/* ==========================================================================
   Applied AI School — main stylesheet
   ========================================================================== */

/* Fonts ------------------------------------------------------------------- *
 * Self-hosted variable fonts, latin subset. Anthropic's own faces (Anthropic
 * Serif / Anthropic Sans / Tiempos Text) are proprietary and cannot be used.
 * These reproduce the recipe: editorial serif display over a neutral sans.
 * -------------------------------------------------------------------------- */

@font-face {
	font-family: 'Newsreader';
	src: url('../fonts/newsreader-latin.woff2') format('woff2');
	font-weight: 300 700;
	font-style: normal;
	font-display: swap;
}

@font-face {
	font-family: 'Inter';
	src: url('../fonts/inter-latin.woff2') format('woff2');
	font-weight: 300 700;
	font-style: normal;
	font-display: swap;
}

:root {
	/*
	 * Role split copied from Anthropic's own tokens: the serif carries both
	 * display headings AND paragraph text, and the sans is reserved for
	 * "detail" — labels, navigation, buttons, prices, metadata. Setting body
	 * copy in the sans is what made the earlier pass feel generic.
	 */
	--aais-font-display: 'Newsreader', Georgia, 'Times New Roman', serif;
	--aais-font-body: 'Newsreader', Georgia, 'Times New Roman', serif;
	--aais-font-detail: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;

	/* Display is tightly tracked and tightly led; body is neither. */
	--aais-tracking-display: -0.02em;
	--aais-leading-display: 1.08;
	--aais-leading-body: 1.5;

	--aais-ink: #0d1117;
	--aais-muted: #5b6472;
	--aais-accent: #2f6df6;
	--aais-surface: #ffffff;
	--aais-surface-alt: #f5f7fa;
	--aais-accent-soft: #e8effe;
	--aais-line: #e4e8ee;
	--aais-radius: 12px;
	--aais-gutter: clamp(1.25rem, 4vw, 4rem);
}

/* Site header / footer ----------------------------------------------------- */

.skip-link {
	position: absolute;
	left: -9999px;
	z-index: 999;
	padding: 0.75rem 1rem;
	background: var(--aais-ink);
	color: #fff;
}

.skip-link:focus {
	left: 1rem;
	top: 1rem;
}

.site-header {
	position: sticky;
	top: 0;
	z-index: 100;
	border-bottom: 1px solid var(--aais-line);
	background: color-mix(in srgb, var(--aais-surface) 88%, transparent);
	backdrop-filter: saturate(180%) blur(12px);
	font-family: var(--aais-font-detail);
}

.site-header__inner {
	display: flex;
	align-items: center;
	gap: clamp(1rem, 3vw, 2.5rem);
	max-width: 1200px;
	margin: 0 auto;
	padding: 0.875rem var(--aais-gutter);
}

.site-header__wordmark {
	color: var(--aais-ink);
	font-family: var(--aais-font-display);
	font-size: 1.25rem;
	font-weight: 500;
	letter-spacing: -0.02em;
	text-decoration: none;
}

.site-header__brand img,
.custom-logo {
	display: block;
	width: auto;
	max-height: 36px;
}

.site-nav {
	flex: 1;
}

.site-nav__list {
	display: flex;
	flex-wrap: wrap;
	gap: 1.5rem;
	margin: 0;
	padding: 0;
	list-style: none;
}

.site-nav__list a {
	color: var(--aais-ink);
	font-size: 0.9375rem;
	font-weight: 500;
	text-decoration: none;
}

.site-nav__list a:hover {
	color: var(--aais-accent);
}

.site-header__actions {
	display: flex;
	align-items: center;
	gap: 1rem;
	margin-left: auto;
}

.site-header__link {
	color: var(--aais-ink);
	font-size: 0.9375rem;
	font-weight: 500;
	text-decoration: none;
	white-space: nowrap;
}

.btn--sm {
	padding: 0.5rem 1rem;
	font-size: 0.9375rem;
}

.site-footer {
	padding: clamp(2.5rem, 6vw, 4rem) var(--aais-gutter) 2rem;
	border-top: 1px solid var(--aais-line);
	background: var(--aais-surface);
	font-family: var(--aais-font-detail);
}

.site-footer__inner {
	display: flex;
	flex-wrap: wrap;
	justify-content: space-between;
	gap: 2rem;
	max-width: 1200px;
	margin: 0 auto;
}

.site-footer__wordmark {
	font-family: var(--aais-font-display);
	font-size: 1.125rem;
}

.site-footer__tagline {
	margin: 0.375rem 0 0;
	color: var(--aais-muted);
	font-size: 0.875rem;
}

