/*
Theme Name: DIY SEO Playbook
Theme URI: https://diyseoplaybook.com/
Author: Denny Cartwright / KSJ Growth
Author URI: https://ksjgrowth.com/
Description: A modern, accessible showcase theme for The Small Business DIY SEO Playbook.
Version: 1.0.3
Requires at least: 6.0
Tested up to: 6.8
Requires PHP: 7.4
Text Domain: diyseo-playbook
*/

:root {
	--night: #040a14;
	--navy: #07182d;
	--navy-2: #0b2340;
	--ink: #0c1725;
	--slate: #42566d;
	--muted: #6a7d91;
	--line: #d9e1e8;
	--mist: #eef3f7;
	--paper: #fbfaf7;
	--white: #ffffff;
	--blue: #35adf4;
	--blue-bright: #51c4ff;
	--gold: #f0ba36;
	--gold-soft: #ffcf58;
	--radius-sm: 10px;
	--radius: 18px;
	--radius-lg: 28px;
	--shadow: 0 24px 70px rgba(3, 17, 31, 0.13);
	--shell: 1180px;
	--header-height: 84px;
}

*,
*::before,
*::after {
	box-sizing: border-box;
}

html {
	scroll-behavior: smooth;
}

body {
	margin: 0;
	background: var(--paper);
	color: var(--ink);
	font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
	font-size: 17px;
	line-height: 1.65;
	text-rendering: optimizeLegibility;
}

body.menu-open {
	overflow: hidden;
}

img {
	display: block;
	max-width: 100%;
	height: auto;
}

figure,
blockquote,
p,
h1,
h2,
h3,
h4 {
	margin-top: 0;
}

a {
	color: inherit;
}

button,
input,
textarea,
select {
	font: inherit;
}

::selection {
	background: var(--gold);
	color: var(--night);
}

.site-shell {
	width: min(calc(100% - 44px), var(--shell));
	margin-inline: auto;
}

.screen-reader-text,
.skip-link:not(:focus) {
	position: absolute !important;
	width: 1px;
	height: 1px;
	padding: 0;
	margin: -1px;
	overflow: hidden;
	clip: rect(0, 0, 0, 0);
	white-space: nowrap;
	border: 0;
}

.skip-link:focus {
	position: fixed;
	top: 12px;
	left: 12px;
	z-index: 1000;
	border-radius: 8px;
	background: var(--white);
	color: var(--ink);
	padding: 10px 16px;
	font-weight: 800;
}

:focus-visible {
	outline: 3px solid var(--blue-bright);
	outline-offset: 4px;
}

.section {
	padding: clamp(76px, 9vw, 126px) 0;
}

.section--night {
	position: relative;
	background: var(--night);
	color: var(--white);
}

.section--paper {
	background: var(--paper);
}

.section--mist {
	background: var(--mist);
}

.section--blueprint {
	position: relative;
	overflow: hidden;
	background:
		radial-gradient(circle at 84% 12%, rgba(53, 173, 244, 0.22), transparent 29%),
		linear-gradient(145deg, #071323 0%, #0b2440 55%, #071526 100%);
	color: var(--white);
}

.section--blueprint::before,
.hero::before {
	position: absolute;
	inset: 0;
	background-image:
		linear-gradient(rgba(71, 171, 237, 0.08) 1px, transparent 1px),
		linear-gradient(90deg, rgba(71, 171, 237, 0.08) 1px, transparent 1px);
	background-size: 54px 54px;
	-webkit-mask-image: linear-gradient(to bottom, black, transparent 88%);
	mask-image: linear-gradient(to bottom, black, transparent 88%);
	pointer-events: none;
	content: "";
}

.eyebrow {
	display: flex;
	align-items: center;
	gap: 11px;
	margin-bottom: 17px;
	color: #7d5d0d;
	font-size: 0.77rem;
	font-weight: 900;
	letter-spacing: 0.15em;
	line-height: 1.3;
	text-transform: uppercase;
}

.eyebrow::before {
	width: 30px;
	height: 3px;
	border-radius: 99px;
	background: currentColor;
	content: "";
}

.eyebrow--gold {
	color: var(--gold-soft);
}

.eyebrow--gold span {
	border: 1px solid rgba(255, 207, 88, 0.42);
	border-radius: 999px;
	padding: 7px 10px;
}

.section-heading {
	max-width: 820px;
	margin-bottom: 52px;
}

.section-heading--wide {
	max-width: 970px;
}

.section-heading h2,
.split h2,
.author-feature h2,
.footer-cta h2,
.page-hero h1,
.content-title {
	margin-bottom: 20px;
	font-size: clamp(2.2rem, 5.2vw, 4.65rem);
	font-weight: 860;
	letter-spacing: -0.055em;
	line-height: 0.99;
}

