/* =========================================================================
   Articles, long-form pages, playable examples and engraved notation.
   ========================================================================= */
@layer page {

/* ---------------------------------------------------------- article header */
.article-hero { padding-block: clamp(1.6rem, 4vw, 3rem) clamp(1.6rem, 3.5vw, 2.6rem); background: var(--tint); border-bottom: 1px solid var(--tint-line); position: relative; overflow: clip; }
.article-hero-grid { display: grid; gap: 2rem; align-items: center; }
.article-hero .crumbs { margin-bottom: 1.2rem; }
.article-head h1 { font-size: clamp(2rem, 1.1rem + 3.6vw, 3.6rem); max-width: 22ch; }
.article-dek { margin-top: 1rem; max-width: 46ch; font-family: var(--font-text); font-size: var(--fs-lead); line-height: 1.5; color: var(--ink-2); text-wrap: pretty; }
.article-meta { margin-top: 1.4rem; display: flex; flex-wrap: wrap; align-items: center; gap: .5rem 1.1rem; font-size: .875rem; color: var(--ink-2); font-weight: 560; }
.article-meta a { text-decoration: none; }
.article-meta .chip { background: var(--surface); }
.article-art { display: none; aspect-ratio: 16 / 9; border-radius: var(--radius-lg); overflow: hidden; background: var(--tint-2); color: var(--art-ink); border: 1px solid var(--tint-line); }
.article-art svg { width: 100%; height: 100%; }
@media (min-width: 56rem) { .article-hero-grid { grid-template-columns: minmax(0, 1.25fr) minmax(0, .85fr); gap: 3rem; } .article-art { display: block; } }

/* ---------------------------------------------------------------- layout */
.article-layout { display: grid; gap: 2.5rem; padding-block: clamp(2rem, 5vw, 4rem); }
.page-body .article-layout, .article-layout.is-page { padding-block: clamp(2rem, 5vw, 3.5rem); }
@media (min-width: 64rem) {
  .article-layout { grid-template-columns: minmax(0, var(--measure)) 17.5rem; justify-content: center; gap: clamp(2.5rem, 5vw, 5rem); }
  .aside-col { position: sticky; top: calc(var(--head-h) + 1.5rem); align-self: start; max-height: calc(100dvh - var(--head-h) - 3rem); overflow-y: auto; overscroll-behavior: contain; scrollbar-width: thin; padding-bottom: 1rem; }
}

/* ----------------------------------------------------------------- prose */
.prose { font-family: var(--font-text); font-size: var(--fs-prose); line-height: 1.72; color: var(--ink); min-width: 0; font-variant-numeric: lining-nums; hanging-punctuation: first; }
.prose > * + * { margin-top: 1.25em; }
.prose p { text-wrap: pretty; }
.prose h2 { margin-top: 2.6em; font-size: clamp(1.55rem, 1.2rem + 1.4vw, 2.1rem); position: relative; }
.prose h3 { margin-top: 2em; font-size: clamp(1.2rem, 1.05rem + .6vw, 1.45rem); }
.prose h4 { margin-top: 1.6em; }
.prose h2 + *, .prose h3 + * { margin-top: .7em; }
.prose strong { font-weight: 650; }
.prose em { font-style: italic; }
.prose a { color: var(--accent); text-decoration-color: color-mix(in oklab, var(--accent) 38%, transparent); text-decoration-thickness: .08em; transition: text-decoration-color var(--t-fast); }
.prose a:hover { text-decoration-color: currentColor; }
.h-anchor { position: absolute; left: -1.5ch; top: 0; width: 1.5ch; font-family: var(--font-ui); font-weight: 600; font-size: .7em; color: var(--ink-3); text-decoration: none; opacity: 0; transition: opacity var(--t-fast); }
.prose h2:hover .h-anchor, .prose h3:hover .h-anchor, .h-anchor:focus-visible { opacity: 1; }
@media (max-width: 52rem) { .h-anchor { display: none; } }

