/* =========================================================
   ChronoAge — Design Tokens ("Precision Instrument" system)
   ========================================================= */
:root {
	--ca-ink: #14213D;
	--ca-porcelain: #F5F6F3;
	--ca-surface: #FFFFFF;
	--ca-petrol: #1B6B69;
	--ca-petrol-dark: #14504E;
	--ca-amber: #D98E2B;
	--ca-hairline: #DADFDC;
	--ca-text-muted: #55606E;

	--ca-font-display: 'Fraunces', Georgia, serif;
	--ca-font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
	--ca-font-mono: 'IBM Plex Mono', ui-monospace, Menlo, monospace;

	--ca-radius: 14px;
	--ca-radius-sm: 8px;
	--ca-shadow: 0 1px 2px rgba(20,33,61,0.04), 0 8px 24px rgba(20,33,61,0.06);
	--ca-container: 1180px;
	--ca-container-narrow: 780px;
	--ca-header-h: 72px;
}

[data-theme="dark"] {
	--ca-ink: #F5F6F3;
	--ca-porcelain: #0F1B2E;
	--ca-surface: #16233C;
	--ca-hairline: #253248;
	--ca-text-muted: #9AA6B4;
	--ca-shadow: 0 1px 2px rgba(0,0,0,0.3), 0 8px 24px rgba(0,0,0,0.35);
}

/* =========================================================
   Reset & base
   ========================================================= */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
	html { scroll-behavior: auto; }
	*, *::before, *::after { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
}
body {
	margin: 0;
	background: var(--ca-porcelain);
	color: var(--ca-ink);
	font-family: var(--ca-font-body);
	font-size: 16px;
	line-height: 1.6;
	-webkit-font-smoothing: antialiased;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--ca-petrol); text-decoration: none; }
a:hover { text-decoration: underline; }
:focus-visible { outline: 2px solid var(--ca-amber); outline-offset: 2px; }

h1, h2, h3, h4 { font-family: var(--ca-font-display); font-weight: 600; line-height: 1.15; margin: 0 0 0.5em; color: var(--ca-ink); }
.ca-h1 { font-size: clamp(2rem, 4vw, 2.75rem); margin-top: 0.4em; }
h2 { font-size: clamp(1.5rem, 3vw, 2rem); }

.ca-skip-link {
	position: absolute; left: -9999px; top: 0; background: var(--ca-ink); color: #fff;
	padding: 12px 20px; z-index: 1000; border-radius: 0 0 8px 0;
}
.ca-skip-link:focus { left: 0; }

.ca-container { max-width: var(--ca-container); margin: 0 auto; padding: 0 24px; }
.ca-container--narrow { max-width: var(--ca-container-narrow); }
.ca-section { padding: 64px 0; }
.ca-section--muted { background: var(--ca-surface); }
.ca-eyebrow { display: inline-block; font-family: var(--ca-font-mono); font-size: 0.75rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--ca-petrol); margin-bottom: 8px; }

/* =========================================================
   Header
   ========================================================= */
.ca-header {
	position: sticky; top: 0; z-index: 100;
	background: color-mix(in srgb, var(--ca-porcelain) 88%, transparent);
	backdrop-filter: blur(8px);
	border-bottom: 1px solid var(--ca-hairline);
	height: var(--ca-header-h);
}
.ca-header__inner { display: flex; align-items: center; justify-content: space-between; height: 100%; gap: 24px; }
.ca-logo { display: flex; align-items: center; gap: 10px; color: var(--ca-ink); }
.ca-logo:hover { text-decoration: none; }
.ca-logo__mark { color: var(--ca-petrol); display: inline-flex; }
.ca-logo__text { font-family: var(--ca-font-display); font-weight: 600; font-size: 1.25rem; }

.ca-nav__list { list-style: none; display: flex; gap: 28px; margin: 0; padding: 0; }
.ca-nav__list a { color: var(--ca-ink); font-weight: 500; font-size: 0.95rem; }
.ca-nav__list a:hover { color: var(--ca-petrol); text-decoration: none; }