.section-heading p:last-child,
.split > div > p,
.large-copy {
	color: var(--slate);
	font-size: clamp(1.05rem, 1.7vw, 1.25rem);
	line-height: 1.65;
}

.button-row {
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	gap: 12px;
}

.button {
	display: inline-flex;
	min-height: 54px;
	align-items: center;
	justify-content: center;
	gap: 10px;
	border: 1px solid transparent;
	border-radius: 10px;
	padding: 14px 20px;
	font-size: 0.94rem;
	font-weight: 850;
	line-height: 1.2;
	text-align: center;
	text-decoration: none;
	transition: transform 180ms ease, background-color 180ms ease, border-color 180ms ease, color 180ms ease;
}

.button:hover {
	transform: translateY(-2px);
}

.button--gold {
	background: var(--gold);
	color: var(--night);
	box-shadow: 0 12px 30px rgba(240, 186, 54, 0.2);
}

.button--gold:hover {
	background: var(--gold-soft);
}

.button--ghost {
	border-color: rgba(255, 255, 255, 0.26);
	background: rgba(255, 255, 255, 0.04);
	color: var(--white);
}

.button--ghost:hover {
	border-color: rgba(255, 255, 255, 0.7);
	background: rgba(255, 255, 255, 0.1);
}

.button--ink {
	background: var(--ink);
	color: var(--white);
}

.button--ink:hover {
	background: var(--navy-2);
}

.text-link {
	display: inline-flex;
	align-items: center;
	gap: 9px;
	color: var(--ink);
	font-weight: 850;
	text-decoration: underline;
	text-decoration-color: var(--gold);
	text-decoration-thickness: 3px;
	text-underline-offset: 6px;
}

.text-link--light {
	color: var(--white);
}

.site-header {
	position: sticky;
	top: 0;
	z-index: 100;
	height: var(--header-height);
	border-bottom: 1px solid rgba(255, 255, 255, 0.11);
	background: rgba(4, 10, 20, 0.88);
	color: var(--white);
	-webkit-backdrop-filter: blur(18px);
	backdrop-filter: blur(18px);
	transition: height 180ms ease, box-shadow 180ms ease;
}

.site-header.is-scrolled {
	height: 74px;
	box-shadow: 0 16px 40px rgba(0, 0, 0, 0.22);
}

.site-header__inner {
	display: flex;
	height: 100%;
	align-items: center;
	justify-content: space-between;
	gap: 28px;
}

.brand {
	display: inline-flex;
	min-width: max-content;
	align-items: center;
	gap: 11px;
	color: var(--white);
	text-decoration: none;
}

.brand__mark {
	display: grid;
	width: 42px;
	height: 42px;
	place-items: center;
	border: 1px solid rgba(81, 196, 255, 0.54);
	border-radius: 9px;
	background: linear-gradient(145deg, rgba(81, 196, 255, 0.18), rgba(240, 186, 54, 0.12));
	color: var(--blue-bright);
	font-size: 0.74rem;
	font-weight: 950;
	letter-spacing: -0.04em;
}

.brand__name {
	display: grid;
	line-height: 1;
	text-transform: uppercase;
}

.brand__name strong {
	font-size: 0.9rem;
	letter-spacing: 0.11em;
}

.brand__name small {
	margin-top: 6px;
	color: var(--gold-soft);
	font-size: 0.62rem;
	font-weight: 750;
	letter-spacing: 0.23em;
}

.custom-logo-link,
.custom-logo {
	display: block;
	width: auto;
	max-height: 52px;
}

.site-nav {
	display: flex;
	align-items: center;
	gap: 26px;
}

.site-nav__list {
	display: flex;
	align-items: center;
	gap: 26px;
	margin: 0;
	padding: 0;
	list-style: none;
}

.site-nav__list a {
	position: relative;
	color: #dbe8f4;
	font-size: 0.86rem;
	font-weight: 740;
	text-decoration: none;
}

.site-nav__list a::after {
	position: absolute;
	right: 0;
	bottom: -8px;
	left: 0;
	height: 2px;
	border-radius: 99px;
	background: var(--gold);
	transform: scaleX(0);
	transform-origin: right;
	transition: transform 180ms ease;
	content: "";
}

.site-nav__list a:hover::after,
.site-nav__list .current-menu-item a::after {
	transform: scaleX(1);
	transform-origin: left;
}

.site-nav__button {
	display: inline-flex;
	min-height: 42px;
	align-items: center;
	gap: 8px;
	border-radius: 8px;
	background: var(--gold);
	color: var(--night);
	padding: 9px 14px;
	font-size: 0.78rem;
	font-weight: 900;
	line-height: 1;
	text-decoration: none;
}