.prose ul, .prose ol { padding-left: 0; list-style: none; display: grid; gap: .55em; }
.prose ul > li { position: relative; padding-left: 1.5em; }
.prose ul > li::before { content: ""; position: absolute; left: .15em; top: .72em; width: .62em; height: .44em; border-radius: 50%; background: var(--fill); rotate: -22deg; }
.prose ol { counter-reset: n; }
.prose ol > li { position: relative; padding-left: 2.1em; counter-increment: n; }
.prose ol > li::before { content: counter(n); position: absolute; left: 0; top: .1em; width: 1.5em; height: 1.5em; display: grid; place-items: center; border-radius: 50%; background: var(--tint-2); color: var(--accent); font: 650 .78em/1 var(--font-ui); font-variant-numeric: tabular-nums; }
.prose li > ul, .prose li > ol { margin-top: .5em; }
.prose blockquote { padding: 1.1em 1.4em; border-left: 4px solid var(--fill); border-radius: 0 var(--radius) var(--radius) 0; background: var(--tint); font-size: .96em; }
.prose blockquote > * + * { margin-top: .7em; }
.prose hr { margin-block: 2.5em; }
.prose code { padding: .12em .4em; border-radius: 6px; background: var(--surface-2); border: 1px solid var(--line); font-size: .84em; }
.prose pre { overflow-x: auto; padding: 1.1rem 1.3rem; border-radius: var(--radius); background: var(--surface-2); border: 1px solid var(--line); font-size: .86rem; line-height: 1.55; tab-size: 4; -webkit-overflow-scrolling: touch; }
.prose pre code { padding: 0; border: 0; background: none; font-size: inherit; white-space: pre; }
.prose .table-wrap { font-size: .94rem; }
.prose img { border-radius: var(--radius); }
.prose .lead { font-size: var(--fs-lead); }

/* ------------------------------------------------------- playable examples */
.ex { margin-block: 1.9em; border: 1px solid var(--line); border-radius: var(--radius-lg); background: var(--surface); overflow: hidden; font-family: var(--font-ui); transition: border-color var(--t-med), box-shadow var(--t-med); }
.ex.is-playing { border-color: var(--tint-line); box-shadow: 0 10px 40px -18px color-mix(in oklab, var(--fill) 60%, transparent); }
.ex-staff { padding: 1.15rem 1.3rem .75rem; overflow-x: auto; scrollbar-width: thin; }
.ex-bar { display: flex; align-items: center; gap: .85rem; padding: .6rem .75rem .6rem .8rem; border-top: 1px solid var(--line); background: color-mix(in oklab, var(--surface-2) 72%, var(--surface)); }
.ex-names { margin-left: auto; min-width: 0; font-size: .8125rem; font-weight: 520; color: var(--ink-3); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-variant-numeric: tabular-nums; }
.ex-cap { font-size: .875rem; font-weight: 600; color: var(--ink-2); }

.ex-play {
  display: inline-flex; align-items: center; gap: .55em; min-height: 2.5rem; padding: .3em 1.15em .3em .85em; border-radius: var(--radius-pill);
  background: var(--fill); color: var(--on-fill); font-family: var(--font-ui); font-size: .9rem; font-weight: 680; line-height: 1; cursor: pointer; flex: none;
  transition: transform var(--t-med) var(--spring), background var(--t-fast), box-shadow var(--t-med); -webkit-tap-highlight-color: transparent; position: relative;
}
.ex-play .ico { width: 1.05em; height: 1.05em; }
.ex-play .ico-stop { display: none; }
.ex-play:hover { transform: translateY(-1px); box-shadow: 0 8px 20px -10px color-mix(in oklab, var(--fill) 80%, transparent); }
.ex-play:active { transform: scale(.95); transition-duration: 60ms; }
.ex-play.is-playing .ico-play { display: none; }
.ex-play.is-playing .ico-stop { display: block; }
.ex-play.is-playing { background: var(--ink); color: var(--paper); }
.ex-play.is-loading { pointer-events: none; opacity: .7; }
.ex-play.is-loading .ico { animation: spin .8s linear infinite; }
@keyframes spin { to { rotate: 360deg; } }

/* The inline version: a quiet pill that sits in a sentence. */
.ex-inline { min-height: 0; padding: .12em .7em .12em .45em; font-size: .84em; line-height: 1.35; background: var(--tint-2); color: var(--accent); vertical-align: .06em; gap: .4em; font-weight: 650; box-shadow: inset 0 0 0 1px var(--tint-line); }
.ex-inline:hover { background: var(--fill); color: var(--on-fill); box-shadow: none; }
.ex-inline.is-playing { background: var(--ink); color: var(--paper); box-shadow: none; }
.ex-inline .ico { width: .9em; height: .9em; }