.ca-header__actions { display: flex; align-items: center; gap: 12px; }
.ca-theme-toggle, .ca-nav-toggle {
	background: transparent; border: 1px solid var(--ca-hairline); border-radius: 999px;
	width: 40px; height: 40px; display: inline-flex; align-items: center; justify-content: center;
	cursor: pointer; color: var(--ca-ink);
}
.ca-theme-toggle .ca-icon-moon { display: none; }
[data-theme="dark"] .ca-theme-toggle .ca-icon-sun { display: none; }
[data-theme="dark"] .ca-theme-toggle .ca-icon-moon { display: block; }
.ca-nav-toggle { display: none; flex-direction: column; gap: 4px; }
.ca-nav-toggle span { width: 18px; height: 2px; background: currentColor; }

@media (max-width: 900px) {
	.ca-nav { position: absolute; top: var(--ca-header-h); left: 0; right: 0; background: var(--ca-surface); border-bottom: 1px solid var(--ca-hairline); padding: 16px 24px; display: none; }
	.ca-nav.is-open { display: block; }
	.ca-nav__list { flex-direction: column; gap: 16px; }
	.ca-nav-toggle { display: inline-flex; }
}

/* =========================================================
   Buttons
   ========================================================= */
.ca-btn {
	display: inline-flex; align-items: center; gap: 6px;
	padding: 12px 22px; border-radius: 999px; font-weight: 600; font-size: 0.95rem;
	border: 1px solid transparent; cursor: pointer;
	transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.ca-btn:hover { text-decoration: none; transform: translateY(-1px); }
.ca-btn--primary { background: var(--ca-petrol); color: #fff; }
.ca-btn--primary:hover { background: var(--ca-petrol-dark); color: #fff; box-shadow: var(--ca-shadow); }
.ca-btn--secondary { background: transparent; border-color: var(--ca-ink); color: var(--ca-ink); }
.ca-btn--ghost { background: var(--ca-surface); border-color: var(--ca-hairline); color: var(--ca-ink); padding: 10px 16px; font-size: 0.875rem; border-radius: var(--ca-radius-sm); }
.ca-btn--ghost:hover { border-color: var(--ca-petrol); color: var(--ca-petrol); }
.ca-icon-btn { background: none; border: none; cursor: pointer; color: var(--ca-text-muted); font-size: 1.1rem; }

/* =========================================================
   Hero
   ========================================================= */
.ca-hero { padding: 56px 0 40px; }
.ca-hero__grid { display: grid; grid-template-columns: 1.1fr 0.9fr; gap: 48px; align-items: center; }
.ca-hero__sub { color: var(--ca-text-muted); font-size: 1.1rem; max-width: 46ch; }
.ca-trust-badges { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 20px; }
.ca-trust-badges span {
	font-family: var(--ca-font-mono); font-size: 0.75rem; color: var(--ca-petrol);
	border: 1px solid var(--ca-hairline); border-radius: 999px; padding: 6px 12px;
}
@media (max-width: 900px) { .ca-hero__grid { grid-template-columns: 1fr; } }

/* =========================================================
   Calculator component — the signature "ruler readout" card
   ========================================================= */
.ca-calc {
	background: var(--ca-surface); border: 1px solid var(--ca-hairline);
	border-radius: var(--ca-radius); box-shadow: var(--ca-shadow); overflow: hidden;
	padding: 0 24px 24px;
}
.ca-calc__ruler { display: flex; justify-content: space-between; padding: 10px 24px 8px; }
.ca-calc__ruler span { width: 1px; height: 10px; background: var(--ca-hairline); }
.ca-calc__ruler span:nth-child(4n+1) { height: 16px; background: var(--ca-petrol); }

.ca-calc__inputs { display: grid; gap: 16px; margin-bottom: 16px; }
.ca-calc--full .ca-calc__inputs { grid-template-columns: 1fr 1fr; }
.ca-calc__field { display: flex; flex-direction: column; gap: 6px; }
.ca-calc__field label { font-size: 0.85rem; font-weight: 600; }
.ca-calc__field input[type="date"] {
	font-family: var(--ca-font-mono); font-size: 1rem; padding: 12px 14px;
	border: 1px solid var(--ca-hairline); border-radius: var(--ca-radius-sm);
	background: var(--ca-porcelain); color: var(--ca-ink);
}
.ca-field-hint { font-size: 0.75rem; color: var(--ca-text-muted); }
.ca-switch { display: flex; align-items: center; gap: 8px; font-size: 0.875rem; cursor: pointer; }

