:root {
  --paper-50: #fffdf7;
  --paper-100: #f8f4e8;
  --paper-200: #eee7d6;
  --graphite-950: #18221f;
  --graphite-800: #2c3935;
  --graphite-650: #4d5b56;
  --graphite-500: #68756f;
  --chalk-blue: #245d70;
  --chalk-blue-dark: #184554;
  --answer-green: #cde86b;
  --answer-green-dark: #274c2e;
  --eraser: #e86752;
  --line: rgba(36, 93, 112, 0.16);
  --line-strong: rgba(36, 93, 112, 0.3);
  --shadow-soft: 0 12px 34px rgba(44, 57, 53, 0.08);
  --shadow-lift: 0 18px 44px rgba(44, 57, 53, 0.12);
  --radius-sm: 10px;
  --radius-md: 18px;
  --radius-lg: 28px;
  --radius-pill: 999px;
  --page: min(1160px, calc(100vw - 40px));
  --display: Georgia, "Times New Roman", serif;
  --body: "Segoe UI", Arial, sans-serif;
  --mono: "Cascadia Code", "SFMono-Regular", Consolas, monospace;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--graphite-950);
  background:
    linear-gradient(rgba(36, 93, 112, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(36, 93, 112, 0.035) 1px, transparent 1px),
    var(--paper-50);
  background-size: 32px 32px;
  font-family: var(--body);
  font-size: 16px;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: -1;
  background: radial-gradient(circle at 82% 10%, rgba(205, 232, 107, 0.2), transparent 27rem);
}

img, svg { display: block; max-width: 100%; }

a { color: var(--chalk-blue-dark); text-underline-offset: 3px; }
a:hover { color: var(--chalk-blue); }

button, input, select { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }

:focus-visible {
  outline: 3px solid var(--eraser);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 1000;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  background: var(--graphite-950);
  color: white;
  transform: translateY(-140%);
}

.skip-link:focus { transform: translateY(0); }

.container { width: var(--page); margin-inline: auto; }
.section { padding: clamp(64px, 8vw, 108px) 0; }
.section-tight { padding: 52px 0; }
.section-tint { background: rgba(248, 244, 232, 0.74); border-block: 1px solid var(--line); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 18px;
  color: var(--chalk-blue-dark);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  line-height: 1.2;
  text-transform: uppercase;
}

.eyebrow::before {
  content: "";
  width: 28px;
  height: 2px;
  background: var(--eraser);
}

h1, h2, h3 { margin: 0; font-family: var(--display); line-height: 1.08; letter-spacing: -0.035em; }
h1 { max-width: 780px; font-size: clamp(3rem, 7vw, 6.6rem); }
h2 { font-size: clamp(2.2rem, 4.6vw, 4rem); }
h3 { font-size: clamp(1.35rem, 2.4vw, 1.85rem); }
p { margin: 0 0 1rem; }

.lede {
  max-width: 670px;
  margin-top: 24px;
  color: var(--graphite-650);
  font-size: clamp(1.08rem, 1.7vw, 1.3rem);
}

.section-heading { display: grid; gap: 16px; max-width: 780px; margin-bottom: 42px; }
.section-heading p { max-width: 650px; margin: 0; color: var(--graphite-650); font-size: 1.08rem; }
.section-heading.split { grid-template-columns: 1.3fr 0.7fr; max-width: none; align-items: end; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  border-bottom: 1px solid transparent;
  background: rgba(255, 253, 247, 0.9);
  backdrop-filter: blur(16px);
  transition: border-color 160ms ease, box-shadow 160ms ease;
}

.site-header.scrolled { border-color: var(--line); box-shadow: 0 8px 24px rgba(44, 57, 53, 0.05); }
.nav-shell { min-height: 76px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--graphite-950); font-weight: 850; text-decoration: none; letter-spacing: -0.02em; }
.brand-mark { width: 34px; height: 34px; }
.brand em { color: var(--chalk-blue); font-family: var(--display); font-style: normal; }

