/* The B2B Shelf · Field Book
   Paper, ink and one survey orange. 8px grid. Hairlines, no shadows. Radius 0 to 2px. */

@font-face { font-family: "Newsreader"; src: url(../fonts/news-400.woff2) format("woff2"); font-weight: 400; font-style: normal; font-display: swap; }
@font-face { font-family: "Newsreader"; src: url(../fonts/news-500.woff2) format("woff2"); font-weight: 500 600; font-style: normal; font-display: swap; }
@font-face { font-family: "Newsreader"; src: url(../fonts/news-i400.woff2) format("woff2"); font-weight: 400; font-style: italic; font-display: swap; }
@font-face { font-family: "Public Sans"; src: url(../fonts/pub-400.woff2) format("woff2"); font-weight: 400; font-display: swap; }
@font-face { font-family: "Public Sans"; src: url(../fonts/pub-500.woff2) format("woff2"); font-weight: 500; font-display: swap; }
@font-face { font-family: "Public Sans"; src: url(../fonts/pub-600.woff2) format("woff2"); font-weight: 600 700; font-display: swap; }
@font-face { font-family: "IBM Plex Mono"; src: url(../fonts/mono-400.woff2) format("woff2"); font-weight: 400; font-display: swap; }
@font-face { font-family: "IBM Plex Mono"; src: url(../fonts/mono-500.woff2) format("woff2"); font-weight: 500 700; font-display: swap; }

:root {
	--paper: #F4F1E8;
	--ink: #16181D;
	--graphite: #5C6068;
	--grid: #DAD4C5;
	--orange: #E4572E;
	--wash: #FBE4DA;
	--blue: #2E5A87;
	--olive: #5F6E3B;
	--ochre: #B07F2C;
	--serif: "Newsreader", Georgia, "Times New Roman", serif;
	--sans: "Public Sans", "Helvetica Neue", Arial, sans-serif;
	--mono: "IBM Plex Mono", ui-monospace, Menlo, Consolas, monospace;
	--u: 8px;
	--gutter: 24px;
	--margin: 64px;
	--max: 1200px;
	--grid-size: 24px;
	--hair: 1px solid var(--grid);
	--rule: 1px solid var(--ink);
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
	margin: 0;
	background: var(--paper);
	color: var(--ink);
	font: 400 18px/28px var(--serif);
	font-variant-numeric: lining-nums;
	-webkit-font-smoothing: antialiased;
	text-rendering: optimizeLegibility;
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; }
p { margin: 0 0 16px; }
h1, h2, h3, h4 { margin: 0; font-weight: 500; }
button, input, select, textarea { font: inherit; color: inherit; }
:focus-visible { outline: 2px solid var(--blue); outline-offset: 2px; }
::selection { background: var(--wash); }
[hidden] { display: none !important; }

.skip { position: absolute; left: -9999px; top: 0; background: var(--ink); color: var(--paper); padding: 8px 16px; z-index: 10; font: 500 15px var(--sans); }
.skip:focus { left: 16px; top: 16px; }

.wrap { max-width: calc(var(--max) + 2 * var(--margin)); margin: 0 auto; padding: 0 var(--margin); }

/* ---------- type helpers ---------- */
.coord, .tag, .label {
	font: 500 12px/16px var(--mono);
	letter-spacing: .06em;
	text-transform: uppercase;
	color: var(--graphite);
	margin: 0 0 16px;
}
.tag { display: inline-block; margin: 0; }
.mono { font-family: var(--mono); }
.muted { color: var(--graphite); font-size: 16px; line-height: 24px; }
.lead { font: 400 20px/30px var(--serif); max-width: 66ch; color: var(--ink); }
.section__title { font: 500 30px/36px var(--serif); letter-spacing: -.005em; margin-bottom: 24px; }
.page__title { font: 500 40px/46px var(--serif); letter-spacing: -.01em; margin-bottom: 16px; max-width: 22ch; }

/* Underlines that draw in on hover, 150ms. */
.link, .prose a, .changelog__text a, .muted a, .signup__note a, .site-footer a, .crumbs a {
	text-decoration: none;
	background: linear-gradient(currentColor, currentColor) 0 100% / 0 1px no-repeat;
	transition: background-size 150ms ease;
	padding-bottom: 1px;
}
.link { background-size: 100% 1px; }
.link:hover, .prose a:hover, .changelog__text a:hover, .muted a:hover, .signup__note a:hover, .site-footer a:hover, .crumbs a:hover { background-size: 100% 1px; }
.prose a, .changelog__text a { color: var(--blue); background-size: 100% 1px; }

.chip { display: inline-block; width: 8px; height: 8px; background: var(--chip, var(--ink)); margin-right: 8px; vertical-align: 1px; }

/* ---------- buttons ---------- */
.btn, .button, button.button, input.button, .single_add_to_cart_button, #place_order, .checkout-button, .woocommerce-button {
	display: inline-flex;
	align-items: center;
	justify-content: center;
	min-height: 48px;
	padding: 0 24px;
	border-radius: 2px;
	border: 1px solid var(--ink);
	background: var(--ink);
	color: var(--paper);
	font: 500 15px/22px var(--sans);
	text-decoration: none;
	cursor: pointer;
	transition: background-color 150ms ease, color 150ms ease;
	white-space: nowrap;
}
.btn:hover, .button:hover, .single_add_to_cart_button:hover, #place_order:hover, .checkout-button:hover { background: #2a2d34; }
.btn--secondary, .button.alt-secondary, .woocommerce-message .button, .woocommerce-info .button {
	background: transparent;
	color: var(--ink);
}
.btn--secondary:hover, .woocommerce-message .button:hover, .woocommerce-info .button:hover { background: var(--ink); color: var(--paper); }
/* The one signal action on a page: Buy and Place order. */
button.single_add_to_cart_button, .single_add_to_cart_button, button#place_order, #place_order, a.checkout-button, .checkout-button { background: var(--orange); border-color: var(--orange); color: #16181D; }
button.single_add_to_cart_button:hover, button#place_order:hover, a.checkout-button:hover { background: #cf4a23; border-color: #cf4a23; color: #16181D; }
.button:disabled, .button.disabled { opacity: .5; cursor: not-allowed; }

/* ---------- grid background, ticks ---------- */
.grid-bg {
	background-image:
		linear-gradient(to right, rgba(218, 212, 197, .5) 1px, transparent 1px),
		linear-gradient(to bottom, rgba(218, 212, 197, .5) 1px, transparent 1px);
	background-size: var(--grid-size) var(--grid-size);
	background-position: -1px -1px;
}
.ticks { position: relative; }
.ticks::before, .ticks::after {
	content: "";
	position: absolute;
	width: 12px;
	height: 12px;
	pointer-events: none;
}
.ticks::before { top: -8px; left: -8px; border-top: 1px solid var(--ink); border-left: 1px solid var(--ink); }
.ticks::after { bottom: -8px; right: -8px; border-bottom: 1px solid var(--ink); border-right: 1px solid var(--ink); }