.ca-readout {
	background: var(--ca-ink); color: #fff; border-radius: var(--ca-radius-sm);
	padding: 28px 24px; text-align: center; min-height: 96px;
	display: flex; align-items: center; justify-content: center; flex-direction: column; gap: 4px;
}
.ca-readout__placeholder { color: #9AA6B4; font-size: 0.95rem; }
.ca-readout__big { font-family: var(--ca-font-display); font-size: clamp(1.6rem, 4vw, 2.4rem); font-weight: 600; }
.ca-readout__clinical { font-family: var(--ca-font-mono); color: var(--ca-amber); font-size: 1.1rem; }
.ca-readout__sub { font-family: var(--ca-font-mono); font-size: 0.85rem; color: #9AA6B4; }

.ca-calc__actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }

.ca-calc__advanced, .ca-calc__batch { margin-top: 18px; border-top: 1px solid var(--ca-hairline); padding-top: 14px; }
.ca-calc__advanced summary, .ca-calc__batch summary { cursor: pointer; font-weight: 600; }
.ca-advanced-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 12px; margin-top: 14px; }
.ca-advanced-grid .stat { background: var(--ca-porcelain); border-radius: var(--ca-radius-sm); padding: 12px; }
.ca-advanced-grid .stat .label { font-size: 0.75rem; color: var(--ca-text-muted); display: block; }
.ca-advanced-grid .stat .value { font-family: var(--ca-font-mono); font-size: 1.1rem; font-weight: 600; }

.ca-batch__table { width: 100%; border-collapse: collapse; margin-top: 12px; }
.ca-batch__table th, .ca-batch__table td { text-align: left; padding: 8px; border-bottom: 1px solid var(--ca-hairline); font-size: 0.9rem; }
.ca-batch__table input[type="text"], .ca-batch__table input[type="date"] {
	width: 100%; padding: 8px; border: 1px solid var(--ca-hairline); border-radius: 6px; font-family: var(--ca-font-body);
}

.ca-calc--mini .ca-calc__link { display: inline-block; margin-top: 14px; font-weight: 600; }

/* =========================================================
   Cards & grids
   ========================================================= */
.ca-card-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; margin-top: 24px; }
.ca-card-grid--3 { grid-template-columns: repeat(3, 1fr); }
@media (max-width: 1000px) { .ca-card-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 620px) { .ca-card-grid, .ca-card-grid--3 { grid-template-columns: 1fr; } }

.ca-card {
	display: block; background: var(--ca-surface); border: 1px solid var(--ca-hairline);
	border-radius: var(--ca-radius); overflow: hidden; color: var(--ca-ink);
	transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.ca-card:hover { transform: translateY(-3px); box-shadow: var(--ca-shadow); text-decoration: none; }
.ca-card__media img { aspect-ratio: 16/10; object-fit: cover; }
.ca-card__body { padding: 18px; }
.ca-card__title { font-size: 1.05rem; margin-bottom: 6px; }
.ca-card__excerpt { color: var(--ca-text-muted); font-size: 0.9rem; margin: 0 0 10px; }
.ca-card__cta { font-family: var(--ca-font-mono); font-size: 0.8rem; color: var(--ca-petrol); font-weight: 600; }

.ca-mini-card { display: block; color: var(--ca-ink); }
.ca-mini-card:hover { text-decoration: none; }
.ca-mini-card h3 { font-size: 1rem; margin-top: 10px; }

/* =========================================================
   FAQ (native details/summary — zero JS)
   ========================================================= */
.ca-faq { border-top: 1px solid var(--ca-hairline); margin-top: 20px; }
.ca-faq__item { border-bottom: 1px solid var(--ca-hairline); padding: 16px 0; }
.ca-faq__question { cursor: pointer; font-weight: 600; list-style: none; display: flex; justify-content: space-between; }
.ca-faq__question::-webkit-details-marker { display: none; }
.ca-faq__question::after { content: '+'; font-family: var(--ca-font-mono); }
.ca-faq__item[open] .ca-faq__question::after { content: '−'; }
.ca-faq__answer { color: var(--ca-text-muted); padding-top: 10px; }

