:root {
  color-scheme: light dark;
  --bg: #f8faff;
  --surface: #ffffff;
  --ink: #161f35;
  --muted: #53617a;
  --line: #dce3ef;
  --accent: #285cdb;
  --glow: #e6eeff;
  --success: #1d7348; --success-bg: #e5f4eb;
  --danger: #b42318; --danger-bg: #fdeceb;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-synthesis: none;
  -webkit-font-smoothing: antialiased;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1423; --surface: #151f31; --ink: #f2f5ff; --muted: #a9b7d0;
    --line: #2b374d; --accent: #94b5ff; --glow: #14264b;
    --success: #7fd6a8; --success-bg: #153526; --danger: #ffa198; --danger-bg: #3d1d1f;
  }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--ink); font-size: 1rem; line-height: 1.6; }
a { color: var(--accent); text-underline-offset: .2em; }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 5px; }
.skip { position: fixed; top: .7rem; left: 1rem; padding: .7rem 1rem; background: var(--surface); z-index: 10; transform: translateY(-200%); }
.skip:focus { transform: none; }
.shell { max-width: 82rem; margin-inline: auto; padding-inline: clamp(1.25rem, 4vw, 3.5rem); }
.header { display: flex; align-items: center; justify-content: space-between; gap: 1rem; min-height: 6.5rem; }
.brand { color: var(--ink); font-size: 1.5rem; font-weight: 750; text-decoration: none; letter-spacing: -.06em; }
.navigation { display: flex; align-items: center; flex-wrap: wrap; gap: .5rem 1.4rem; }
.navigation > a { font-size: .9rem; color: var(--muted); text-decoration: none; padding-block: .65rem; }
.navigation > a:hover { color: var(--accent); }
.app-icon { display: block; width: 7.5rem; height: 7.5rem; border-radius: 27%; margin: 0 auto 1.8rem; box-shadow: 0 1rem 3.5rem -1.5rem var(--accent); }
.eyebrow { color: var(--muted); font-size: .9rem; font-weight: 550; margin: 0 0 1.2rem; }
h1 { font-size: clamp(2.6rem, 6vw, 4.5rem); letter-spacing: -.06em; line-height: 1.08; font-weight: 720; margin: 0 0 1.6rem; text-wrap: balance; overflow-wrap: break-word; hyphens: auto; }
h1 span { display: block; color: var(--accent); }
.intro { max-width: 39rem; margin: 0 auto; font-size: clamp(1.05rem, 2vw, 1.2rem); color: var(--muted); line-height: 1.75; text-wrap: pretty; }
.hero-note { font-size: .9rem; color: var(--muted); margin: 1.6rem 0 0; }
.app-store-badge { display: inline-flex; max-width: 100%; margin-top: 1.5rem; text-decoration: none; }
.app-store-badge img { display: block; width: min(180px, 100%); height: auto; }
.app-store-badge:focus-visible { outline: 3px solid var(--accent); outline-offset: 5px; }
.footer { border-top: 1px solid var(--line); margin-top: 2rem; padding-block: 3rem 2rem; color: var(--muted); font-size: .9rem; }
.footer p { margin: 0; }
.footer a { color: var(--muted); }
.footer a:hover, .footer a[aria-current="page"] { color: var(--accent); }
.footer-main { display: grid; grid-template-columns: 1.3fr 1fr 1fr; gap: 2.5rem; padding-bottom: 2.5rem; }
.footer-brand { display: grid; justify-items: start; align-content: start; gap: .6rem; }
.footer .brand { color: var(--ink); }
.footer-brand .app-store-badge { margin-top: .75rem; }
.footer-brand .app-store-badge img { width: auto; height: 40px; }
.footer .footer-heading { color: var(--ink); font-weight: 650; margin-bottom: .6rem; }
.footer-column ul { list-style: none; margin: 0; padding: 0; }
.footer-column a { display: inline-block; padding-block: .35rem; line-height: 1.45; text-decoration: none; }
.footer-column a:hover { text-decoration: underline; }
.footer-legal { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: .5rem 1.5rem; border-top: 1px solid var(--line); padding-top: 1.25rem; font-size: .85rem; }
.footer-links { display: flex; flex-wrap: wrap; gap: .5rem 1.5rem; }
.footer-links a { padding-block: .5rem; }
.legal { max-width: 47rem; margin-inline: auto; padding-block: 3.5rem; }
.legal h1 { font-size: clamp(2.6rem, 6vw, 3.8rem); }
.legal .intro { font-size: 1.15rem; max-width: none; }
.legal .updated { margin: 1.5rem 0 3rem; font-size: .875rem; color: var(--muted); }
.legal section { margin-block: 2rem; }
.legal h2 { font-size: 1.2rem; line-height: 1.4; letter-spacing: -.02em; margin: 0 0 .65rem; }
.legal section p { color: var(--muted); margin: 0; line-height: 1.8; overflow-wrap: anywhere; }
.legal .policy-links { display: flex; flex-wrap: wrap; gap: .6rem 1.4rem; font-size: .9rem; margin-block: 2rem; }