/* ---------- header ---------- */
.site-header { border-bottom: var(--hair); background: var(--paper); position: relative; z-index: 5; }
.site-header__inner { display: flex; align-items: center; justify-content: space-between; min-height: 80px; gap: 24px; }
.brand { display: block; color: var(--ink); line-height: 0; }
.brand svg { height: 26px; width: auto; }
.nav { display: flex; align-items: center; gap: 32px; }
.nav__toggle { display: none; }
.nav__list { list-style: none; display: flex; gap: 32px; margin: 0; padding: 0; }
.nav__list a, .header-cart {
	font: 400 15px/22px var(--sans);
	text-decoration: none;
	background: linear-gradient(currentColor, currentColor) 0 100% / 0 1px no-repeat;
	transition: background-size 150ms ease;
	padding-bottom: 2px;
}
.nav__list a:hover, .nav__list .current-menu-item > a, .nav__list .current_page_item > a, .header-cart:hover { background-size: 100% 1px; }
.header-cart { display: inline-flex; gap: 8px; align-items: center; }
.header-cart__n { font: 500 12px/16px var(--mono); border: 1px solid var(--ink); min-width: 22px; height: 22px; display: inline-grid; place-items: center; padding: 0 4px; border-radius: 2px; }
.header-cart.is-empty .header-cart__n { border-color: var(--grid); color: var(--graphite); }

/* ---------- footer ---------- */
.site-footer { border-top: var(--rule); margin-top: 96px; padding: 48px 0 32px; font: 400 15px/22px var(--sans); }
.site-footer__inner { display: grid; grid-template-columns: 1.2fr 1fr 1fr; gap: var(--gutter); }
.site-footer__brand svg { height: 22px; width: auto; color: var(--ink); }
.site-footer__line { margin-top: 16px; color: var(--graphite); }
.site-footer__company p { margin: 0 0 8px; color: var(--graphite); }
.footer-list { list-style: none; margin: 0; padding: 0; columns: 2; column-gap: var(--gutter); }
.footer-list li { margin-bottom: 8px; break-inside: avoid; }
.footer-list a { text-decoration: none; }
.site-footer__base { display: flex; justify-content: space-between; gap: 16px; margin-top: 40px; padding-top: 16px; border-top: var(--hair); }

/* ---------- sections ---------- */
.section { padding: 96px 0 0; }
.site-main > .section:first-child { padding-top: 0; }

/* Hero */
.hero { border-bottom: var(--hair); overflow-x: clip; }
.hero__inner { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: var(--gutter); align-items: center; min-height: 600px; padding-top: 72px; padding-bottom: 72px; }
.hero__copy { grid-column: 1 / span 6; }
.hero__title { font: 500 56px/60px var(--serif); letter-spacing: -.01em; margin-bottom: 24px; max-width: 12ch; }
.hero__line { font: 400 20px/30px var(--sans); color: var(--graphite); max-width: 34ch; margin-bottom: 32px; }
.hero__actions { display: flex; flex-wrap: wrap; gap: 16px; margin-bottom: 32px; }
.hero__note { font: 400 12px/16px var(--mono); letter-spacing: .02em; color: var(--graphite); max-width: 40ch; }
.hero__covers { grid-column: 7 / span 6; position: relative; height: 480px; }
.hero__cover { position: absolute; width: 41%; display: block; transition: transform 150ms ease; }

.hero__cover .cover { border: var(--hair); width: 100%; background: var(--paper); }
.hero__cover--1 { left: 0; top: 64px; z-index: 1; }
.hero__cover--2 { left: 19%; top: 16px; z-index: 2; }
.hero__cover--3 { left: 38%; top: 80px; z-index: 3; }
.hero__cover--4 { left: 57%; top: 32px; z-index: 4; }
.leader { position: absolute; display: block; pointer-events: none; }
.leader::before { content: ""; position: absolute; width: 5px; height: 5px; background: var(--ink); border-radius: 50%; }
.leader::after { content: ""; position: absolute; background: var(--ink); }
.leader__label { position: absolute; white-space: nowrap; font: 500 11px/14px var(--mono); letter-spacing: .06em; color: var(--ink); background: var(--paper); padding: 0 4px; }
/* Each leader runs from a dot on its cover to a label outside the stack. */
.leader--1 { left: 12%; bottom: -6px; }
.leader--1::before { left: -2px; top: -2px; }
.leader--1::after { left: 0; top: 0; width: 1px; height: 40px; }
.leader--1 .leader__label { left: -4px; top: 44px; }
.leader--2 { left: 30%; top: -2px; }
.leader--2::before { left: -2px; top: -2px; }
.leader--2::after { left: 0; width: 1px; height: 24px; top: -22px; }
.leader--2 .leader__label { left: -4px; top: -42px; }
.leader--3 { left: 70%; bottom: -2px; }
.leader--3::before { left: -2px; top: -2px; }
.leader--3::after { left: 0; top: 0; width: 1px; height: 28px; }
.leader--3 .leader__label { left: -4px; top: 32px; }
.leader--4 { left: 72%; top: -2px; }
.leader--4::before { left: -2px; top: -2px; }
.leader--4::after { left: 0; width: 1px; height: 24px; top: -22px; }
.leader--4 .leader__label { right: -4px; top: -42px; }

/* Method strip */
.made__cols { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--gutter); border-top: var(--rule); }
.made__col { padding: 24px 24px 0 0; }
.made__col + .made__col { border-left: var(--hair); padding-left: 24px; }
.made__col h3 { font: 600 22px/28px var(--sans); margin: 16px 0 8px; }
.made__col p { font: 400 17px/26px var(--serif); color: var(--ink); max-width: 34ch; }
.b2b-icon { width: 48px; height: 48px; color: var(--ink); }
.made__more { margin-top: 24px; font: 400 15px/22px var(--sans); }

/* Shelves */
.shelf { margin-bottom: 64px; }
.shelf__head { display: flex; justify-content: space-between; align-items: baseline; margin-bottom: 24px; gap: 16px; }
.shelf__tag { font: 500 12px/16px var(--mono); letter-spacing: .06em; display: inline-flex; align-items: center; gap: 8px; }
.shelf__tag::before { content: ""; width: 24px; height: 8px; background: var(--chip); }
.shelf__all { font: 400 15px/22px var(--sans); }
.shelf__books { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 48px var(--gutter); }
.shelf__line { height: 8px; border-top: 2px solid var(--ink); margin-top: 24px; }