.menu-toggle {
	display: none;
	width: 46px;
	height: 46px;
	place-items: center;
	border: 1px solid rgba(255, 255, 255, 0.2);
	border-radius: 9px;
	background: transparent;
	color: var(--white);
}

.menu-toggle__bars {
	display: grid;
	gap: 6px;
}

.menu-toggle__bars i {
	display: block;
	width: 20px;
	height: 2px;
	background: currentColor;
	transition: transform 180ms ease;
}

.hero {
	min-height: calc(100svh - var(--header-height));
	overflow: hidden;
	background:
		radial-gradient(circle at 82% 38%, rgba(38, 150, 245, 0.21), transparent 28%),
		radial-gradient(circle at 64% 72%, rgba(240, 186, 54, 0.1), transparent 26%),
		linear-gradient(135deg, #030812 0%, #071426 58%, #050d1a 100%);
}

.hero__glow {
	position: absolute;
	top: 8%;
	right: 4%;
	width: 12px;
	height: 12px;
	border-radius: 50%;
	background: var(--gold-soft);
	box-shadow: 0 0 18px 7px rgba(255, 207, 88, 0.65), 0 0 90px 36px rgba(255, 207, 88, 0.18);
}

.hero__grid {
	position: relative;
	z-index: 1;
	display: grid;
	min-height: calc(100svh - var(--header-height));
	grid-template-columns: minmax(0, 0.9fr) minmax(490px, 1.1fr);
	align-items: center;
	gap: clamp(30px, 4vw, 72px);
	padding-top: 56px;
	padding-bottom: 64px;
}

.hero__copy {
	position: relative;
	z-index: 2;
}

.hero h1 {
	max-width: 690px;
	margin-bottom: 27px;
	font-size: clamp(3.75rem, 7.8vw, 7.5rem);
	font-weight: 900;
	letter-spacing: -0.07em;
	line-height: 0.81;
	text-transform: uppercase;
}

.hero h1 span {
	display: block;
	margin-bottom: 19px;
	font-size: 0.36em;
	letter-spacing: -0.045em;
	line-height: 1;
}

.hero h1 em {
	color: var(--blue-bright);
	font-style: normal;
}

.hero__lede {
	max-width: 670px;
	margin-bottom: 17px;
	color: #dfeaf5;
	font-size: clamp(1.08rem, 1.65vw, 1.3rem);
	line-height: 1.55;
}

.hero__byline {
	margin-bottom: 29px;
	color: #9eb5c9;
	font-size: 0.95rem;
}

.hero__byline strong {
	color: var(--white);
}

.retail-note {
	margin: 16px 0 0;
	color: #88a0b7;
	font-size: 0.76rem;
}

.hero__media {
	position: relative;
	margin: 0 -90px 0 -30px;
	filter: drop-shadow(0 42px 70px rgba(0, 0, 0, 0.5));
}

.hero__media img {
	position: relative;
	z-index: 1;
	width: 100%;
}

.hero__orbit {
	position: absolute;
	top: 6%;
	right: 6%;
	bottom: 4%;
	left: 8%;
	border: 1px solid rgba(81, 196, 255, 0.3);
	border-radius: 50%;
	box-shadow: 0 0 80px rgba(53, 173, 244, 0.14) inset;
	transform: rotate(-12deg);
}

.fact-strip {
	position: relative;
	z-index: 2;
	border-top: 1px solid rgba(255, 255, 255, 0.1);
	border-bottom: 1px solid #dce3e9;
	background: var(--white);
}

.fact-strip__grid {
	display: grid;
	grid-template-columns: repeat(4, 1fr);
}

.fact-strip__grid div {
	display: flex;
	min-height: 116px;
	align-items: center;
	gap: 13px;
	border-right: 1px solid var(--line);
	padding: 20px 30px;
}

.fact-strip__grid div:last-child {
	border-right: 0;
}

.fact-strip strong {
	color: var(--navy-2);
	font-size: 2.35rem;
	letter-spacing: -0.06em;
	line-height: 1;
}

.fact-strip span {
	color: var(--muted);
	font-size: 0.77rem;
	font-weight: 780;
	letter-spacing: 0.03em;
	line-height: 1.35;
	text-transform: uppercase;
}

.principle-grid {
	display: grid;
	grid-template-columns: repeat(3, 1fr);
	gap: 18px;
}

.number-card {
	position: relative;
	min-height: 330px;
	overflow: hidden;
	border: 1px solid var(--line);
	border-radius: var(--radius);
	background: var(--white);
	padding: 30px;
	box-shadow: 0 12px 36px rgba(9, 30, 51, 0.06);
}

.number-card::after {
	position: absolute;
	right: -42px;
	bottom: -56px;
	width: 160px;
	height: 160px;
	border: 1px solid rgba(53, 173, 244, 0.2);
	border-radius: 50%;
	content: "";
}