/* =========================================================
   Breadcrumbs
   ========================================================= */
.ca-breadcrumbs { margin: 16px 0 0; }
.ca-breadcrumbs ol { list-style: none; display: flex; flex-wrap: wrap; gap: 6px; padding: 0; margin: 0; font-size: 0.8rem; color: var(--ca-text-muted); }
.ca-breadcrumbs li:not(:last-child)::after { content: '/'; margin-left: 6px; color: var(--ca-hairline); }

/* =========================================================
   Trust block / disclaimer / professionals section
   ========================================================= */
.ca-trust-block { border-top: 1px solid var(--ca-hairline); margin-top: 40px; padding-top: 20px; color: var(--ca-text-muted); font-size: 0.85rem; }
.ca-disclaimer { font-style: italic; }
.ca-professionals { background: var(--ca-ink); color: #fff; }
.ca-professionals h2, .ca-professionals .ca-eyebrow { color: #fff; }
.ca-professionals p { color: #C7CEDA; max-width: 60ch; }

.ca-cta { background: var(--ca-petrol); color: #fff; text-align: center; padding: 56px 0; }
.ca-cta h2 { color: #fff; }
.ca-cta .ca-btn--primary { background: #fff; color: var(--ca-petrol); }
.ca-cta .ca-btn--primary:hover { background: var(--ca-porcelain); }

/* =========================================================
   Footer
   ========================================================= */
.ca-footer { background: var(--ca-ink); color: #C7CEDA; padding: 56px 0 24px; margin-top: 40px; }
.ca-footer__grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 32px; }
.ca-footer h4 { color: #fff; font-family: var(--ca-font-body); font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.06em; }
.ca-footer__list { list-style: none; padding: 0; margin: 0; display: grid; gap: 10px; }
.ca-footer__list a { color: #C7CEDA; font-size: 0.9rem; }
.ca-footer__list a:hover { color: #fff; }
.ca-footer__bottom { display: flex; justify-content: space-between; align-items: center; margin-top: 40px; padding-top: 20px; border-top: 1px solid rgba(255,255,255,0.1); font-size: 0.8rem; }
.ca-back-to-top { background: rgba(255,255,255,0.08); border: none; color: #fff; width: 36px; height: 36px; border-radius: 999px; cursor: pointer; }
@media (max-width: 900px) { .ca-footer__grid { grid-template-columns: 1fr 1fr; } }

/* =========================================================
   Blog / content typography
   ========================================================= */
.ca-content { max-width: 72ch; }
.ca-content h2 { margin-top: 1.6em; }
.ca-content p { color: var(--ca-ink); }
.ca-content table { width: 100%; border-collapse: collapse; margin: 1.5em 0; }
.ca-content th, .ca-content td { border: 1px solid var(--ca-hairline); padding: 10px; text-align: left; }
.ca-toc { background: var(--ca-surface); border: 1px solid var(--ca-hairline); border-radius: var(--ca-radius-sm); padding: 16px 20px; margin: 24px 0; max-width: 72ch; }
.ca-toc ol { margin: 8px 0 0; padding-left: 20px; }
.ca-share { display: flex; gap: 12px; align-items: center; margin: 32px 0; font-size: 0.9rem; }
.ca-related-posts { margin-top: 48px; border-top: 1px solid var(--ca-hairline); padding-top: 32px; }

/* Utility */
.screen-reader-text { position: absolute; left: -9999px; }

/* =========================================================
   Print (used by the "Print / Save PDF" calculator action)
   ========================================================= */
@media print {
	.ca-header, .ca-footer, .ca-calc__actions, .ca-nav-toggle,
	.ca-cta, .ca-professionals, .ca-share, .ca-toc, .ca-calc__batch { display: none !important; }
	body { background: #fff; }
	.ca-readout { background: #fff; color: #000; border: 1px solid #000; }
	.ca-readout__sub, .ca-readout__clinical { color: #333; }
	a { text-decoration: none; color: #000; }
}