/* Book card */
.book-card { display: flex; flex-direction: column; }
.book-card__link { text-decoration: none; display: block; }
.book-card__cover { max-width: 280px; }
.book-card__cover .cover { border: var(--hair); width: 100%; transition: transform 150ms ease; }
.book-card__link:hover .cover { transform: translateY(-4px); }
.book-card__coord { font: 500 12px/16px var(--mono); letter-spacing: .06em; text-transform: uppercase; color: var(--graphite); margin: 16px 0 8px; }
.book-card__title { font: 500 22px/28px var(--serif); margin: 0 0 8px; max-width: 18ch; }
.book-card__link:hover .book-card__title { text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 3px; }
.book-card__meta { font: 400 15px/22px var(--sans); display: flex; flex-wrap: wrap; gap: 4px 16px; align-items: baseline; margin: 0; }
.book-card__pages { color: var(--graphite); font-size: 14px; }
.book-card.is-soon .cover { opacity: .78; }
.price { font: 500 15px/22px var(--sans); }
.price del { color: var(--graphite); }
.price ins { text-decoration: none; }
.price--soon { display: inline-flex; gap: 8px; align-items: baseline; }
.price__planned { color: var(--graphite); font-weight: 400; }
.soon-tag { font: 500 11px/16px var(--mono); letter-spacing: .06em; text-transform: uppercase; border: 1px solid var(--ink); padding: 1px 6px; border-radius: 2px; white-space: nowrap; }
.soon-note { font: 400 15px/22px var(--sans); color: var(--graphite); margin: 8px 0 16px; }

/* Measured callout */
.standard__inner { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: var(--gutter); align-items: start; }
.standard__copy { grid-column: 1 / span 5; }
.standard__copy p { font-size: 18px; }
.measured { grid-column: 7 / span 6; background: var(--wash); border-left: 3px solid var(--orange); padding: 24px 32px 24px 28px; margin: 0; }
.measured .label { color: var(--ink); margin-bottom: 8px; display: block; }
.measured__num { font: 500 48px/52px var(--mono); margin-bottom: 12px; }
.measured__text { font: 400 20px/30px var(--serif); max-width: 36ch; }
.measured__src { font: 400 12px/18px var(--mono); color: var(--graphite); margin: 0; }

/* Bundle offer */
.bundle-offer__inner { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: var(--gutter); border: var(--hair); padding: 48px; margin: 0 var(--margin); max-width: var(--max); }
@media (min-width: 1329px) { .bundle-offer__inner { margin: 0 auto; } }
.bundle-offer__inner > div:first-child { grid-column: 1 / span 7; }
.bundle-offer__price { grid-column: 9 / span 4; }
.big-price { font: 500 40px/46px var(--mono); margin: 0 0 8px; }
.big-price .muted { font: 400 15px/22px var(--sans); }

/* FAQ */
.faq__inner { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: var(--gutter); }
.faq__inner > div:first-child { grid-column: 1 / span 4; }
.faq__list { grid-column: 5 / span 8; border-top: var(--rule); }
.faq__item { border-bottom: var(--hair); }
.faq__item summary { cursor: pointer; list-style: none; padding: 20px 40px 20px 0; position: relative; font: 600 18px/26px var(--sans); }
.faq__item summary::-webkit-details-marker { display: none; }
.faq__item summary::after { content: "+"; position: absolute; right: 0; top: 18px; font: 400 22px/28px var(--mono); }
.faq__item[open] summary::after { content: "−"; }
.faq__item p { max-width: 62ch; padding-bottom: 8px; }

/* ---------- pages ---------- */
.site-main .page { padding-top: 64px; }
.page__head { margin-bottom: 48px; }
.prose { max-width: 70ch; }
.prose h2 { font: 500 30px/36px var(--serif); margin: 48px 0 16px; }
.prose h3 { font: 600 22px/28px var(--sans); margin: 32px 0 8px; }
.prose ul, .prose ol { padding-left: 24px; margin: 0 0 16px; }
.prose li { margin-bottom: 8px; }
.prose ul li::marker { content: "–  "; color: var(--graphite); }
.prose ol li::marker { font: 500 14px var(--mono); color: var(--graphite); }
.prose strong { font-weight: 600; }
.prose blockquote { border-left: 1px solid var(--ink); margin: 24px 0; padding-left: 24px; font-style: italic; }
.prose table { border-collapse: collapse; width: 100%; font: 400 15px/22px var(--sans); margin: 24px 0; }
.prose th { font-weight: 600; text-align: left; border-top: var(--rule); border-bottom: var(--rule); padding: 8px 8px 8px 0; }
.prose td { border-bottom: var(--hair); padding: 8px 8px 8px 0; }
.plain-list { list-style: none; padding: 0; }
.plain-list li { border-bottom: var(--hair); padding: 12px 0; display: flex; justify-content: space-between; gap: 16px; }

/* Crumbs */
.crumbs { font: 500 12px/16px var(--mono); letter-spacing: .06em; text-transform: uppercase; color: var(--graphite); margin: 0 0 32px; display: flex; gap: 8px; flex-wrap: wrap; }
.crumbs a { text-decoration: none; }

/* ---------- library ---------- */
.tabs { display: flex; flex-wrap: wrap; gap: 0; border-bottom: var(--rule); margin-bottom: 48px; }
.tabs__tab { font: 500 15px/22px var(--sans); text-decoration: none; padding: 12px 20px; border: 1px solid transparent; border-bottom: 0; margin-bottom: -1px; display: inline-flex; align-items: center; border-radius: 2px 2px 0 0; color: var(--graphite); }
.tabs__tab:hover { color: var(--ink); }
.tabs__tab.is-active { border-color: var(--ink); background: var(--paper); color: var(--ink); border-bottom: 1px solid var(--paper); }
.library__grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 56px var(--gutter); }
.library__bundles { margin-top: 72px; border-top: var(--hair); padding-top: 24px; display: flex; justify-content: space-between; align-items: center; gap: 24px; flex-wrap: wrap; font: 400 17px/26px var(--sans); }
.library__bundles p { margin: 0; }

/* ---------- book page ---------- */
.book { padding-top: 48px; }
.book__top { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: var(--gutter); align-items: start; }
.book__cover { grid-column: 1 / span 5; }
.book__cover .cover { border: var(--hair); width: 100%; }
.book__summary { grid-column: 7 / span 6; }
.book__title { font: 500 40px/46px var(--serif); letter-spacing: -.01em; margin-bottom: 16px; }
.book__subtitle { font: 400 20px/30px var(--sans); color: var(--graphite); margin-bottom: 32px; max-width: 40ch; }
.book__buy { border-top: var(--rule); border-bottom: var(--hair); padding: 24px 0; margin-bottom: 24px; }
.book__price { font: 500 32px/40px var(--mono); margin: 0 0 16px; }
.book__price .price { font: inherit; }
.book__buy form.cart { display: flex; gap: 16px; align-items: center; margin-bottom: 16px; }
.book__buy .quantity { display: none; }
.format-line { font: 500 12px/16px var(--mono); letter-spacing: .06em; text-transform: uppercase; color: var(--ink); margin: 0 0 8px; }
.book__refund { font: 400 14px/20px var(--sans); color: var(--graphite); margin: 0; }
.book__excerpt p { font-size: 18px; }
.book__section { margin-top: 96px; max-width: 960px; }
.cover-stack { position: relative; height: 0; padding-bottom: 120%; }
.cover-stack .cover { position: absolute; width: 62%; border: var(--hair); }
.cover-stack .cover:nth-child(1) { left: 0; top: 8%; }
.cover-stack .cover:nth-child(2) { left: 19%; top: 0; }
.cover-stack .cover:nth-child(3) { left: 38%; top: 12%; }