.error { min-height: 60vh; display: grid; align-content: center; padding-block: 4rem; }
.bookmark { max-width: 42rem; margin-inline: auto; padding-block: 2rem; }
.bookmark-heading { text-align: center; margin-bottom: 2.5rem; }
.bookmark-heading h1 { font-size: clamp(2.3rem, 6vw, 3.6rem); }
.bookmark-question { border: 1px solid var(--line); border-radius: 1.5rem; background: var(--surface); padding: clamp(1rem, 4vw, 2rem); }
.bookmark-question h2 { text-align: center; font-size: 1.3rem; line-height: 1.4; margin: 0; }
.domino-ring { display: block; width: min(100%, 24rem); margin: 1.5rem auto; }
.bookmark-choices { min-width: 0; margin: 0; padding: 0; border: 0; }
.bookmark-choices legend { width: 100%; padding: 0; margin-bottom: .75rem; text-align: center; color: var(--muted); font-size: .9rem; font-weight: 550; }
.bookmark-options { display: grid; grid-template-columns: 1fr 1fr; gap: .75rem; }
.bookmark-option { position: relative; display: flex; justify-content: center; align-items: center; min-height: 5rem; padding: .75rem; border: 1px solid var(--line); border-radius: 1rem; background: var(--surface); cursor: pointer; transition: border-color .15s, box-shadow .15s; }
.bookmark-option:hover { border-color: var(--accent); }
.bookmark-option input { position: absolute; width: 1px; height: 1px; margin: 0; opacity: 0; pointer-events: none; }
.bookmark-option input:focus-visible + .option-letter { outline: 3px solid var(--accent); outline-offset: 3px; border-radius: .2rem; }
.bookmark-option:has(input:focus-visible) { outline: 3px solid var(--accent); outline-offset: 3px; }
.bookmark-option:has(input:focus-visible) .option-letter { outline: none; }
.bookmark-option:has(input:checked) { border-color: var(--accent); background: var(--glow); box-shadow: inset 0 0 0 1px var(--accent); }
.bookmark-option:has(input:checked) .option-letter { color: var(--accent); font-weight: 700; }
.bookmark-options svg { display: block; width: 4rem; height: 7rem; }
.option-letter { position: absolute; top: .65rem; left: .85rem; color: var(--muted); }
/* After the reveal, confirm the correct option and flag a different choice. */
.bookmark-question:has(.bookmark-answer[open]) .is-correct { border-color: var(--success); background: var(--success-bg); box-shadow: inset 0 0 0 1px var(--success); }
.bookmark-question:has(.bookmark-answer[open]) .is-correct::after { content: "✓"; content: "✓" / ""; position: absolute; top: .55rem; right: .8rem; color: var(--success); font-weight: 750; }
.bookmark-question:has(.bookmark-answer[open]) .bookmark-option:not(.is-correct):has(input:checked) { border-color: var(--danger); background: var(--danger-bg); box-shadow: inset 0 0 0 1px var(--danger); }
.bookmark-question:has(.bookmark-answer[open]) .bookmark-option:not(.is-correct):has(input:checked) .option-letter { color: var(--danger); }
.more-puzzles { padding-top: 2.5rem; }
.more-puzzles h2 { font-size: 1.3rem; letter-spacing: -.03em; text-align: center; margin: 0 0 1rem; }
.puzzle-links { display: grid; gap: .75rem; list-style: none; margin: 0; padding: 0; }
.puzzle-links a { display: flex; align-items: center; gap: 1rem; padding: .85rem 1.1rem; border: 1px solid var(--line); border-radius: 1rem; background: var(--surface); color: var(--ink); font-weight: 600; line-height: 1.35; text-decoration: none; }
.puzzle-links a::after { content: "→"; content: "→" / ""; margin-left: auto; color: var(--accent); }
.puzzle-links a:hover { border-color: var(--accent); }
.puzzle-glyph { flex: none; display: grid; place-items: center; width: 2.5rem; height: 2.5rem; border-radius: .75rem; background: var(--glow); }
.puzzle-glyph-domino::before { content: ""; width: .8rem; height: 1.5rem; border: 2px solid var(--accent); border-radius: .3rem; background: linear-gradient(var(--accent), var(--accent)) center / 100% 2px no-repeat; }
.puzzle-glyph-code::before { content: "{ }"; color: var(--accent); font: 700 .8rem ui-monospace, monospace; }
@media (prefers-reduced-motion: reduce) { .bookmark-option { transition: none; } }
.bookmark code { font-family: ui-monospace, monospace; font-size: 1.6rem; }
.bookmark .reference { text-align: center; padding: 1.5rem; }
.bookmark-answer { margin-top: 1.5rem; border-top: 1px solid var(--line); }
.bookmark-answer summary { cursor: pointer; padding-block: 1.25rem; color: var(--accent); font-weight: 650; }
.bookmark-answer li { margin-block: 1rem; }
.bookmark-answer p { color: var(--muted); margin-top: .4rem; overflow-wrap: anywhere; }