.site-footer__list {
	display: flex;
	flex-wrap: wrap;
	gap: 1.25rem;
	margin: 0;
	padding: 0;
	list-style: none;
}

.site-footer__list a {
	color: var(--aais-muted);
	font-size: 0.875rem;
	text-decoration: none;
}

.site-footer__list a:hover {
	color: var(--aais-accent);
}

.site-footer__legal {
	max-width: 1200px;
	margin: 2.5rem auto 0;
	padding-top: 1.5rem;
	border-top: 1px solid var(--aais-line);
	color: var(--aais-muted);
	font-size: 0.8125rem;
}

@media (max-width: 720px) {
	.site-header__inner {
		flex-wrap: wrap;
	}

	.site-nav {
		order: 3;
		flex-basis: 100%;
	}
}

/* Base -------------------------------------------------------------------- *
 * Scoped to our own sections. Kirki injects global styles late in the document,
 * so we set type on our containers rather than relying on inheriting from body.
 * -------------------------------------------------------------------------- */

.aais-main {
	font-family: var(--aais-font-body);
	font-optical-sizing: auto;
	line-height: var(--aais-leading-body);
	-webkit-font-smoothing: antialiased;
}

/* Headings: serif at regular weight. Bold serif headlines read as newspaper;
   regular weight at large sizes is what makes it feel considered. */
.hero__title,
.why__title,
.courses__title,
.page-head__title,
.auth__title,
.course-card__title,
.principle__title {
	font-family: var(--aais-font-display);
	font-weight: 400;
	font-optical-sizing: auto;
	letter-spacing: var(--aais-tracking-display);
	line-height: var(--aais-leading-display);
}

/* Small headings need a touch more leading than a 4rem headline does. */
.course-card__title,
.principle__title {
	letter-spacing: -0.005em;
	line-height: 1.25;
}

/* "Detail" — anything the eye scans rather than reads. */
.section-eyebrow,
.hero__eyebrow,
.btn,
.site-nav__list a,
.site-header__link,
.site-footer__list a,
.site-footer__legal,
.course-card__meta,
.course-card__price,
.course-card__cta,
.pagination,
.aais-register__consent,
.auth__alt {
	font-family: var(--aais-font-detail);
}

/* Hero -------------------------------------------------------------------- */

.hero {
	display: grid;
	grid-template-columns: 1fr 1fr;
	align-items: center;
	gap: var(--aais-gutter);
	min-height: 700px;
	padding: var(--aais-gutter);
}

.hero__eyebrow {
	display: inline-block;
	margin-bottom: 1rem;
	color: var(--aais-accent);
	font-size: 0.875rem;
	font-weight: 600;
	letter-spacing: 0.08em;
	text-transform: uppercase;
}

.hero__title {
	margin: 0 0 1.25rem;
	color: var(--aais-ink);
	font-size: clamp(2.5rem, 5vw, 4.25rem);
	line-height: 1.05;
	letter-spacing: -0.02em;
}

.hero__lede {
	max-width: 46ch;
	margin: 0 0 2rem;
	color: var(--aais-muted);
	font-size: clamp(1rem, 1.4vw, 1.25rem);
	line-height: 1.6;
}

.hero__media {
	min-height: 400px;
	border-radius: var(--aais-radius);
	background: var(--aais-surface-alt);
}

/* Buttons ----------------------------------------------------------------- */

.btn {
	display: inline-block;
	padding: 0.875rem 1.75rem;
	border-radius: var(--aais-radius);
	font-weight: 600;
	text-decoration: none;
	transition: transform 0.15s ease, opacity 0.15s ease;
}

.btn--primary {
	background: var(--aais-accent);
	color: #fff;
}

.btn--primary:hover {
	transform: translateY(-1px);
	opacity: 0.92;
}

.btn--ghost {
	border: 1px solid var(--aais-line);
	background: transparent;
	color: var(--aais-ink);
}

.btn--ghost:hover {
	transform: translateY(-1px);
	border-color: var(--aais-muted);
}

/* Why Applied AI School --------------------------------------------------- */

.section-eyebrow {
	display: inline-block;
	margin-bottom: 1rem;
	color: var(--aais-accent);
	font-size: 0.875rem;
	font-weight: 600;
	letter-spacing: 0.08em;
	text-transform: uppercase;
}

.why {
	padding: clamp(3.5rem, 8vw, 7rem) var(--aais-gutter);
}

.why__inner {
	display: grid;
	grid-template-columns: 1fr 1fr;
	align-items: center;
	gap: clamp(2.5rem, 6vw, 5rem);
	max-width: 1200px;
	margin: 0 auto;
}