.toc { list-style: none; margin: 0; padding: 0; border-top: var(--rule); }
.toc__row { display: grid; grid-template-columns: 64px 1fr 64px; gap: 16px; border-bottom: var(--hair); padding: 12px 0; align-items: baseline; }
.toc__n, .toc__p { font: 500 14px/20px var(--mono); color: var(--graphite); }
.toc__p { text-align: right; font-weight: 400; }
.toc__t { font: 400 18px/26px var(--serif); }
.toc__row--matter .toc__t { color: var(--graphite); font-style: italic; }

.inside { list-style: none; margin: 0; padding: 0; border-top: var(--rule); }
.inside__row { display: grid; grid-template-columns: minmax(0, 300px) 120px 1fr; gap: 16px; padding: 14px 0; border-bottom: var(--hair); align-items: baseline; }
.inside__file { font: 500 14px/20px var(--mono); word-break: break-word; }
.inside__type { font: 500 11px/16px var(--mono); letter-spacing: .06em; color: var(--graphite); }
.inside__desc { font: 400 16px/24px var(--serif); }

.sources { border: var(--rule); padding: 40px 48px; background: var(--paper); }
.sources p { max-width: 64ch; }
.sources__list { list-style: none; margin: 24px 0; padding: 0; }
.sources__list li { display: grid; grid-template-columns: 48px 1fr; gap: 8px; padding: 12px 0; border-top: var(--hair); }
.sources__n { font: 500 14px/24px var(--mono); color: var(--orange); }
.sources__org { display: block; font: 600 15px/22px var(--sans); }
.sources__body .link { font: 400 17px/26px var(--serif); color: var(--blue); }

.samples { display: grid; grid-template-columns: 1fr 1fr; gap: 0; border: var(--hair); max-width: 960px; }
.sample { width: 100%; }
.samples .sample + .sample { border-left: var(--hair); }

.upsell__grid { display: grid; grid-template-columns: 1fr 1fr; gap: var(--gutter); }
.upsell__card { display: flex; flex-direction: column; gap: 8px; border: var(--hair); padding: 24px; text-decoration: none; transition: border-color 150ms ease; }
.upsell__card:hover { border-color: var(--ink); }
.upsell__card .coord { margin: 0; }
.upsell__title { font: 500 22px/28px var(--serif); }
.upsell__price { font: 500 18px/26px var(--mono); }
.upsell__price .muted { font: 400 14px var(--sans); }
.upsell__card .soon-tag { align-self: flex-start; }

/* ---------- bundles page ---------- */
.table-scroll { overflow-x: auto; margin-bottom: 64px; }
.compare { width: 100%; border-collapse: collapse; font: 400 16px/24px var(--sans); min-width: 560px; }
.compare th, .compare td { text-align: left; padding: 14px 16px 14px 0; border-bottom: var(--hair); vertical-align: top; }
.compare thead th { font-weight: 600; border-top: var(--rule); border-bottom: var(--rule); }
.compare tbody th { font-weight: 600; width: 28%; }
.compare tr.hl td, .compare tr.hl th { background: var(--wash); }
.compare td.mono { font: 500 16px/24px var(--mono); }
.bundle-card { border: var(--hair); padding: 32px; }
.bundle-card h2 { font: 500 30px/36px var(--serif); margin-bottom: 8px; }
.bundle-card h3 { font: 500 22px/28px var(--serif); margin-bottom: 16px; }
.bundle-card--library { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: var(--gutter); margin-bottom: 96px; border-color: var(--ink); }
.bundle-card__covers { grid-column: 1 / span 6; display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: 8px; align-content: start; }
.bundle-card__covers .cover { border: var(--hair); }
.bundle-card__body { grid-column: 8 / span 5; }
.bundle-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--gutter); }
.bundle-card__list { list-style: none; padding: 0; margin: 0 0 24px; font: 400 16px/24px var(--sans); }
.bundle-card__list li { padding: 8px 0; border-bottom: var(--hair); display: flex; justify-content: space-between; gap: 8px; align-items: baseline; }
.bundle-card__list .link { background-size: 0 1px; }
.bundle-card__list .link:hover { background-size: 100% 1px; }

/* ---------- changelog ---------- */
.changelog { list-style: none; margin: 0 0 48px; padding: 0; border-top: var(--rule); max-width: 880px; }
.changelog__item { display: grid; grid-template-columns: 140px 1fr; gap: var(--gutter); padding: 24px 0; border-bottom: var(--hair); }
.changelog__date { font: 500 14px/24px var(--mono); }
.changelog__tags { display: flex; gap: 8px; margin: 0 0 8px; }
.changelog__tags .tag { border: 1px solid var(--grid); padding: 0 6px; color: var(--ink); }
.changelog__title { font: 500 22px/28px var(--serif); margin-bottom: 8px; }
.changelog__text p { margin-bottom: 8px; }
.changelog--compact .changelog__item { padding: 12px 0; font: 400 16px/24px var(--sans); }

/* ---------- free chapter ---------- */
.free { border-bottom: var(--hair); }
.free__inner { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: var(--gutter); padding-top: 72px; padding-bottom: 96px; align-items: start; }
.free__cover { grid-column: 1 / span 4; }
.free__cover .cover { border: var(--hair); width: 100%; background: var(--paper); }
.free__copy { grid-column: 6 / span 7; background: var(--paper); padding: 8px 0; }
.ticks-list { list-style: none; padding: 0; margin: 0 0 32px; font: 400 16px/24px var(--sans); }
.ticks-list li { padding: 8px 0 8px 24px; border-bottom: var(--hair); position: relative; }
.ticks-list li::before { content: ""; position: absolute; left: 0; top: 16px; width: 10px; height: 6px; border-left: 1px solid var(--ink); border-bottom: 1px solid var(--ink); }

/* ---------- signup forms ---------- */
.signup { margin: 8px 0 0; max-width: 560px; }
.signup__label { display: block; font: 500 12px/16px var(--mono); letter-spacing: .06em; text-transform: uppercase; margin-bottom: 8px; }
.signup__row { display: flex; gap: 8px; }
.signup__input, .store input[type="text"], .store input[type="email"], .store input[type="tel"], .store input[type="password"], .store input[type="number"], .store select, .store textarea, .store .select2-selection {
	min-height: 48px;
	border: 1px solid var(--ink);
	border-radius: 2px;
	background: #fff;
	padding: 0 14px;
	font: 400 16px/22px var(--sans);
	width: 100%;
}
.store textarea { padding: 12px 14px; min-height: 96px; }
.signup__input:focus, .store input:focus, .store select:focus, .store textarea:focus { outline: 2px solid var(--blue); outline-offset: 1px; }
.signup__note { font: 400 13px/20px var(--sans); color: var(--graphite); margin: 8px 0 0; }
.signup__ok { background: var(--wash); border-left: 3px solid var(--orange); padding: 16px 20px; font: 400 16px/24px var(--sans); }
.signup__err { border: 1px solid var(--ink); padding: 12px 16px; font: 400 15px/22px var(--sans); }
.hp { position: absolute !important; left: -9999px !important; width: 1px; height: 1px; overflow: hidden; }