.nav-links { display: flex; align-items: center; gap: 6px; }
.nav-links a { min-height: 44px; display: inline-flex; align-items: center; padding: 0 13px; border-radius: var(--radius-pill); color: var(--graphite-650); font-size: 0.92rem; font-weight: 700; text-decoration: none; }
.nav-links a:hover, .nav-links a[aria-current="page"] { background: var(--paper-100); color: var(--graphite-950); }
.nav-links .nav-cta { margin-left: 8px; background: var(--graphite-950); color: white; }
.nav-links .nav-cta:hover { background: var(--chalk-blue-dark); color: white; }
.menu-toggle { display: none; width: 46px; height: 46px; border: 1px solid var(--line); border-radius: var(--radius-pill); background: var(--paper-50); color: var(--graphite-950); cursor: pointer; }

.hero { min-height: 710px; display: grid; align-items: center; padding: clamp(64px, 8vw, 112px) 0; overflow: hidden; }
.hero-grid { display: grid; grid-template-columns: 1.15fr 0.85fr; align-items: center; gap: clamp(40px, 7vw, 96px); }
.hero h1 span { position: relative; color: var(--chalk-blue); white-space: nowrap; }
.hero h1 span::after { content: ""; position: absolute; left: 0; right: 0; bottom: 0.02em; height: 0.14em; background: var(--answer-green); z-index: -1; transform: rotate(-1deg); }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }

.button {
  min-height: 50px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 0 20px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  background: var(--graphite-950);
  color: white;
  font-weight: 800;
  text-decoration: none;
  cursor: pointer;
  transition: transform 150ms ease, background 150ms ease, box-shadow 150ms ease;
}
.button:hover { background: var(--chalk-blue-dark); color: white; transform: translateY(-2px); box-shadow: var(--shadow-soft); }
.button.secondary { border-color: var(--line-strong); background: rgba(255,255,255,0.48); color: var(--graphite-950); }
.button.secondary:hover { background: var(--paper-100); }
.button.accent { background: var(--answer-green); color: var(--answer-green-dark); }
.button.accent:hover { background: #bdd95a; color: var(--answer-green-dark); }
.button.small { min-height: 44px; padding-inline: 16px; font-size: 0.9rem; }

.trust-line { display: flex; flex-wrap: wrap; gap: 20px; margin-top: 28px; color: var(--graphite-650); font-size: 0.88rem; font-weight: 700; }
.trust-line span { display: inline-flex; align-items: center; gap: 7px; }
.trust-line span::before { content: "✓"; color: var(--answer-green-dark); font-weight: 900; }

.coordinate-card {
  position: relative;
  min-height: 480px;
  padding: 34px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background:
    linear-gradient(rgba(36, 93, 112, 0.09) 1px, transparent 1px),
    linear-gradient(90deg, rgba(36, 93, 112, 0.09) 1px, transparent 1px),
    rgba(248, 244, 232, 0.9);
  background-size: 32px 32px;
  box-shadow: var(--shadow-lift);
}
.coordinate-card::before, .coordinate-card::after { content: ""; position: absolute; background: rgba(36, 93, 112, 0.25); }
.coordinate-card::before { width: 1px; top: 0; bottom: 0; left: 50%; }
.coordinate-card::after { height: 1px; left: 0; right: 0; top: 50%; }
.route-line { position: absolute; left: 17%; top: 68%; width: 70%; height: 4px; border-radius: var(--radius-pill); background: var(--chalk-blue); transform: rotate(-34deg); transform-origin: left center; }
.route-line::after { content: ""; position: absolute; right: -2px; top: -5px; width: 14px; height: 14px; border-radius: 50%; background: var(--answer-green); border: 3px solid var(--graphite-950); }
.route-note { position: absolute; z-index: 2; max-width: 180px; padding: 14px 16px; border-radius: var(--radius-sm); background: var(--paper-50); box-shadow: var(--shadow-soft); font-size: 0.9rem; font-weight: 750; }
.route-note small { display: block; color: var(--graphite-500); font-size: 0.7rem; font-weight: 800; letter-spacing: 0.08em; text-transform: uppercase; }
.route-note.start { left: 7%; bottom: 10%; transform: rotate(-2deg); }
.route-note.middle { right: 8%; top: 42%; transform: rotate(2deg); }
.route-note.finish { right: 5%; top: 7%; background: var(--answer-green); transform: rotate(-1deg); }
.formula-float { position: absolute; z-index: 1; color: rgba(24,34,31,0.22); font-family: var(--display); font-size: 2.1rem; font-style: italic; }
.formula-float.one { left: 8%; top: 14%; }
.formula-float.two { right: 10%; bottom: 14%; }