.why__title {
	margin: 0 0 1.25rem;
	color: var(--aais-ink);
	font-size: clamp(1.875rem, 3.4vw, 2.75rem);
	line-height: 1.15;
	letter-spacing: -0.02em;
}

.why__body {
	max-width: 52ch;
	margin: 0 0 2rem;
	color: var(--aais-muted);
	font-size: clamp(1rem, 1.2vw, 1.125rem);
	line-height: 1.65;
}

.why__actions {
	display: flex;
	flex-wrap: wrap;
	gap: 0.75rem;
}

/* The six principles: 2 columns x 3 rows. */
.why__principles {
	display: grid;
	grid-template-columns: repeat(2, 1fr);
	gap: 1rem;
	margin: 0;
	padding: 0;
	list-style: none;
}

.principle {
	padding: 1.5rem 1.25rem;
	border: 1px solid var(--aais-line);
	border-radius: var(--aais-radius);
	background: var(--aais-surface);
}

.principle__icon {
	display: flex;
	align-items: center;
	justify-content: center;
	width: 2.5rem;
	height: 2.5rem;
	margin-bottom: 0.875rem;
	border-radius: 9px;
	background: var(--aais-accent-soft);
	color: var(--aais-accent);
}

.principle__icon svg {
	width: 1.25rem;
	height: 1.25rem;
}

.principle__title {
	margin: 0 0 0.375rem;
	color: var(--aais-ink);
	font-size: 1rem;
	line-height: 1.3;
	letter-spacing: -0.01em;
}

.principle__line {
	margin: 0;
	color: var(--aais-muted);
	font-size: 0.875rem;
	line-height: 1.5;
}

/* Auth (signup / login) --------------------------------------------------- */

.auth {
	padding: clamp(3rem, 7vw, 5.5rem) var(--aais-gutter);
	background: var(--aais-surface-alt);
}

.auth__inner {
	max-width: 480px;
	margin: 0 auto;
	padding: clamp(1.75rem, 4vw, 2.75rem);
	border: 1px solid var(--aais-line);
	border-radius: var(--aais-radius);
	background: var(--aais-surface);
}

.auth__title {
	margin: 0 0 0.625rem;
	font-family: var(--aais-font-display);
	font-size: clamp(1.75rem, 3vw, 2.25rem);
	font-weight: 400;
	line-height: 1.15;
	letter-spacing: -0.02em;
}

.auth__lede {
	margin: 0 0 1.75rem;
	color: var(--aais-muted);
	font-size: 0.9375rem;
	line-height: 1.6;
}

/* Tutor renders its own form markup here; keep it full width and let its
   own styles do the work rather than fighting them. */
.auth__form > * {
	max-width: 100%;
}

.auth__alt {
	margin: 1.5rem 0 0;
	color: var(--aais-muted);
	font-size: 0.875rem;
	text-align: center;
}

.auth__alt a {
	color: var(--aais-accent);
	font-weight: 600;
}

/* Registration (social only) ---------------------------------------------- */

.aais-register__body {
	padding: 0 1.5rem;
}

.aais-register__note {
	margin: 0 0 1.5rem;
	color: var(--aais-muted);
	font-size: 0.9375rem;
	line-height: 1.6;
	text-align: center;
}

.aais-register__consent {
	display: flex;
	align-items: flex-start;
	gap: 0.625rem;
	margin-bottom: 1.25rem;
	font-size: 0.875rem;
	line-height: 1.5;
}

.aais-register__consent a {
	color: var(--aais-accent);
	font-weight: 600;
}

.aais-register__providers.is-locked {
	pointer-events: none;
	opacity: 0.45;
}

.aais-register__alt {
	margin: 1.5rem 0 0;
	color: var(--aais-muted);
	font-size: 0.875rem;
	text-align: center;
}

.aais-register__alt a {
	color: var(--aais-accent);
	font-weight: 600;
}

/* Staff sign-in (only rendered with ?staff=1) ----------------------------- */

.aais-staff {
	margin-top: 1.75rem;
	padding-top: 1.25rem;
	border-top: 1px solid var(--aais-line);
	font-family: var(--aais-font-detail);
}

.aais-staff summary {
	cursor: pointer;
	color: var(--aais-muted);
	font-size: 0.8125rem;
	letter-spacing: 0.04em;
	text-transform: uppercase;
}

.aais-staff label {
	display: block;
	margin-bottom: 0.75rem;
	color: var(--aais-muted);
	font-size: 0.875rem;
}

.aais-staff input[type="text"],
.aais-staff input[type="password"] {
	display: block;
	width: 100%;
	margin-top: 0.25rem;
	padding: 0.625rem 0.75rem;
	border: 1px solid var(--aais-line);
	border-radius: 8px;
	font: inherit;
}