.number-card > span {
	display: inline-grid;
	width: 47px;
	height: 47px;
	margin-bottom: 76px;
	place-items: center;
	border-radius: 10px;
	background: var(--mist);
	color: #2878aa;
	font-size: 0.78rem;
	font-weight: 900;
}

.number-card h3 {
	margin-bottom: 11px;
	font-size: 1.45rem;
	letter-spacing: -0.03em;
	line-height: 1.15;
}

.number-card p {
	margin-bottom: 0;
	color: var(--slate);
}

.split {
	position: relative;
	display: grid;
	grid-template-columns: minmax(0, 0.8fr) minmax(520px, 1.2fr);
	align-items: center;
	gap: clamp(50px, 8vw, 110px);
}

.split--visual > div > p {
	color: #c3d1dd;
}

.diagram-card {
	margin: 0;
	border: 1px solid rgba(255, 255, 255, 0.14);
	border-radius: var(--radius);
	padding: 12px;
	box-shadow: 0 30px 90px rgba(0, 0, 0, 0.28);
}

.diagram-card img {
	width: 100%;
	border-radius: 10px;
}

.diagram-card figcaption {
	padding: 12px 7px 3px;
	color: #9db0c1;
	font-size: 0.78rem;
}

.split--intro {
	grid-template-columns: minmax(290px, 0.68fr) minmax(0, 1.32fr);
	align-items: start;
}

.section-heading--sticky {
	position: sticky;
	top: 125px;
	margin: 0;
}

.topic-list {
	border-top: 1px solid var(--line);
}

.topic-list article {
	display: grid;
	grid-template-columns: 70px 1fr;
	gap: 18px;
	border-bottom: 1px solid var(--line);
	padding: 29px 0;
}

.topic-list article > span {
	color: #2a83b9;
	font-size: 0.76rem;
	font-weight: 900;
	letter-spacing: 0.12em;
}

.topic-list h3 {
	margin-bottom: 7px;
	font-size: 1.35rem;
	letter-spacing: -0.025em;
	line-height: 1.2;
}

.topic-list p {
	margin: 0;
	color: var(--slate);
}

.roadmap-card {
	overflow: hidden;
	margin: 0 0 28px;
	border: 1px solid #cbd6df;
	border-radius: var(--radius);
	background: var(--white);
	box-shadow: var(--shadow);
}

.roadmap-card img {
	width: 100%;
}

.phase-grid {
	display: grid;
	grid-template-columns: repeat(3, 1fr);
	gap: 16px;
}

.phase-grid article {
	border-top: 4px solid var(--gold);
	border-radius: 0 0 var(--radius-sm) var(--radius-sm);
	background: var(--white);
	padding: 26px;
}

.phase-grid span {
	color: #8a650d;
	font-size: 0.72rem;
	font-weight: 900;
	letter-spacing: 0.11em;
	text-transform: uppercase;
}

.phase-grid h3 {
	margin: 11px 0 8px;
	font-size: 1.28rem;
	line-height: 1.2;
}

.phase-grid p {
	margin: 0;
	color: var(--slate);
	font-size: 0.94rem;
}

.excerpt-feature {
	overflow: hidden;
	background:
		radial-gradient(circle at 76% 40%, rgba(45, 160, 235, 0.24), transparent 30%),
		linear-gradient(145deg, #030811, #07182c 65%, #061120);
}

.excerpt-feature__grid {
	display: grid;
	grid-template-columns: minmax(0, 1.15fr) minmax(280px, 0.55fr);
	align-items: center;
	gap: clamp(60px, 10vw, 140px);
}

.excerpt-feature blockquote {
	max-width: 780px;
	margin-bottom: 24px;
	color: var(--white);
	font-size: clamp(2.3rem, 5vw, 4.8rem);
	font-weight: 830;
	letter-spacing: -0.055em;
	line-height: 1.04;
}

.excerpt-feature blockquote + p {
	max-width: 680px;
	margin-bottom: 31px;
	color: #aec1d2;
	font-size: 1.1rem;
}

.cover-card {
	position: relative;
	margin: 0;
	transform: rotate(2.5deg);
	filter: drop-shadow(0 28px 48px rgba(0, 0, 0, 0.54));
}

.cover-card::before {
	position: absolute;
	top: 1.5%;
	right: -4%;
	bottom: 1.5%;
	left: 3%;
	z-index: -1;
	border-radius: 4px;
	background: #e0ddcf;
	box-shadow: 6px 0 0 #b9b6a9, 12px 0 0 #6e6e6b;
	content: "";
}