.proof-strip { border-block: 1px solid var(--line); background: rgba(255,255,255,0.56); }
.proof-grid { min-height: 90px; display: grid; grid-template-columns: repeat(4, 1fr); align-items: center; }
.proof-item { padding: 0 24px; border-right: 1px solid var(--line); }
.proof-item:first-child { padding-left: 0; }
.proof-item:last-child { border: 0; }
.proof-item strong { display: block; font-family: var(--display); font-size: 1.2rem; }
.proof-item span { color: var(--graphite-500); font-size: 0.82rem; }

.path-grid, .card-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.path-card, .content-card, .tool-card, .product-card {
  position: relative;
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(255, 253, 247, 0.88);
  box-shadow: var(--shadow-soft);
}
.path-card { padding-top: 74px; }
.path-number { position: absolute; top: 22px; left: 24px; color: var(--chalk-blue); font-family: var(--mono); font-size: 0.82rem; font-weight: 800; }
.path-card::before { content: ""; position: absolute; left: 25px; top: 51px; width: calc(100% - 50px); height: 1px; background: var(--line); }
.path-card p, .content-card p, .tool-card p, .product-card p { color: var(--graphite-650); }
.path-card a, .content-card > a { display: inline-flex; align-items: center; gap: 6px; margin-top: 12px; font-weight: 800; text-decoration: none; }

.diagnostic-shell { display: grid; grid-template-columns: 0.72fr 1.28fr; gap: clamp(28px, 5vw, 72px); align-items: start; }
.diagnostic-intro { position: sticky; top: 110px; }
.diagnostic-intro .math-note { margin-top: 28px; }
.quiz-card { padding: clamp(24px, 4vw, 44px); border: 1px solid var(--line); border-radius: var(--radius-lg); background: var(--paper-50); box-shadow: var(--shadow-lift); }
.quiz-progress { height: 6px; margin-bottom: 34px; overflow: hidden; border-radius: var(--radius-pill); background: var(--paper-200); }
.quiz-progress span { display: block; width: 33.333%; height: 100%; border-radius: inherit; background: var(--chalk-blue); transition: width 240ms ease; }
.quiz-step[hidden], .quiz-result[hidden] { display: none; }
.quiz-step h3 { margin-bottom: 20px; }
.choice-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }
.choice {
  min-height: 84px;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  background: white;
  color: var(--graphite-950);
  text-align: left;
  cursor: pointer;
  transition: border-color 150ms ease, transform 150ms ease, background 150ms ease;
}
.choice:hover { border-color: var(--chalk-blue); background: var(--paper-100); transform: translateY(-2px); }
.choice[aria-pressed="true"] { border-color: var(--chalk-blue); background: rgba(205, 232, 107, 0.24); box-shadow: inset 0 0 0 1px var(--chalk-blue); }
.choice-mark { width: 30px; height: 30px; display: grid; place-items: center; flex: 0 0 auto; border-radius: 50%; background: var(--paper-100); font-family: var(--display); font-weight: 900; }
.quiz-actions { display: flex; justify-content: space-between; gap: 12px; margin-top: 26px; }
.result-route { margin: 22px 0; padding: 20px; border-radius: var(--radius-md); background: var(--paper-100); border-left: 4px solid var(--answer-green-dark); }
.result-route strong { display: block; margin-bottom: 6px; }

.math-note { position: relative; padding: 24px 24px 24px 30px; border-radius: 2px 12px 12px 2px; background: #fff8b8; box-shadow: 4px 5px 0 rgba(44,57,53,0.08); transform: rotate(-1deg); }
.math-note::before { content: ""; position: absolute; top: 0; bottom: 0; left: 12px; border-left: 1px solid rgba(232,103,82,0.42); }
.math-note p:last-child { margin-bottom: 0; }