/* ---------- WooCommerce: notices ---------- */
.woocommerce-notices-wrapper:empty { display: none; }
.woocommerce-message, .woocommerce-info, .woocommerce-error, .woocommerce-NoticeGroup .woocommerce-error {
	list-style: none;
	margin: 0 0 32px;
	padding: 16px 20px;
	border: 1px solid var(--ink);
	border-radius: 2px;
	font: 400 16px/24px var(--sans);
	display: flex;
	flex-wrap: wrap;
	gap: 12px 16px;
	align-items: center;
	background: var(--paper);
}
.woocommerce-message { border-left: 3px solid var(--orange); }
.woocommerce-error li { list-style: none; }
.woocommerce-message .button, .woocommerce-info .button { order: 2; min-height: 40px; }
.woocommerce-message .btn { order: 2; min-height: 40px; }

/* ---------- WooCommerce: cart ---------- */
.page--store .page__title { max-width: none; }
.store .shop_table { width: 100%; border-collapse: collapse; font: 400 16px/24px var(--sans); margin-bottom: 32px; }
.store .shop_table th { font-weight: 600; text-align: left; border-top: var(--rule); border-bottom: var(--rule); padding: 12px 12px 12px 0; }
.store .shop_table td { border-bottom: var(--hair); padding: 16px 12px 16px 0; vertical-align: middle; }
.store .shop_table .product-thumbnail img { width: 64px; border: var(--hair); }
.store .shop_table .product-remove a { text-decoration: none; font: 400 22px/1 var(--mono); color: var(--graphite); }
.store .shop_table .product-name a { font: 500 18px/26px var(--serif); text-decoration: none; }
.store .shop_table .product-quantity { display: none; }
.store .coupon { display: flex; gap: 8px; align-items: center; }
.store .coupon label { position: absolute; left: -9999px; }
.store .coupon input { max-width: 220px; }
.store .actions { text-align: right; }
.store button[name="update_cart"] { display: none; }
.store .cart-collaterals { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: var(--gutter); }
.store .cart_totals { grid-column: 7 / span 6; }
.store .cart_totals h2, .store h3, .woocommerce-billing-fields h3, #order_review_heading { font: 500 22px/28px var(--serif); margin: 0 0 16px; }
.store .wc-proceed-to-checkout { margin-top: 16px; }
.store .wc-proceed-to-checkout .checkout-button { width: 100%; }
.store .cart-empty { font: 400 18px/28px var(--serif); }
.store .return-to-shop .button { background: transparent; color: var(--ink); }

/* ---------- WooCommerce: checkout ---------- */
.store form.checkout { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: 0 var(--gutter); }
.store form.checkout > .woocommerce-NoticeGroup { grid-column: 1 / -1; }
.store #customer_details { grid-column: 1 / span 6; grid-row: 1 / span 3; }
.store #order_review_heading { grid-column: 8 / span 5; grid-row: 1; }
.store #order_review { grid-column: 8 / span 5; grid-row: 2; align-self: start; }
.store #order_review_heading { align-self: end; }
.store .col2-set .col-1, .store .col2-set .col-2 { width: 100%; }
.store .form-row { margin: 0 0 16px; display: flex; flex-direction: column; gap: 6px; }
.store .form-row label { font: 500 14px/20px var(--sans); }
.store .form-row .required { color: var(--orange); text-decoration: none; border: 0; }
.store .form-row .optional { color: var(--graphite); font-weight: 400; }
.store .woocommerce-input-wrapper { display: block; }
.store .form-row-first, .store .form-row-last { width: 100%; }
@media (min-width: 720px) {
	.store .woocommerce-billing-fields__field-wrapper { display: grid; grid-template-columns: 1fr 1fr; gap: 0 16px; }
	.store .woocommerce-billing-fields__field-wrapper .form-row-wide { grid-column: 1 / -1; }
}
.store #payment { border: var(--rule); padding: 24px; margin-top: 16px; font: 400 15px/22px var(--sans); }
.store #payment ul.payment_methods { list-style: none; margin: 0 0 16px; padding: 0; }
.store #payment .payment_box { background: var(--wash); padding: 12px 16px; margin-top: 8px; }
.store #place_order { width: 100%; margin-top: 16px; }
.store .woocommerce-terms-and-conditions-wrapper { font-size: 14px; line-height: 20px; }
.store .woocommerce-privacy-policy-text p { font-size: 14px; line-height: 20px; color: var(--graphite); }
.store .woocommerce-form-login-toggle, .store .woocommerce-form-coupon-toggle { margin-bottom: 0; }
.store .checkout_coupon, .store .woocommerce-form-login { border: var(--hair); padding: 24px; margin-bottom: 32px; }
.store .select2-container .select2-selection--single { height: 48px; border: 1px solid var(--ink); border-radius: 2px; }
.store .select2-container .select2-selection--single .select2-selection__rendered { line-height: 46px; padding-left: 14px; }
.store .select2-container .select2-selection--single .select2-selection__arrow { height: 46px; }

/* ---------- WooCommerce: account, order received ---------- */
.store .woocommerce-MyAccount-navigation ul { list-style: none; padding: 0; margin: 0 0 32px; display: flex; flex-wrap: wrap; gap: 0; border-bottom: var(--rule); }
.store .woocommerce-MyAccount-navigation a { display: block; padding: 10px 16px; text-decoration: none; font: 500 15px/22px var(--sans); color: var(--graphite); }
.store .woocommerce-MyAccount-navigation .is-active a { color: var(--ink); border: 1px solid var(--ink); border-bottom-color: var(--paper); margin-bottom: -1px; background: var(--paper); }
.store .woocommerce-MyAccount-content { font: 400 16px/24px var(--sans); }
.store .woocommerce-order-overview { list-style: none; padding: 0; display: flex; flex-wrap: wrap; gap: 0; border-top: var(--rule); border-bottom: var(--hair); margin: 0 0 32px; }
.store .woocommerce-order-overview li { padding: 16px 24px 16px 0; margin-right: 24px; font: 400 13px/20px var(--mono); text-transform: uppercase; letter-spacing: .04em; color: var(--graphite); }
.store .woocommerce-order-overview li strong { display: block; font: 500 16px/24px var(--sans); color: var(--ink); text-transform: none; letter-spacing: 0; }
.store .woocommerce-thankyou-order-received { font: 500 22px/28px var(--serif); }
.store .woocommerce-order-downloads { border: var(--rule); padding: 24px; margin-bottom: 32px; background: var(--wash); }
.store .woocommerce-table--order-downloads .download-file a { background: var(--ink); color: var(--paper); }
.store .woocommerce-order-downloads, .store .woocommerce-MyAccount-content { min-width: 0; }
.store .woocommerce-table--order-downloads { display: block; overflow-x: auto; }
.store td .button, .store .download-file a { white-space: normal; text-align: left; line-height: 20px; padding-top: 10px; padding-bottom: 10px; }
.store .woocommerce-customer-details address { font-style: normal; border: var(--hair); padding: 16px; }
.store .woocommerce-form-login, .store .woocommerce-form-register { max-width: 480px; }
.store fieldset { border: var(--hair); padding: 16px; margin: 0 0 16px; }
.store .woocommerce-Addresses { display: grid; gap: var(--gutter); grid-template-columns: 1fr 1fr; }
.store .wc-block-components-notice-banner { border: 1px solid var(--ink); padding: 16px; font: 400 16px/24px var(--sans); }