.aais-staff input[type="submit"] {
	width: 100%;
	padding: 0.625rem 1rem;
	border: 0;
	border-radius: 8px;
	background: var(--aais-ink);
	color: #fff;
	font: inherit;
	font-weight: 600;
	cursor: pointer;
}

.aais-staff__note {
	margin: 0.875rem 0 0;
	font-size: 0.8125rem;
}

.aais-staff__note a {
	color: var(--aais-muted);
}

/* Courses ----------------------------------------------------------------- */

.courses {
	padding: var(--aais-gutter);
	background: var(--aais-surface-alt);
}

.courses__inner {
	max-width: 1200px;
	margin: 0 auto;
}

.courses__title {
	margin: 0 0 2rem;
	font-size: clamp(1.75rem, 3vw, 2.5rem);
	letter-spacing: -0.01em;
}

.courses__grid {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
	gap: 1.5rem;
}

.course-card {
	overflow: hidden;
	border-radius: var(--aais-radius);
	background: var(--aais-surface);
}

.course-card {
	display: flex;
	flex-direction: column;
	border: 1px solid var(--aais-line);
	transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.course-card:hover {
	transform: translateY(-2px);
	box-shadow: 0 12px 28px rgba(13, 17, 23, 0.08);
}

.course-card__media {
	display: block;
}

.course-card__media img {
	display: block;
	width: 100%;
	height: 200px;
	object-fit: cover;
}

.course-card__placeholder {
	display: block;
	height: 200px;
	background: linear-gradient(135deg, var(--aais-surface-alt), var(--aais-accent-soft));
}

.course-card__body {
	display: flex;
	flex: 1;
	flex-direction: column;
}

.course-card__meta {
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: 1rem;
	margin-top: auto;
	padding-top: 1rem;
}

.course-card__price {
	color: var(--aais-ink);
	font-size: 1rem;
	font-weight: 650;
}

.course-card__price--free {
	color: var(--aais-accent);
}

.course-card__cta {
	color: var(--aais-muted);
	font-size: 0.875rem;
	font-weight: 600;
}

.course-card:hover .course-card__cta {
	color: var(--aais-accent);
}

/* Archive page head ------------------------------------------------------- */

.page-head {
	padding: clamp(3rem, 7vw, 5rem) var(--aais-gutter) clamp(2rem, 4vw, 3rem);
}

.page-head__inner {
	max-width: 720px;
	margin: 0 auto;
	text-align: center;
}

.page-head__title {
	margin: 0 0 1rem;
	font-family: var(--aais-font-display);
	font-size: clamp(2rem, 4vw, 3.25rem);
	font-weight: 400;
	line-height: 1.1;
	letter-spacing: -0.02em;
}

.page-head__lede {
	margin: 0 auto;
	max-width: 56ch;
	color: var(--aais-muted);
	font-size: clamp(1rem, 1.3vw, 1.125rem);
	line-height: 1.65;
}

.courses--archive {
	background: transparent;
}

.courses__empty {
	color: var(--aais-muted);
	text-align: center;
}

.pagination {
	display: flex;
	justify-content: center;
	gap: 0.5rem;
	margin-top: 2.5rem;
}

.pagination .page-numbers {
	padding: 0.5rem 0.875rem;
	border: 1px solid var(--aais-line);
	border-radius: 8px;
	color: var(--aais-ink);
	font-size: 0.9375rem;
	text-decoration: none;
}

.pagination .page-numbers.current {
	border-color: var(--aais-accent);
	background: var(--aais-accent);
	color: #fff;
}

.course-card__body {
	padding: 1.25rem;
}

.course-card__title {
	margin: 0 0 0.5rem;
	font-size: 1.125rem;
	line-height: 1.3;
}

.course-card__title a {
	color: var(--aais-ink);
	text-decoration: none;
}

.course-card__excerpt {
	margin: 0;
	color: var(--aais-muted);
	font-size: 0.9375rem;
	line-height: 1.55;
}

/* Responsive -------------------------------------------------------------- */

@media (max-width: 860px) {
	.hero {
		grid-template-columns: 1fr;
		min-height: 0;
		padding-top: 3rem;
		padding-bottom: 3rem;
	}

	.hero__media {
		min-height: 240px;
	}

	/* Copy stacks above the principles; the 2 x 3 grid is kept. */
	.why__inner {
		grid-template-columns: 1fr;
	}
}

@media (max-width: 520px) {
	.why__principles {
		grid-template-columns: 1fr;
	}
}