.article-grid { display: grid; grid-template-columns: 1.15fr 0.85fr; gap: 20px; }
.article-feature { min-height: 420px; display: flex; flex-direction: column; justify-content: flex-end; padding: clamp(28px,5vw,54px); border-radius: var(--radius-lg); background: var(--chalk-blue-dark); color: white; box-shadow: var(--shadow-lift); }
.article-feature p { max-width: 540px; color: rgba(255,255,255,0.76); }
.article-feature a { color: white; }
.article-stack { display: grid; gap: 20px; }
.content-card { display: flex; flex-direction: column; justify-content: space-between; min-height: 200px; }
.tag { display: inline-flex; width: max-content; margin-bottom: 18px; padding: 6px 10px; border-radius: var(--radius-pill); background: var(--paper-100); color: var(--chalk-blue-dark); font-size: 0.72rem; font-weight: 850; letter-spacing: 0.06em; text-transform: uppercase; }

.newsletter-panel { position: relative; padding: clamp(34px, 7vw, 78px); overflow: hidden; border-radius: var(--radius-lg); background: var(--graphite-950); color: white; box-shadow: var(--shadow-lift); }
.newsletter-panel::after { content: "y = mx + b"; position: absolute; right: -16px; bottom: -22px; color: rgba(205,232,107,0.12); font-family: var(--display); font-size: clamp(4rem, 10vw, 9rem); font-style: italic; }
.newsletter-panel > * { position: relative; z-index: 2; }
.newsletter-panel h2 { max-width: 660px; }
.newsletter-panel p { max-width: 620px; margin-top: 18px; color: rgba(255,255,255,0.7); }
.email-form { max-width: 620px; display: grid; grid-template-columns: 1fr auto; gap: 10px; margin-top: 26px; }
.email-form input { min-height: 54px; padding: 0 18px; border: 1px solid rgba(255,255,255,0.2); border-radius: var(--radius-pill); background: rgba(255,255,255,0.1); color: white; }
.email-form input::placeholder { color: rgba(255,255,255,0.58); }
.form-note { margin-top: 10px !important; color: rgba(255,255,255,0.55) !important; font-size: 0.78rem; }
.form-status { min-height: 24px; margin-top: 8px !important; color: var(--answer-green) !important; font-weight: 700; }

.page-hero { padding: clamp(68px, 10vw, 124px) 0 72px; }
.page-hero h1 { font-size: clamp(3rem, 6.5vw, 5.8rem); }
.breadcrumb { display: flex; flex-wrap: wrap; gap: 7px; margin-bottom: 28px; color: var(--graphite-500); font-size: 0.82rem; }
.breadcrumb a { color: inherit; }

.calculator-layout { display: grid; grid-template-columns: 0.9fr 1.1fr; gap: 24px; align-items: start; }
.calculator-card, .answer-card, .practice-card { padding: clamp(24px,4vw,40px); border: 1px solid var(--line); border-radius: var(--radius-lg); background: rgba(255,253,247,0.94); box-shadow: var(--shadow-soft); }
.equation-form { display: grid; gap: 20px; margin-top: 28px; }
.equation-row { display: grid; grid-template-columns: 1fr auto 1fr auto 1fr; align-items: center; gap: 10px; font-family: var(--display); font-size: 1.5rem; }
.equation-row input { width: 100%; min-height: 54px; padding: 0 12px; border: 1px solid var(--line-strong); border-radius: var(--radius-sm); background: white; text-align: center; }
.field-label { display: grid; gap: 8px; color: var(--graphite-650); font-size: 0.82rem; font-weight: 750; }
.answer-card { min-height: 430px; background: var(--graphite-950); color: white; }
.answer-empty { min-height: 330px; display: grid; place-items: center; color: rgba(255,255,255,0.5); text-align: center; }
.answer-value { display: inline-flex; margin: 18px 0 28px; padding: 10px 18px; border-radius: var(--radius-sm); background: var(--answer-green); color: var(--answer-green-dark); font-family: var(--mono); font-size: 1.4rem; font-weight: 900; }
.steps-list { display: grid; gap: 14px; margin: 0; padding: 0; list-style: none; }
.steps-list li { display: grid; grid-template-columns: 30px 1fr; gap: 12px; color: rgba(255,255,255,0.76); }
.steps-list span { width: 30px; height: 30px; display: grid; place-items: center; border: 1px solid rgba(255,255,255,0.18); border-radius: 50%; color: white; font-family: var(--mono); font-size: 0.8rem; }
.error-message { padding: 14px; border-radius: var(--radius-sm); background: rgba(232,103,82,0.18); color: #ffc6bb; }
.practice-card { margin-top: 24px; }
.practice-equation { margin: 24px 0; font-family: var(--display); font-size: clamp(2rem,4vw,3.4rem); text-align: center; }
.practice-controls { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; }
.practice-controls input { width: 150px; min-height: 48px; padding-inline: 12px; border: 1px solid var(--line-strong); border-radius: var(--radius-pill); text-align: center; }
.practice-feedback { min-height: 28px; margin-top: 16px; text-align: center; font-weight: 800; }