/* ---------- consultations ---------- */
.call__inner { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: var(--gutter); align-items: start; border-top: var(--rule); padding-top: 32px; }
.call__copy { grid-column: 1 / span 5; }
.call__copy p { max-width: 40ch; }
.call__inner .steps { grid-column: 7 / span 6; }
.steps { list-style: none; margin: 0; padding: 0; }
.steps__item { display: grid; grid-template-columns: 56px 1fr; column-gap: 16px; padding: 16px 0; border-bottom: var(--hair); }
.steps__item:first-child { border-top: var(--hair); }
.steps__n { grid-row: span 2; font: 500 14px/24px var(--mono); color: var(--graphite); }
.steps__t { font: 600 17px/24px var(--sans); }
.steps__d { font: 400 16px/24px var(--serif); color: var(--ink); }
.call--book .steps { max-width: 720px; margin: 16px 0 24px; }
.book__call { font: 400 15px/22px var(--sans); margin: 0 0 8px; padding: 10px 12px; border-left: 1px solid var(--ink); }
.book__call strong { font-weight: 600; }
.consults { border: var(--rule); padding: 32px; margin: 0 0 48px; background: var(--paper); }
.consults__title { font: 500 30px/36px var(--serif); margin-bottom: 12px; }
.consults__intro { font: 400 17px/26px var(--serif); max-width: 66ch; }
.consults__list { list-style: none; padding: 0; margin: 16px 0; border-top: var(--rule); }
.consults__row { display: grid; grid-template-columns: 1fr auto auto auto; gap: 8px 24px; align-items: center; padding: 14px 0; border-bottom: var(--hair); font: 400 15px/22px var(--sans); }
.consults__book { font: 500 17px/24px var(--serif); }
.consults__code { font: 500 13px/20px var(--mono); letter-spacing: .04em; }
.consults__status { color: var(--graphite); font-size: 14px; }
.consults__btn { min-height: 40px; }
.consults__note { font: 400 14px/20px var(--sans); color: var(--graphite); margin: 0; }
@media (max-width: 900px) {
	.call__inner { grid-template-columns: 1fr; }
	.call__copy, .call__inner .steps { grid-column: 1 / -1; }
	.consults__row { grid-template-columns: 1fr; gap: 4px; }
	.consults__btn { justify-self: start; margin-top: 8px; }
}
@media (max-width: 720px) { .consults { padding: 20px; } }

/* ---------- responsive ---------- */
@media (max-width: 1100px) {
	:root { --margin: 40px; }
	.library__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
	.hero__title { font-size: 48px; line-height: 52px; }
}
@media (max-width: 900px) {
	.hero__inner, .standard__inner, .faq__inner, .book__top, .free__inner, .bundle-card--library, .bundle-offer__inner, .store .cart-collaterals, .store form.checkout { grid-template-columns: 1fr; }
	.hero__copy, .hero__covers, .standard__copy, .measured, .faq__inner > div:first-child, .faq__list, .book__cover, .book__summary, .free__cover, .free__copy, .bundle-card__covers, .bundle-card__body, .bundle-offer__inner > div, .bundle-offer__price, .store .cart_totals, .store #customer_details, .store #order_review_heading, .store #order_review { grid-column: 1 / -1; grid-row: auto; }
	.hero__covers { height: 420px; max-width: 560px; }
	.book__cover { max-width: 380px; }
	.free__cover { max-width: 260px; }
	.shelf__books { grid-template-columns: repeat(2, minmax(0, 1fr)); }
	.made__cols { grid-template-columns: 1fr; }
	.made__col + .made__col { border-left: 0; padding-left: 0; border-top: var(--hair); }
	.site-footer__inner { grid-template-columns: 1fr 1fr; }
	.site-footer__brand { grid-column: 1 / -1; }
	.bundle-grid, .upsell__grid { grid-template-columns: 1fr; }
	.inside__row { grid-template-columns: 1fr; gap: 4px; }
}
@media (max-width: 720px) {
	:root { --margin: 16px; --grid-size: 16px; --gutter: 16px; }
	body { font-size: 17px; line-height: 26px; }
	.site-header__inner { min-height: 64px; }
	.brand svg { height: 20px; }
	.nav { gap: 16px; }
	.nav__desktop { display: none; }
	.nav__toggle { display: block; }
	.nav__toggle > summary { display: block; list-style: none; cursor: pointer; font: 500 15px/22px var(--sans); border: 1px solid var(--ink); border-radius: 2px; padding: 6px 12px; }
	.nav__toggle > summary::-webkit-details-marker { display: none; }
	.nav__toggle[open] .nav__list { display: flex; flex-direction: column; gap: 0; position: absolute; left: 0; right: 0; top: 100%; background: var(--paper); border-bottom: var(--rule); padding: 8px var(--margin) 16px; }
	.nav__toggle[open] .nav__list a { display: block; padding: 12px 0; border-bottom: var(--hair); font-size: 17px; }
	.hero__inner { min-height: 0; padding-top: 48px; padding-bottom: 56px; }
	.hero__title { font-size: 40px; line-height: 44px; }
	.hero__line { font-size: 18px; line-height: 28px; }
	.hero__actions .btn { flex: 1 1 100%; }
	.hero__covers { height: 300px; margin-top: 16px; }
	.leader__label { font-size: 10px; }
	.section { padding-top: 72px; }
	.section__title { font-size: 26px; line-height: 32px; }
	.page__title, .book__title { font-size: 32px; line-height: 38px; }
	.library__grid, .shelf__books { grid-template-columns: 1fr; }
	.book-card__cover { max-width: 240px; }
	.measured { padding: 20px; }
	.measured__num { font-size: 36px; line-height: 40px; }
	.bundle-offer__inner { padding: 24px; margin: 0 var(--margin); }
	.sources { padding: 24px; }
	.samples { grid-template-columns: 1fr; }
	.samples .sample + .sample { border-left: 0; border-top: var(--hair); }
	.changelog__item { grid-template-columns: 1fr; gap: 4px; }
	.signup__row { flex-direction: column; }
	.site-footer__inner { grid-template-columns: 1fr; }
	.site-footer__base { flex-direction: column; }
	.toc__row { grid-template-columns: 40px 1fr 40px; }
	.store .shop_table_responsive thead { display: none; }
	.store .shop_table_responsive tr { display: block; border-bottom: var(--hair); padding: 8px 0; }
	.store .shop_table_responsive td { display: flex; justify-content: space-between; border: 0; padding: 6px 0; }
	.store .shop_table_responsive td::before { content: attr(data-title); font-weight: 600; }
	.store .shop_table_responsive td.product-remove::before, .store .shop_table_responsive td.product-thumbnail::before, .store .shop_table_responsive td.actions::before { content: none; }
	.store .woocommerce-Addresses { grid-template-columns: 1fr; }
}
@media (prefers-reduced-motion: reduce) {
	* { transition: none !important; }
}
@media print {
	.site-header, .site-footer, .hero__actions { display: none; }
	body { background: #fff; }
}