.cover-card img {
	width: 100%;
	border-radius: 3px;
}

.author-feature__grid {
	display: grid;
	grid-template-columns: minmax(260px, 0.52fr) minmax(0, 1fr);
	align-items: center;
	gap: clamp(54px, 9vw, 130px);
}

.author-monogram {
	position: relative;
	display: grid;
	max-width: 420px;
	aspect-ratio: 1;
	place-items: center;
	overflow: hidden;
	border-radius: 50%;
	background:
		radial-gradient(circle at 70% 26%, rgba(240, 186, 54, 0.54), transparent 7%),
		linear-gradient(145deg, var(--navy-2), var(--night));
	color: var(--white);
	box-shadow: var(--shadow);
}

.author-monogram::before,
.author-monogram::after {
	position: absolute;
	border: 1px solid rgba(81, 196, 255, 0.3);
	border-radius: 50%;
	content: "";
}

.author-monogram::before {
	width: 77%;
	height: 77%;
}

.author-monogram::after {
	width: 51%;
	height: 51%;
}

.author-monogram span {
	position: relative;
	z-index: 1;
	font-size: clamp(4rem, 10vw, 8rem);
	font-weight: 900;
	letter-spacing: -0.08em;
}

.author-monogram i {
	position: absolute;
	right: 10%;
	bottom: 22%;
	left: 10%;
	height: 3px;
	background: linear-gradient(90deg, transparent, var(--gold), transparent);
	transform: rotate(-22deg);
}

.author-feature h2 {
	margin-bottom: 25px;
}

.author-feature .large-copy {
	color: var(--ink);
	font-weight: 690;
}

.author-feature .button-row {
	margin-top: 32px;
}

.faq-layout {
	display: grid;
	grid-template-columns: minmax(260px, 0.7fr) minmax(0, 1.3fr);
	align-items: start;
	gap: clamp(50px, 8vw, 100px);
}

.faq-list {
	border-top: 1px solid #bdcad5;
}

.faq-list details {
	border-bottom: 1px solid #bdcad5;
}

.faq-list summary {
	position: relative;
	cursor: pointer;
	list-style: none;
	padding: 25px 56px 25px 0;
	font-size: 1.1rem;
	font-weight: 820;
	line-height: 1.35;
}

.faq-list summary::-webkit-details-marker {
	display: none;
}

.faq-list summary::after {
	position: absolute;
	top: 23px;
	right: 0;
	display: grid;
	width: 31px;
	height: 31px;
	place-items: center;
	border: 1px solid #aebdca;
	border-radius: 50%;
	color: #2f709a;
	content: "+";
}

.faq-list details[open] summary::after {
	content: "−";
}

.faq-list details p {
	max-width: 720px;
	margin: -6px 0 25px;
	color: var(--slate);
}

.site-footer {
	border-top: 5px solid var(--gold);
	background: #030812;
	color: var(--white);
}

.footer-cta {
	display: grid;
	grid-template-columns: minmax(0, 1.3fr) minmax(300px, 0.7fr);
	align-items: center;
	gap: 60px;
	border-bottom: 1px solid rgba(255, 255, 255, 0.12);
	padding: 74px 0;
}

.footer-cta h2 {
	max-width: 720px;
	margin: 0;
	font-size: clamp(2.2rem, 4.8vw, 4rem);
}

.footer-cta__action {
	text-align: right;
}

.footer-cta__action p {
	margin: 12px 0 0;
	color: #8095aa;
	font-size: 0.72rem;
}

.footer-main {
	display: grid;
	grid-template-columns: auto minmax(220px, 1fr) auto;
	align-items: center;
	gap: 42px;
	padding: 49px 0;
}

.footer-main__note {
	max-width: 430px;
	margin: 0;
	color: #8fa2b5;
	font-size: 0.86rem;
}

.footer-nav {
	display: flex;
	flex-wrap: wrap;
	gap: 13px 22px;
	justify-content: flex-end;
	margin: 0;
	padding: 0;
	list-style: none;
}

.footer-nav a {
	color: #cad8e5;
	font-size: 0.8rem;
	font-weight: 720;
	text-decoration: none;
}

.footer-nav a:hover {
	color: var(--gold-soft);
}

.footer-bottom {
	display: flex;
	justify-content: space-between;
	gap: 30px;
	border-top: 1px solid rgba(255, 255, 255, 0.1);
	padding: 23px 0 29px;
}

.footer-bottom p {
	margin: 0;
	color: #6f8398;
	font-size: 0.72rem;
}

/* Internal pages */
.page-hero {
	position: relative;
	overflow: hidden;
	padding: clamp(74px, 10vw, 140px) 0 clamp(68px, 9vw, 116px);
	background:
		radial-gradient(circle at 80% 28%, rgba(53, 173, 244, 0.25), transparent 28%),
		linear-gradient(145deg, #030812, #0a203a);
	color: var(--white);
}