.filter-bar { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 28px; }
.filter-button { min-height: 44px; padding: 0 15px; border: 1px solid var(--line-strong); border-radius: var(--radius-pill); background: rgba(255,255,255,0.7); color: var(--graphite-650); font-weight: 800; cursor: pointer; }
.filter-button:hover, .filter-button[aria-pressed="true"] { background: var(--graphite-950); border-color: var(--graphite-950); color: white; }
.product-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.product-card { display: flex; flex-direction: column; min-height: 410px; }
.product-card[hidden] { display: none; }
.product-icon { width: 58px; height: 58px; display: grid; place-items: center; margin-bottom: 28px; border-radius: 50%; background: var(--paper-100); color: var(--chalk-blue); font-family: var(--display); font-size: 1.4rem; font-weight: 900; }
.product-card .fit { margin: 16px 0; padding: 13px 0; border-block: 1px solid var(--line); color: var(--graphite-800); font-size: 0.88rem; }
.product-card .button { margin-top: auto; }
.product-card .paid-label { margin-top: 10px; color: var(--graphite-500); font-size: 0.72rem; text-align: center; }
.disclosure-box { margin-bottom: 30px; padding: 18px 20px; border-radius: var(--radius-sm); background: rgba(205,232,107,0.22); border-left: 4px solid var(--answer-green-dark); color: var(--graphite-800); font-size: 0.9rem; }

.guide-layout { display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: clamp(36px, 7vw, 84px); align-items: start; }
.guide-content { max-width: 760px; }
.guide-content h2 { margin: 2.2em 0 0.5em; font-size: clamp(2rem,4vw,3rem); }
.guide-content h3 { margin: 1.8em 0 0.5em; }
.guide-content p, .guide-content li { color: var(--graphite-800); }
.guide-content li + li { margin-top: 8px; }
.guide-content .callout { margin: 30px 0; padding: 24px; border-radius: var(--radius-md); background: var(--paper-100); }
.guide-content .inline-product { margin: 26px 0; padding: 24px; border: 1px solid var(--line); border-radius: var(--radius-md); background: white; }
.guide-content .inline-product .button { margin-top: 10px; }
.guide-aside { position: sticky; top: 108px; display: grid; gap: 16px; }
.toc, .aside-card { padding: 22px; border: 1px solid var(--line); border-radius: var(--radius-md); background: rgba(255,253,247,0.94); }
.toc strong { display: block; margin-bottom: 12px; }
.toc a { display: block; padding: 5px 0; color: var(--graphite-650); font-size: 0.88rem; text-decoration: none; }
.toc a:hover { color: var(--chalk-blue); }
.meta-row { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 24px; color: var(--graphite-500); font-size: 0.85rem; }

.legal { max-width: 760px; }
.legal h2 { margin: 2.2em 0 0.5em; font-size: 2rem; }
.legal p, .legal li { color: var(--graphite-800); }

.site-footer { padding: 58px 0 28px; border-top: 1px solid var(--line); background: rgba(248,244,232,0.75); }
.footer-grid { display: grid; grid-template-columns: 1.2fr repeat(3, 0.6fr); gap: 36px; }
.footer-about { max-width: 340px; }
.footer-about p { margin-top: 16px; color: var(--graphite-650); font-size: 0.9rem; }
.footer-column strong { display: block; margin-bottom: 12px; font-size: 0.83rem; letter-spacing: 0.07em; text-transform: uppercase; }
.footer-column a { display: block; padding: 4px 0; color: var(--graphite-650); font-size: 0.9rem; text-decoration: none; }
.footer-bottom { display: flex; justify-content: space-between; gap: 24px; margin-top: 44px; padding-top: 20px; border-top: 1px solid var(--line); color: var(--graphite-500); font-size: 0.78rem; }
.affiliate-footer { max-width: 580px; }

.reveal { opacity: 0; transform: translateY(14px); transition: opacity 500ms ease, transform 500ms ease; }
.reveal.is-visible { opacity: 1; transform: none; }

