comment p { margin: 2px 0 0; font-size: 15px; color: var(--text-body); overflow-wrap: anywhere; }
.ln-comment b { font-size: 14px; }
.ln-muted { display: block; }
.ln-muted details > summary { cursor: pointer; font-size: 14px; }
.ln-muted details[open] { display: flex; gap: 12px; flex-wrap: wrap; }
.ln-muted details[open] > summary { flex-basis: 100%; }
.ln-cact { margin-top: 2px; }
.ln-link { background: none; border: 0; padding: 0; color: var(--text-3); font: 13px var(--ui); text-decoration: underline; cursor: pointer; min-height: 24px; }
@media (pointer: coarse) { .ln-link { min-height: 44px; } }
.ln-side { min-width: 0; }
.ln-panel { border: 1px solid var(--line); border-radius: 14px; padding: 16px 18px; background: var(--panel); margin-bottom: 14px; font-size: 14.5px; overflow-wrap: anywhere; }
.ln-panel .grp { margin: 0 0 8px; }
.ln-panel p { margin: 4px 0 0; }
.ln-panel b a { color: var(--text); }

.ln-progress { margin: 0 0 18px; }
.ln-steps { list-style: none; margin: 18px 0 0; padding: 0; display: grid; gap: 12px; }
.ln-steps li { display: grid; grid-template-columns: 36px minmax(0, 1fr) auto; gap: 14px; align-items: start; padding: 16px; border: 1px solid var(--line); border-radius: 14px; background: var(--panel); }
.ln-steps li.done { border-color: var(--ok-dim); }
.ln-steps li > div { display: grid; gap: 6px; min-width: 0; }
.ln-steps a { color: var(--text); text-decoration: none; }
.ln-steps a b { font: 600 17px var(--head); }
.ln-steps small { color: var(--text-2); }
.ln-num { width: 32px; height: 32px; border-radius: 50%; border: 1px solid var(--line-strong); display: grid; place-items: center; font: 600 14px var(--ui); background: var(--raised); }
.ln-steps li.done .ln-num { background: var(--ok-dim); border-color: var(--ok); color: var(--ok); }
.ln-num svg { width: 16px; height: 16px; }
.ln-done { display: flex; align-items: center; gap: 6px; font-size: 14px; color: var(--text-2); min-height: 44px; cursor: pointer; }
.ln-done input { width: 20px; height: 20px; }