/* ------------------------------------------------------- engraved notation */
.score { display: block; height: auto; max-width: 100%; min-width: calc(var(--w, 40) * 6.2px); margin-inline: auto; color: var(--ink); overflow: visible; }
.score .staff, .score .barline { fill: none; stroke: var(--staff-line); stroke-width: .13; }
.score .ledger { fill: none; stroke: var(--ink); stroke-width: .16; }
.score .stem { fill: none; stroke: currentColor; stroke-width: .12; }
.score use, .score .beam { fill: currentColor; }
.score .nh { transition: fill var(--t-fast); }
.score-colour .nh { fill: var(--pitch); }
.score .nt { transform-box: fill-box; transform-origin: center; transition: transform .26s var(--spring), opacity var(--t-med); }
.score .nt.is-on { transform: translateY(-.28px) scale(1.1); }
.score .nt.is-on .nh { fill: var(--pitch); }
.score .nt.is-on .stem { stroke: var(--pitch); }
.ex.is-playing .nt.is-done { opacity: .5; }
.score .playhead { fill: var(--fill); opacity: 0; transition: opacity var(--t-med); pointer-events: none; }
.score .playhead.is-on { opacity: .85; }
.score .tup text, .score .tup use { fill: currentColor; }

/* ---------------------------------------------------------------- contents */
.toc { padding: 0 0 1.4rem; font-family: var(--font-ui); }
.toc h2 { font-family: var(--font-ui); font-size: .8125rem; font-weight: 650; letter-spacing: 0; color: var(--ink-3); margin-bottom: .7rem; }
.toc ol { list-style: none; padding: 0; display: grid; gap: 0; border-left: 1px solid var(--line); }
.toc a { display: block; padding: .42rem 0 .42rem 1rem; margin-left: -1px; border-left: 2px solid transparent; font-size: .9rem; line-height: 1.35; font-weight: 520; color: var(--ink-2); text-decoration: none; transition: color var(--t-fast), border-color var(--t-fast), padding var(--t-med) var(--spring); }
.toc a:hover { color: var(--ink); }
.toc a[aria-current] { color: var(--accent); border-left-color: var(--fill); font-weight: 650; padding-left: 1.2rem; }
.toc-mobile { margin-bottom: 1.6rem; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); font-family: var(--font-ui); }
.toc-mobile summary { display: flex; align-items: center; justify-content: space-between; padding: .85rem 1.1rem; font-weight: 650; font-size: .95rem; list-style: none; }
.toc-mobile summary::-webkit-details-marker { display: none; }
.toc-mobile summary .ico { transition: transform var(--t-med) var(--spring); }
.toc-mobile[open] summary .ico { transform: rotate(180deg); }
.toc-mobile .toc { padding: 0 1.1rem 1rem; }
@media (min-width: 64rem) { .toc-mobile { display: none; } }
@media (max-width: 63.99rem) { .aside-col > .toc { display: none; } }

/* ------------------------------------------------------------------- aside */
.aside-block { padding-block: 1.3rem; border-top: 1px solid var(--line); font-family: var(--font-ui); }
.aside-block h2 { font-family: var(--font-ui); font-size: .8125rem; font-weight: 650; letter-spacing: 0; color: var(--ink-3); margin-bottom: .75rem; }
.aside-list { list-style: none; padding: 0; display: grid; gap: .15rem; }
.aside-list a { display: flex; flex-direction: column; gap: .1rem; padding: .45rem .6rem; margin-inline: -.6rem; border-radius: 10px; color: var(--ink); font-size: .93rem; font-weight: 580; line-height: 1.3; text-decoration: none; transition: background var(--t-fast); }
.aside-list a:hover { background: var(--tint); color: var(--accent); }
.aside-dek { font-size: .8rem; font-weight: 450; color: var(--ink-3); }
.aside-note { font-size: .85rem; color: var(--ink-3); margin-top: .6rem; }