/* =====================================================================
   Navigation, motion and polish (1.2.0)
   Motion is gated by html.js and prefers-reduced-motion: the page is
   complete at rest, and nothing waits on JavaScript to be readable.
   ===================================================================== */
:root {
	--ease-out: cubic-bezier(.2, .7, .1, 1);
	--ease-in-out: cubic-bezier(.65, 0, .35, 1);
	--hdr: 80px;
	--hdr-on: 1;
	--secnav: 0px;
}
@media (max-width: 720px) { :root { --hdr: 64px; } }

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--hdr) * var(--hdr-on) + var(--secnav) + 16px); }

.screen-reader-text { border: 0; clip: rect(1px, 1px, 1px, 1px); clip-path: inset(50%); height: 1px; margin: -1px; overflow: hidden; padding: 0; position: absolute !important; width: 1px; word-wrap: normal !important; }
.screen-reader-text:focus { clip: auto; clip-path: none; height: auto; width: auto; z-index: 100; background: var(--paper); padding: 8px 12px; }

/* ---------- sticky header that tucks away ---------- */
.site-header { position: sticky; top: 0; z-index: 30; transition: transform 320ms var(--ease-out), border-color 200ms ease; will-change: transform; }
html.header-hidden .site-header { transform: translateY(-100%); }
html.is-scrolled .site-header { border-bottom-color: var(--ink); }
.readbar { position: absolute; left: 0; right: 0; bottom: -1px; height: 2px; background: var(--ink); transform-origin: 0 50%; transform: scaleX(var(--read, 0)); pointer-events: none; }

/* Larger hit areas in navigation (WCAG 2.5.5). */
.nav__list a, .header-cart { min-height: 44px; display: inline-flex; align-items: center; }
.footer-list a { display: inline-block; padding: 6px 0; }
.nav__list a { background-position: 0 calc(100% - 11px); }

/* ---------- book page: section navigation ---------- */
.secnav { position: sticky; top: calc(var(--hdr) * var(--hdr-on)); z-index: 20; margin: 72px 0 0; transition: top 320ms var(--ease-out); }
.secnav::before { content: ""; position: absolute; inset: 0 calc(50% - 50vw); background: var(--paper); border-bottom: var(--hair); z-index: -1; }
.secnav__inner { display: flex; align-items: center; gap: 24px; min-height: 52px; overflow-x: auto; scrollbar-width: none; }
.secnav__inner::-webkit-scrollbar { display: none; }
.secnav__label { font: 500 12px/16px var(--mono); letter-spacing: .06em; color: var(--graphite); white-space: nowrap; padding-right: 16px; border-right: var(--hair); }
.secnav__list { list-style: none; display: flex; gap: 4px; margin: 0; padding: 0; }
.secnav__link { position: relative; display: inline-flex; align-items: center; min-height: 44px; padding: 0 12px; font: 500 14px/20px var(--sans); color: var(--graphite); text-decoration: none; white-space: nowrap; transition: color 150ms ease; }
.secnav__link::after { content: ""; position: absolute; left: 12px; right: 12px; bottom: 0; height: 2px; background: var(--ink); transform: scaleX(0); transform-origin: 0 50%; transition: transform 260ms var(--ease-out); }
.secnav__link:hover { color: var(--ink); }
.secnav__link.is-current { color: var(--ink); }
.secnav__link.is-current::after { transform: scaleX(1); }
.book .book__section:first-of-type { margin-top: 64px; }

/* ---------- sticky buy bar ---------- */
.buybar { position: fixed; left: 0; right: 0; bottom: 0; z-index: 40; background: var(--paper); border-top: var(--rule); transform: translateY(110%); transition: transform 360ms var(--ease-out); padding-bottom: env(safe-area-inset-bottom, 0px); }
.buybar.is-on { transform: translateY(0); }
.buybar__inner { max-width: calc(var(--max) + 2 * var(--margin)); margin: 0 auto; padding: 10px var(--margin); display: flex; align-items: center; gap: 16px; }
.buybar__thumb { width: 32px; flex: none; }
.buybar__thumb .cover { border: var(--hair); width: 32px; height: auto; }
.buybar__text { display: flex; flex-direction: column; min-width: 0; flex: 1; }
.buybar__coord { font: 500 11px/14px var(--mono); letter-spacing: .06em; color: var(--graphite); }
.buybar__title { font: 500 17px/22px var(--serif); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.buybar__price { font: 500 18px/24px var(--mono); white-space: nowrap; }
.buybar__btn { min-height: 44px; }
.btn--signal { background: var(--orange); border-color: var(--orange); color: #16181D; }
.btn--signal:hover { background: #cf4a23; border-color: #cf4a23; }
.single-product .site-footer { padding-bottom: 104px; }
@media (max-width: 720px) {
	.buybar__inner { gap: 12px; }
	.buybar__coord { display: none; }
	.buybar__title { font-size: 15px; }
	.buybar__price { font-size: 16px; }
	.buybar__btn { padding: 0 14px; }
}

/* ---------- small, precise interactions ---------- */
.btn, .button, .single_add_to_cart_button, #place_order, .checkout-button { transition: background-color 150ms ease, color 150ms ease, border-color 150ms ease, transform 120ms ease; }
.btn:active, .button:active, .single_add_to_cart_button:active, #place_order:active { transform: translateY(1px); }
.made__more .link::after, .shelf__all::after, .standard__copy .link::after, .library__bundles .btn::after, .hero__actions .btn--primary::after {
	content: "→"; display: inline-block; margin-left: 8px; transition: transform 200ms var(--ease-out);
}
.made__more .link:hover::after, .shelf__all:hover::after, .standard__copy .link:hover::after, .library__bundles .btn:hover::after, .hero__actions .btn--primary:hover::after { transform: translateX(4px); }
.book-card__cover .cover, .hero__cover .cover { transition: transform 360ms var(--ease-out), border-color 200ms ease; }
.book-card__link:hover .cover { transform: translateY(-6px); border-color: var(--ink); }
.book-card__coord { transition: color 200ms ease; }
.book-card__link:hover .book-card__coord { color: var(--ink); }
.hero__cover:hover { z-index: 10; }
.hero__cover:hover .cover { transform: translateY(-8px); border-color: var(--ink); }
.upsell__card, .bundle-card { transition: border-color 200ms ease, transform 300ms var(--ease-out); }
.upsell__card:hover { transform: translateY(-2px); }
.sources__list li { transition: background-color 200ms ease; }
.sources__list li:hover { background: rgba(218, 212, 197, .35); }
.sources__n { color: var(--ink); position: relative; }
.sources__n::before { content: ""; position: absolute; left: -12px; top: 9px; width: 0; height: 0; border-top: 4px solid transparent; border-bottom: 4px solid transparent; border-left: 6px solid var(--orange); opacity: 0; transform: translateX(-4px); transition: opacity 200ms ease, transform 200ms var(--ease-out); }
.sources__list li:hover .sources__n::before { opacity: 1; transform: translateX(0); }
.faq__item summary::after { transition: transform 260ms var(--ease-out); }
.faq__item[open] summary::after { content: "+"; transform: rotate(45deg); }
.faq__item summary:hover { color: var(--blue); }