.page-hero::after {
	position: absolute;
	right: -90px;
	bottom: -160px;
	width: 540px;
	height: 540px;
	border: 1px solid rgba(81, 196, 255, 0.25);
	border-radius: 50%;
	box-shadow: 0 0 0 70px rgba(81, 196, 255, 0.04), 0 0 0 140px rgba(81, 196, 255, 0.025);
	content: "";
}

.page-hero .site-shell {
	position: relative;
	z-index: 1;
}

.page-hero h1 {
	max-width: 980px;
	margin-bottom: 24px;
}

.page-hero__lede {
	max-width: 790px;
	margin: 0;
	color: #bfd0df;
	font-size: clamp(1.08rem, 2vw, 1.35rem);
}

.page-hero .button-row {
	margin-top: 32px;
}

.book-overview {
	display: grid;
	grid-template-columns: minmax(260px, 0.52fr) minmax(0, 1fr);
	align-items: start;
	gap: clamp(55px, 9vw, 120px);
}

.book-overview__cover {
	position: sticky;
	top: 115px;
	margin: 0;
	filter: drop-shadow(0 30px 45px rgba(4, 16, 29, 0.22));
}

.book-overview__cover img {
	border-radius: 4px;
}

.book-overview__copy h2 {
	margin-bottom: 18px;
	font-size: clamp(2.1rem, 4.2vw, 3.9rem);
	letter-spacing: -0.05em;
	line-height: 1.05;
}

.book-overview__copy > p {
	color: var(--slate);
	font-size: 1.06rem;
}

.detail-list {
	display: grid;
	grid-template-columns: repeat(2, 1fr);
	margin: 33px 0 0;
	border-top: 1px solid var(--line);
}

.detail-list div {
	border-bottom: 1px solid var(--line);
	padding: 18px 0;
}

.detail-list div:nth-child(odd) {
	border-right: 1px solid var(--line);
	padding-right: 25px;
}

.detail-list div:nth-child(even) {
	padding-left: 25px;
}

.detail-list dt {
	color: var(--muted);
	font-size: 0.7rem;
	font-weight: 850;
	letter-spacing: 0.11em;
	text-transform: uppercase;
}

.detail-list dd {
	margin: 4px 0 0;
	font-weight: 780;
}

.contents-grid {
	display: grid;
	grid-template-columns: repeat(2, 1fr);
	gap: 0 42px;
	margin: 0;
	padding: 0;
	counter-reset: chapter;
	list-style: none;
}

.contents-grid li {
	display: grid;
	grid-template-columns: 44px 1fr;
	align-items: start;
	gap: 15px;
	border-bottom: 1px solid rgba(255, 255, 255, 0.14);
	padding: 20px 0;
	counter-increment: chapter;
}

.contents-grid li::before {
	color: var(--gold-soft);
	font-size: 0.75rem;
	font-weight: 900;
	letter-spacing: 0.1em;
	content: counter(chapter, decimal-leading-zero);
}

.contents-grid span {
	font-size: 1rem;
	font-weight: 720;
	line-height: 1.4;
}

.appendix-grid {
	display: grid;
	grid-template-columns: repeat(3, 1fr);
	gap: 15px;
}

.appendix-card {
	border: 1px solid var(--line);
	border-radius: var(--radius-sm);
	background: var(--white);
	padding: 24px;
}

.appendix-card span {
	color: #317da9;
	font-size: 0.73rem;
	font-weight: 900;
	letter-spacing: 0.1em;
	text-transform: uppercase;
}

.appendix-card h3 {
	margin: 10px 0 0;
	font-size: 1.1rem;
	line-height: 1.3;
}

.excerpt-index {
	display: flex;
	flex-wrap: wrap;
	gap: 9px;
	margin-top: 31px;
}

.excerpt-index a {
	border: 1px solid rgba(255, 255, 255, 0.25);
	border-radius: 999px;
	padding: 9px 13px;
	color: #d9e8f4;
	font-size: 0.78rem;
	font-weight: 800;
	text-decoration: none;
}

.excerpt-section {
	scroll-margin-top: 105px;
}

.excerpt-section:nth-child(even) {
	background: var(--mist);
}

.excerpt-grid {
	display: grid;
	grid-template-columns: minmax(0, 0.9fr) minmax(380px, 1.1fr);
	align-items: start;
	gap: clamp(55px, 8vw, 110px);
}

.excerpt-copy__number {
	display: inline-grid;
	width: 50px;
	height: 50px;
	margin-bottom: 24px;
	place-items: center;
	border-radius: 10px;
	background: var(--navy);
	color: var(--gold-soft);
	font-size: 0.8rem;
	font-weight: 900;
}