/* --------------------------------------------------------------------- FAQ */
.faq { margin-top: 3em; }
.faq h2 { margin-bottom: 1rem; }
.faq details { border-top: 1px solid var(--line); font-family: var(--font-ui); }
.faq details:last-of-type { border-bottom: 1px solid var(--line); }
.faq summary { display: flex; align-items: center; justify-content: space-between; gap: 1.2rem; padding: 1.05rem .2rem; font-weight: 650; font-size: 1.05rem; line-height: 1.35; list-style: none; color: var(--ink); }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: ""; flex: none; width: .65rem; height: .65rem; border-right: 2px solid var(--ink-2); border-bottom: 2px solid var(--ink-2); rotate: 45deg; margin-right: .3rem; transition: rotate var(--t-med) var(--spring); }
.faq details[open] summary::after { rotate: -135deg; }
.faq summary:hover { color: var(--accent); }
.faq details > p { padding: 0 .2rem 1.3rem; font-family: var(--font-text); font-size: 1.02rem; line-height: 1.65; color: var(--ink-2); max-width: 62ch; }
@supports (interpolate-size: allow-keywords) {
  .faq details { interpolate-size: allow-keywords; }
  .faq details::details-content { block-size: 0; overflow: clip; transition: block-size var(--t-med) var(--ease-out), content-visibility var(--t-med) allow-discrete; }
  .faq details[open]::details-content { block-size: auto; }
}

/* ----------------------------------------------------- end of article furniture */
.author-box { margin-top: 3.2em; padding: 1.3rem 1.4rem; border: 1px solid var(--line); border-radius: var(--radius-lg); background: var(--surface-2); font-family: var(--font-ui); font-size: .93rem; line-height: 1.6; color: var(--ink-2); }
.author-box > * + * { margin-top: .6rem; }
.author-box .label { font-size: .8125rem; font-weight: 650; color: var(--ink-3); }
.author-box a { color: var(--accent); }
.readout { font-size: .84rem; color: var(--ink-3); overflow-wrap: anywhere; }
.prevnext { display: grid; gap: .9rem; margin-top: 2.2em; font-family: var(--font-ui); }
.prevnext a { display: grid; gap: .25rem; padding: 1.1rem 1.3rem; border: 1px solid var(--line); border-radius: var(--radius-lg); background: var(--surface); text-decoration: none; color: var(--ink); transition: border-color var(--t-fast), transform var(--t-med) var(--ease-out), background var(--t-fast); }
.prevnext a:hover { border-color: var(--tint-line); background: var(--tint); transform: translateY(-2px); }
.prevnext span { font-size: .8125rem; font-weight: 650; color: var(--accent); }
.prevnext strong { font-family: var(--font-display); font-size: 1.1rem; line-height: 1.25; letter-spacing: -.01em; }
.prevnext .pn-next { text-align: right; }
@media (min-width: 40rem) { .prevnext { grid-template-columns: 1fr 1fr; } }

.book-note { margin-top: 2.2em; padding-top: 1.1rem; border-top: 1px solid var(--line); font-family: var(--font-ui); font-size: .9rem; color: var(--ink-2); line-height: 1.55; }
.book-note-kicker { display: block; font-size: .8125rem; font-weight: 650; color: var(--ink-3); margin-bottom: .25rem; }
.book-note-text { display: block; font-family: var(--font-text); font-size: .98rem; }
.book-note-links { display: flex; flex-wrap: wrap; gap: .3rem .6rem; margin-top: .5rem; font-weight: 620; }
.book-note-links a { color: var(--accent); }

/* ---------------------------------------------------------------- page heads */
.page-head { padding-block: clamp(2rem, 5vw, 4rem) clamp(1.4rem, 3vw, 2.4rem); background: var(--tint); border-bottom: 1px solid var(--tint-line); }
.page-head .crumbs { margin-bottom: 1.1rem; }
.page-head h1 { max-width: 20ch; }
.page-dek { margin-top: 1rem; max-width: 52ch; font-family: var(--font-text); font-size: var(--fs-lead); line-height: 1.5; color: var(--ink-2); }
.meta-row { margin-top: 1.1rem; display: flex; flex-wrap: wrap; gap: .4rem 1.2rem; list-style: none; padding: 0; font-size: .875rem; color: var(--ink-3); font-weight: 520; }
.label { font-size: .8125rem; font-weight: 650; color: var(--accent); }
}

/* ---- glossary links: quiet until hovered ------------------------------------ */
.prose a.gl { color: inherit; text-decoration: underline dotted var(--ink-3); text-decoration-thickness: 1.5px; text-underline-offset: .22em; }
.prose a.gl:hover, .prose a.gl:focus-visible { color: var(--fill-ink, var(--fill)); text-decoration-style: solid; }