/* FAQ: smooth height where the browser supports it. */
@supports (interpolate-size: allow-keywords) {
	:root { interpolate-size: allow-keywords; }
	.faq__item::details-content { height: 0; overflow: clip; transition: height 320ms var(--ease-out), content-visibility 320ms allow-discrete; }
	.faq__item[open]::details-content { height: auto; }
}

/* Library: sliding tab indicator, animated filtering. */
.tabs { position: relative; }
.tabs__tab { border: 0 !important; background: none !important; margin-bottom: 0; min-height: 44px; transition: color 150ms ease; }
.tabs__tab.is-active { color: var(--ink); }
.tabs__ind { position: absolute; bottom: -1px; height: 2px; background: var(--ink); left: 0; width: 0; transition: left 320ms var(--ease-out), width 320ms var(--ease-out); }
html:not(.js) .tabs__tab.is-active { box-shadow: inset 0 -2px 0 var(--ink); }
.library__item { transition: opacity 220ms ease, transform 320ms var(--ease-out); }
.library__item.is-leaving { opacity: 0; transform: translateY(8px) scale(.98); }

/* Mobile menu sheet. */
@media (max-width: 720px) {
	.nav__toggle[open] .nav__list { animation: sheet-in 260ms var(--ease-out) both; }
	.nav__toggle > summary { transition: background-color 150ms ease, color 150ms ease; min-height: 40px; display: inline-flex; align-items: center; }
	.nav__toggle[open] > summary { background: var(--ink); color: var(--paper); }
}
@keyframes sheet-in { from { opacity: 0; transform: translateY(-8px); } to { opacity: 1; transform: none; } }

/* ---------- page transitions (cross-document View Transitions) ---------- */
@view-transition { navigation: auto; }
::view-transition-old(root) { animation: 180ms ease both vt-out; }
::view-transition-new(root) { animation: 360ms var(--ease-out) both vt-in; }
::view-transition-group(*) { animation-duration: 420ms; animation-timing-function: var(--ease-out); }
@keyframes vt-out { to { opacity: 0; } }
@keyframes vt-in { from { opacity: 0; transform: translateY(10px); } }

/* ---------- entrance and scroll reveals ---------- */
html.js .reveal { opacity: 0; transform: translateY(18px); transition: opacity 700ms var(--ease-out), transform 800ms var(--ease-out); transition-delay: calc(var(--i, 0) * 70ms); }
html.js .reveal.is-in { opacity: 1; transform: none; }
html.js .shelf__line.reveal { opacity: 1; transform: scaleX(0); transform-origin: 0 50%; transition: transform 1100ms var(--ease-in-out); }
html.js .shelf__line.reveal.is-in { transform: scaleX(1); }

/* Home hero: covers deal out from a stack, leader lines draw, labels settle. */
html.js .hero__copy > * { animation: rise 800ms var(--ease-out) both; }
html.js .hero__copy > :nth-child(2) { animation-delay: 80ms; }
html.js .hero__copy > :nth-child(3) { animation-delay: 160ms; }
html.js .hero__copy > :nth-child(4) { animation-delay: 240ms; }
html.js .hero__copy > :nth-child(5) { animation-delay: 320ms; }
html.js .hero__cover { animation: deal 1100ms var(--ease-out) both; }
html.js .hero__cover--1 { --dx: 120%; --rot: -4deg; animation-delay: 250ms; }
html.js .hero__cover--2 { --dx: 70%; --rot: -2deg; animation-delay: 340ms; }
html.js .hero__cover--3 { --dx: 20%; --rot: 2deg; animation-delay: 430ms; }
html.js .hero__cover--4 { --dx: -30%; --rot: 4deg; animation-delay: 520ms; }
html.js .leader::after { animation: draw-y 500ms var(--ease-out) both; animation-delay: 1250ms; transform-origin: 50% 0; }
html.js .leader--2::after, html.js .leader--4::after { transform-origin: 50% 100%; }
html.js .leader::before, html.js .leader__label { animation: fade 400ms ease both; animation-delay: 1500ms; }
html.js .hero__covers.ticks::before, html.js .hero__covers.ticks::after { animation: tick 700ms var(--ease-out) both; animation-delay: 1100ms; }
.hero__cover { transform: translate(var(--px, 0px), var(--py, 0px)); transition: transform 600ms var(--ease-out); }
@keyframes rise { from { opacity: 0; transform: translateY(16px); } }
@keyframes deal { from { opacity: 0; transform: translateX(var(--dx)) translateY(24px) rotate(var(--rot)); } }
@keyframes draw-y { from { transform: scaleY(0); } }
@keyframes fade { from { opacity: 0; } }
@keyframes tick { from { opacity: 0; transform: scale(.4); } }

/* Book page: the cover settles in, the summary rises. */
html.js .book__cover .cover { animation: rise 900ms var(--ease-out) both; }
html.js .book__summary > * { animation: rise 800ms var(--ease-out) both; }
html.js .book__summary > :nth-child(2) { animation-delay: 70ms; }
html.js .book__summary > :nth-child(3) { animation-delay: 140ms; }
html.js .book__summary > :nth-child(4) { animation-delay: 210ms; }
html.js .book__summary > :nth-child(5) { animation-delay: 280ms; }
html.js .page__head > * { animation: rise 700ms var(--ease-out) both; }
html.js .page__head > :nth-child(2) { animation-delay: 70ms; }
html.js .page__head > :nth-child(3) { animation-delay: 140ms; }

/* Measured figure: the orange rule draws as the number settles. */
.measured { position: relative; }
html.js .measured.reveal { border-left-color: transparent; }
html.js .measured.reveal::before { content: ""; position: absolute; left: -3px; top: 0; bottom: 0; width: 3px; background: var(--orange); transform: scaleY(0); transform-origin: 50% 0; transition: transform 900ms var(--ease-in-out) 200ms; }
html.js .measured.reveal.is-in::before { transform: scaleY(1); }
.measured__num { font-variant-numeric: tabular-nums; }

/* ---------- reduced motion: everything still, nothing hidden ---------- */
@media (prefers-reduced-motion: reduce) {
	html { scroll-behavior: auto; }
	@view-transition { navigation: none; }
	html.js .reveal, html.js .shelf__line.reveal { opacity: 1 !important; transform: none !important; transition: none !important; }
	html.js .hero__copy > *, html.js .hero__cover, html.js .leader::after, html.js .leader::before, html.js .leader__label, html.js .book__cover .cover, html.js .book__summary > *, html.js .page__head > *, html.js .hero__covers.ticks::before, html.js .hero__covers.ticks::after { animation: none !important; }
	html.js .measured.reveal { border-left-color: var(--orange); }
	html.js .measured.reveal::before { display: none; }
	.site-header, .secnav, .buybar, .library__item, .tabs__ind { transition: none !important; }
}
.book__section[tabindex="-1"]:focus { outline: none; }