.excerpt-copy h2 {
	margin-bottom: 16px;
	font-size: clamp(2.1rem, 4vw, 3.7rem);
	letter-spacing: -0.05em;
	line-height: 1.05;
}

.excerpt-copy__lede {
	border-left: 4px solid var(--gold);
	padding-left: 18px;
	color: var(--slate);
	font-size: 1.1rem;
	font-weight: 690;
}

.excerpt-text p {
	color: #33495e;
}

.excerpt-text p:first-child {
	color: var(--ink);
	font-size: 1.22rem;
	font-weight: 730;
}

.excerpt-figure {
	margin: 29px 0 0;
	border: 1px solid var(--line);
	border-radius: var(--radius-sm);
	background: var(--white);
	padding: 10px;
	box-shadow: 0 18px 50px rgba(9, 28, 46, 0.08);
}

.excerpt-figure img {
	width: 100%;
	border-radius: 7px;
}

.excerpt-figure figcaption {
	padding: 11px 7px 3px;
	color: var(--muted);
	font-size: 0.75rem;
}

.sample-banner {
	display: grid;
	grid-template-columns: minmax(0, 1fr) auto;
	align-items: center;
	gap: 44px;
	border: 1px solid #c8d4de;
	border-radius: var(--radius);
	background: var(--white);
	padding: clamp(28px, 5vw, 50px);
	box-shadow: var(--shadow);
}

.sample-banner h2 {
	margin-bottom: 8px;
	font-size: clamp(1.8rem, 3.5vw, 3rem);
	letter-spacing: -0.045em;
	line-height: 1.08;
}

.sample-banner p {
	margin: 0;
	color: var(--slate);
}

.about-layout {
	display: grid;
	grid-template-columns: minmax(260px, 0.5fr) minmax(0, 1fr);
	align-items: start;
	gap: clamp(55px, 9vw, 120px);
}

.about-layout .author-monogram {
	position: sticky;
	top: 115px;
}

.prose {
	max-width: 780px;
}

.prose h2 {
	margin: 54px 0 16px;
	font-size: clamp(1.8rem, 3.3vw, 2.7rem);
	letter-spacing: -0.045em;
	line-height: 1.1;
}

.prose h2:first-child {
	margin-top: 0;
}

.prose p,
.prose li {
	color: #33495e;
}

.prose > p:first-of-type {
	color: var(--ink);
	font-size: 1.2rem;
	font-weight: 650;
}

.prose a {
	font-weight: 760;
	text-decoration-color: var(--gold);
	text-decoration-thickness: 2px;
	text-underline-offset: 3px;
}

.prose-callout {
	margin: 40px 0;
	border-left: 5px solid var(--gold);
	background: #fff6de;
	padding: 22px 26px;
}

.prose-callout p:last-child {
	margin-bottom: 0;
}

.generic-page {
	min-height: 55vh;
}

.generic-content {
	max-width: 800px;
}

.not-found {
	display: grid;
	min-height: calc(100svh - var(--header-height));
	place-items: center;
	padding: 80px 0;
	background: var(--night);
	color: var(--white);
	text-align: center;
}

.not-found strong {
	display: block;
	color: var(--gold-soft);
	font-size: clamp(5rem, 18vw, 12rem);
	line-height: 0.8;
}

.not-found h1 {
	margin: 30px 0 14px;
	font-size: clamp(2rem, 5vw, 4rem);
	letter-spacing: -0.05em;
}

.not-found p {
	margin-bottom: 28px;
	color: #9eb3c6;
}

@media (prefers-reduced-motion: no-preference) {
	.js-reveal [data-reveal] {
		opacity: 0;
		transform: translateY(20px);
		transition: opacity 650ms ease, transform 650ms ease;
	}

	.js-reveal [data-reveal].is-visible {
		opacity: 1;
		transform: none;
	}
}

@media (max-width: 1060px) {
	.site-nav__list {
		gap: 18px;
	}

	.site-nav__button {
		display: none;
	}

	.hero__grid {
		grid-template-columns: minmax(0, 0.9fr) minmax(400px, 1.1fr);
	}

	.hero__media {
		margin-right: -50px;
	}

	.fact-strip__grid div {
		padding-inline: 20px;
	}
}

@media (max-width: 880px) {
	:root {
		--header-height: 74px;
	}

	.site-shell {
		width: min(calc(100% - 36px), var(--shell));
	}

	.menu-toggle {
		display: grid;
	}

	.site-nav {
		position: fixed;
		top: var(--header-height);
		right: 0;
		bottom: 0;
		left: 0;
		display: block;
		visibility: hidden;
		background: rgba(3, 8, 18, 0.98);
		opacity: 0;
		padding: 32px 18px;
		transform: translateY(-10px);
		transition: opacity 180ms ease, transform 180ms ease, visibility 180ms ease;
	}