@media (max-width: 900px) {
  .hero-grid, .diagnostic-shell, .calculator-layout, .article-grid, .guide-layout { grid-template-columns: 1fr; }
  .hero { min-height: auto; }
  .coordinate-card { min-height: 400px; }
  .proof-grid { grid-template-columns: repeat(2, 1fr); }
  .proof-item { min-height: 72px; display: grid; align-content: center; border-bottom: 1px solid var(--line); }
  .proof-item:nth-child(2) { border-right: 0; }
  .proof-item:nth-child(3), .proof-item:nth-child(4) { border-bottom: 0; }
  .path-grid, .card-grid, .product-grid { grid-template-columns: repeat(2, 1fr); }
  .diagnostic-intro, .guide-aside { position: static; }
  .section-heading.split { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1.2fr 1fr 1fr; }
  .footer-about { grid-column: 1 / -1; }
}

@media (max-width: 720px) {
  :root { --page: min(100% - 28px, 1160px); }
  h1 { font-size: clamp(2.75rem, 15vw, 4.3rem); }
  .nav-shell { min-height: 66px; }
  .menu-toggle { display: grid; place-items: center; }
  .nav-links { position: absolute; top: calc(100% + 1px); left: 14px; right: 14px; display: none; padding: 12px; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--paper-50); box-shadow: var(--shadow-lift); }
  .nav-links.open { display: grid; }
  .nav-links a { justify-content: center; }
  .nav-links .nav-cta { margin: 4px 0 0; }
  .hero { padding-top: 54px; }
  .hero-grid { gap: 44px; }
  .coordinate-card { min-height: 350px; padding: 20px; }
  .route-note { max-width: 140px; padding: 10px 12px; font-size: 0.77rem; }
  .proof-grid { grid-template-columns: 1fr 1fr; }
  .proof-item { padding: 12px 14px; }
  .path-grid, .card-grid, .product-grid, .choice-grid { grid-template-columns: 1fr; }
  .article-feature { min-height: 360px; }
  .email-form { grid-template-columns: 1fr; }
  .newsletter-panel .button { width: 100%; }
  .equation-row { grid-template-columns: 1fr auto 1fr; }
  .equation-row .equals { grid-column: 1 / -1; text-align: center; }
  .equation-row .field-label:last-child { grid-column: 2; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-about { grid-column: 1 / -1; }
  .footer-bottom { flex-direction: column; }
}

@media print {
  .site-header, .site-footer, .button, .newsletter-panel, .guide-aside { display: none !important; }
  body { background: white; color: black; }
  .section, .page-hero { padding: 24px 0; }
  a { color: black; text-decoration: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; }
  .reveal { opacity: 1; transform: none; }
}

/* ===================== Store page ===================== */
.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  margin: -1px; padding: 0; border: 0;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap;
}

.store-toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  margin-bottom: 18px;
}

.store-search { flex: 1 1 300px; display: block; }
.store-search input {
  width: 100%;
  min-height: 52px;
  padding: 0 20px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-pill);
  background: rgba(255,255,255,0.85);
  color: var(--graphite-950);
}
.store-search input:focus { outline: 3px solid var(--eraser); outline-offset: 2px; border-color: var(--chalk-blue); }
.store-search input::placeholder { color: var(--graphite-500); }

.store-count { color: var(--graphite-500); font-size: 0.9rem; font-weight: 700; }

.store-empty {
  padding: 44px 20px;
  border: 1px dashed var(--line-strong);
  border-radius: var(--radius-md);
  background: rgba(255,253,247,0.7);
  text-align: center;
  color: var(--graphite-650);
}
.store-empty p { margin-bottom: 18px; }

.store-loadmore { margin-top: 32px; text-align: center; }

.store-cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
  margin-top: 30px;
  padding: 30px 32px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: rgba(255, 253, 247, 0.85);
  box-shadow: var(--shadow-soft);
}
.store-cta h2 { font-size: clamp(1.7rem, 3vw, 2.5rem); }
.store-cta p { margin: 0; max-width: 660px; color: var(--graphite-650); font-size: 1.03rem; }
.store-cta p a { font-weight: 800; }
.store-cta h2 + p { margin-top: 10px; }
.store-cta .button { flex: 0 0 auto; }