/* writing */
.ln-mine { list-style: none; margin: 20px 0 0; padding: 0; display: grid; gap: 10px; }
.ln-mine li { display: flex; align-items: center; gap: 8px 12px; flex-wrap: wrap; padding: 14px 16px; border: 1px solid var(--line); border-radius: 12px; background: var(--panel); }
.ln-mine li > a { color: var(--text); text-decoration: none; flex: 1 1 260px; min-width: 0; }
.ln-mine b { font: 600 17px var(--head); }
.ln-tool { display: flex; align-items: center; gap: 10px 12px; padding: 10px var(--m-pad, 20px); background: var(--info-dim); border-bottom: 1px solid var(--info-line); flex-wrap: wrap; color: var(--info-ink); }
.ln-tool b { color: var(--text); font-weight: 600; }
.ln-saved { font-size: 13px; color: var(--info-ink); }
.ln-sp { flex: 1; }
.btn.ln-small { min-height: 40px; padding: 0 14px; font-size: 14px; border: 1px solid var(--line-strong); color: var(--text); background: var(--panel); }
.btn.ln-small.main { background: var(--text); color: var(--bg); border-color: var(--text); }
.btn[disabled] { opacity: .55; cursor: default; }
.ln-flow { padding: 12px var(--m-pad, 20px); border-bottom: 1px solid var(--line); font-size: 13px; }
.ln-flow ol { list-style: none; margin: 0; padding: 0; display: flex; gap: 6px 8px; flex-wrap: wrap; align-items: center; }
.ln-flow li { display: flex; align-items: center; gap: 8px; }
.ln-flow li + li::before { content: "→"; color: var(--text-3); }
.ln-flow span { padding: 4px 10px; border-radius: 99px; border: 1px solid var(--line-strong); color: var(--text-2); }
.ln-flow li.on span { background: var(--info-dim); border-color: var(--info); color: var(--info-ink); }
.ln-wrap { display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 36px; max-width: 1240px; margin: 0 auto; padding: 24px var(--ln-pad) 80px; box-sizing: border-box; }
.ln-edit { min-width: 0; }
.ln-lab { display: block; font-size: 13px; color: var(--text-2); margin: 14px 0 5px; }
.ln-edit .ln-lab:first-of-type { margin-top: 0; }
.ln-titlein { font: 400 28px/1.2 var(--head); }
.ln-md { font: 14px/1.6 var(--mono); min-height: 420px; }
.ln-hint { margin: 6px 0 0; }
.ln-tabs { display: flex; gap: 4px; margin: 20px 0 10px; border-bottom: 1px solid var(--line); }
.ln-tabs button { background: none; border: 0; border-bottom: 2px solid transparent; padding: 10px 14px; min-height: 44px; color: var(--text-2); font: 600 14px var(--ui); cursor: pointer; margin-bottom: -1px; }
.ln-tabs button[aria-selected="true"] { color: var(--text); border-bottom-color: var(--info); }
.ln-tools { display: flex; gap: 4px; margin-bottom: 8px; flex-wrap: wrap; }
.ln-tools button { min-height: 36px; padding: 0 10px; border-radius: 7px; border: 1px solid var(--line-strong); background: var(--raised); color: var(--text); font: 13px var(--ui); cursor: pointer; }
@media (pointer: coarse) { .ln-tools button { min-height: 44px; } }
.ln-tools button:hover { background: var(--hover); }
.ln-preview { min-height: 300px; padding: 4px 2px; }
.ln-note { margin: 0 0 18px; display: block; }
.ln-checks { list-style: none; margin: 0; padding: 0; display: grid; gap: 6px; font-size: 14px; color: var(--text-body); }
.ln-checks li { display: flex; gap: 8px; align-items: center; }
.ln-checks li.ok { color: var(--ok); }
.ln-checks svg { width: 16px; height: 16px; flex: none; }
.ln-checks i { font-style: normal; width: 16px; text-align: center; color: var(--text-3); }
.ln-pics { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
.ln-pics li { display: grid; grid-template-columns: 48px minmax(0, 1fr) auto; gap: 10px; align-items: center; }
.ln-pics img { width: 48px; height: 48px; object-fit: cover; border-radius: 8px; border: 1px solid var(--line); background: var(--bg-2, var(--panel)); }
.ln-pics span { font-size: 13.5px; color: var(--text-body); }
.ln-pics small { display: block; color: var(--text-3); font-size: 12.5px; }
.ln-check { display: flex; gap: 10px; align-items: flex-start; font-size: 14px; color: var(--text-body); margin: 16px 0 4px; cursor: pointer; }
.ln-check input { width: 20px; height: 20px; margin: 1px 0 0; flex: none; }
.ln-chiprow { margin-top: 8px; }
.ln-chiprow:empty { display: none; }

@media (max-width: 980px) {
    .ln-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .ln-body, .ln-wrap { grid-template-columns: minmax(0, 1fr); gap: 24px; }
}
@media (max-width: 760px) {
    .ln-page { padding-top: 28px; }
    .ln-grid, .ln-courses, .ln-feature { grid-template-columns: minmax(0, 1fr); }
    .ln-feature .ln-pic { min-height: 0; aspect-ratio: 16 / 9; }
    .ln-feature .ln-in { padding: 18px; }
    .ln-feature .ln-in b { font-size: 21px; }
    .ln-hero { min-height: 260px; }
    .ln-w { padding-top: 70px; }
    .ln-steps li { grid-template-columns: 32px minmax(0, 1fr); }
    .ln-steps .ln-done { grid-column: 2; }
    .ln-replies { margin-left: 18px; }
    .ln-headbtn { padding-bottom: 0; }
    .ln-tool .ln-sp { flex-basis: 100%; height: 0; }
    .ln-titlein { font-size: 22px; }
}