	.site-nav.is-open {
		visibility: visible;
		opacity: 1;
		transform: none;
	}

	.site-nav__list {
		display: grid;
		gap: 0;
	}

	.site-nav__list li {
		border-bottom: 1px solid rgba(255, 255, 255, 0.12);
	}

	.site-nav__list a {
		display: block;
		padding: 19px 5px;
		font-size: 1.05rem;
	}

	.site-nav__button {
		display: flex;
		min-height: 51px;
		justify-content: center;
		margin-top: 28px;
		font-size: 0.9rem;
	}

	.hero__grid {
		min-height: auto;
		grid-template-columns: 1fr;
		gap: 25px;
		padding-top: 70px;
		padding-bottom: 25px;
	}

	.hero h1 {
		max-width: 760px;
	}

	.hero__copy {
		max-width: 760px;
	}

	.hero__media {
		max-width: 760px;
		margin: 0 auto -20px;
	}

	.fact-strip__grid {
		grid-template-columns: repeat(2, 1fr);
	}

	.fact-strip__grid div:nth-child(2) {
		border-right: 0;
	}

	.fact-strip__grid div:nth-child(-n+2) {
		border-bottom: 1px solid var(--line);
	}

	.principle-grid,
	.phase-grid,
	.appendix-grid {
		grid-template-columns: 1fr;
	}

	.number-card {
		min-height: auto;
	}

	.number-card > span {
		margin-bottom: 50px;
	}

	.split,
	.split--intro,
	.excerpt-feature__grid,
	.author-feature__grid,
	.faq-layout,
	.book-overview,
	.excerpt-grid,
	.about-layout {
		grid-template-columns: 1fr;
	}

	.section-heading--sticky,
	.book-overview__cover,
	.about-layout .author-monogram {
		position: static;
	}

	.book-overview__cover,
	.about-layout .author-monogram {
		max-width: 440px;
		margin-inline: auto;
	}

	.excerpt-feature__grid {
		grid-template-columns: minmax(0, 1fr) 220px;
		gap: 40px;
	}

	.footer-cta {
		grid-template-columns: 1fr;
		gap: 30px;
	}

	.footer-cta__action {
		text-align: left;
	}

	.footer-main {
		grid-template-columns: 1fr;
		gap: 25px;
	}

	.footer-nav {
		justify-content: flex-start;
	}
}

@media (max-width: 640px) {
	body {
		font-size: 16px;
	}

	.site-shell {
		width: min(calc(100% - 28px), var(--shell));
	}

	.section {
		padding: 72px 0;
	}

	.section-heading {
		margin-bottom: 36px;
	}

	.brand__mark {
		width: 38px;
		height: 38px;
	}

	.hero__grid {
		padding-top: 48px;
	}

	.hero h1 {
		font-size: clamp(3.25rem, 18vw, 5rem);
		line-height: 0.84;
	}

	.hero h1 span {
		font-size: 0.32em;
	}

	.button-row {
		display: grid;
		width: 100%;
	}

	.button-row .button {
		width: 100%;
	}

	.hero__media {
		width: calc(100% + 28px);
		margin-left: -14px;
	}

	.fact-strip__grid div {
		min-height: 94px;
		gap: 9px;
		padding: 17px 14px;
	}

	.fact-strip strong {
		font-size: 1.85rem;
	}

	.fact-strip span {
		font-size: 0.65rem;
	}

	.number-card {
		padding: 25px;
	}

	.topic-list article {
		grid-template-columns: 45px 1fr;
		gap: 10px;
	}

	.roadmap-card {
		overflow-x: auto;
	}

	.roadmap-card img {
		width: 780px;
		max-width: none;
	}

	.excerpt-feature__grid {
		grid-template-columns: 1fr;
	}

	.cover-card {
		max-width: 270px;
		margin: 25px auto 0;
	}

	.author-monogram {
		max-width: 310px;
		margin-inline: auto;
	}

	.footer-cta {
		padding: 60px 0;
	}

	.footer-bottom {
		display: grid;
	}

	.contents-grid {
		grid-template-columns: 1fr;
	}

	.detail-list {
		grid-template-columns: 1fr;
	}

	.detail-list div:nth-child(odd) {
		border-right: 0;
		padding-right: 0;
	}

	.detail-list div:nth-child(even) {
		padding-left: 0;
	}

	.sample-banner {
		grid-template-columns: 1fr;
		gap: 24px;
	}
}

@media (prefers-reduced-motion: reduce) {
	html {
		scroll-behavior: auto;
	}

	*,
	*::before,
	*::after {
		scroll-behavior: auto !important;
		transition-duration: 0.01ms !important;
		animation-duration: 0.01ms !important;
		animation-iteration-count: 1 !important;
	}
}