.bookmark-install { text-align: center; padding-top: 2rem; }
.bookmark-install h2 { font-size: 1.5rem; letter-spacing: -.035em; }
.bookmark-install p { color: var(--muted); margin-bottom: 0; }
@media (max-width: 640px) {
  .header { min-height: 5.5rem; gap: .5rem; flex-wrap: wrap; padding-block: 1rem; }
  .navigation { gap: .75rem; }
  .app-icon { width: 6.5rem; height: 6.5rem; }
  h1 { letter-spacing: -.045em; }
  .footer-legal { align-items: flex-start; flex-direction: column; }
  .legal { padding-block: 2.5rem; }
}

/* Real app captures keep their full viewport and intrinsic proportions. */
.showcase { --lavender: #eae7fb; --mint: #e2f0e9; --blue: #e4ecfa; --lavender-ink: #5a46c8; --mint-ink: #1d7348; }
.showcase h2 { font-size: clamp(2rem, 3.7vw, 3.15rem); letter-spacing: -.05em; line-height: 1.12; margin: 0 0 1.25rem; text-wrap: balance; overflow-wrap: break-word; hyphens: auto; }
.showcase p { text-wrap: pretty; }
.showcase-hero { display: grid; grid-template-columns: 1.05fr 1fr; gap: clamp(2rem, 5vw, 5rem); align-items: center; padding-block: 3rem 5rem; }
.hero-copy .app-icon { width: 4.5rem; height: 4.5rem; margin: 0 0 2rem; }
.hero-copy h1 { font-size: clamp(2.8rem, 4.8vw, 4.1rem); }
.hero-copy .intro { margin: 0; max-width: 33rem; font-size: 1.1rem; }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 1rem 1.5rem; margin-top: 2rem; }
.hero-actions .app-store-badge { margin: 0; flex: 0 0 auto; }
.hero-actions .app-store-badge img { width: auto; height: 44px; }
.text-link { display: inline-flex; gap: .75rem; align-items: center; font-weight: 650; padding-block: .7rem; }
.hero-stage { display: grid; place-items: center; padding: 2.5rem 1.5rem; background: var(--lavender); border-radius: 3rem; }
.device-shell { position: relative; width: 100%; max-width: 300px; padding: 3px; border-radius: 2.65rem; background: linear-gradient(115deg, #8a909b, #d3d6db 18%, #666d78 42%, #b0b5bd 72%, #6e7580); box-shadow: 0 1.5rem 3rem -1.5rem #18223688; }
.device-shell::before, .device-shell::after { content: ""; position: absolute; width: 3px; background: #737b87; border-radius: 2px; }
.device-shell::before { left: -2px; top: 18%; height: 1.25rem; box-shadow: 0 2rem #737b87, 0 3.7rem #737b87; }
.device-shell::after { right: -2px; top: 28%; height: 3.1rem; }
.phone-frame { width: 100%; border: 6px solid #141820; border-radius: 2.45rem; overflow: hidden; background: #f2f2f7; }
.device-top { display: grid; place-items: center; height: 30px; background: #f2f2f7; }
.device-top span { display: block; width: 30%; height: 16px; border-radius: 20px; background: #101115; position: relative; }
.device-top span::after { content: ""; position: absolute; width: 6px; height: 6px; border-radius: 50%; background: #202a3f; right: 7px; top: 5px; }
.device-bottom { display: grid; place-items: center; height: 15px; }
.device-bottom span { width: 32%; height: 3px; border-radius: 4px; background: #22252b; }
.phone-frame img, .tablet-frame img { display: block; width: 100%; height: auto; }
.showcase-features { padding-block: 3rem 5rem; scroll-margin-top: 2rem; }
.section-heading { max-width: 43rem; margin-bottom: 2.5rem; }
.section-heading > p:last-child, .ipad-copy > p:last-child, .clip-copy > p { color: var(--muted); font-size: 1.1rem; }
.feature-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1.25rem; }
.feature-card { border: 1px solid var(--line); border-radius: 2rem; overflow: hidden; background: var(--surface); display: flex; flex-direction: column; }
.feature-copy { padding: 1.75rem 1.75rem 1rem; }
.feature-number { font-size: .8rem; font-weight: 650; color: var(--muted); }
.feature-copy h3 { font-size: 1.55rem; line-height: 1.2; letter-spacing: -.04em; margin: 1rem 0; text-wrap: balance; overflow-wrap: break-word; hyphens: auto; }
.feature-copy p { color: var(--muted); margin: 0; }
.feature-screen { margin-top: auto; padding: 1.5rem; display: grid; place-items: center; }
.feature-screen .device-shell { max-width: 260px; border-radius: 2.15rem; }
.feature-screen .phone-frame { border-width: 5px; border-radius: 1.95rem; }
.feature-explanation .feature-screen { background: var(--blue); }
.feature-adaptive .feature-screen { background: var(--mint); }
.feature-progress .feature-screen { background: var(--lavender); }
.exams-showcase { display: grid; grid-template-columns: 1.2fr .8fr; gap: 3rem; align-items: center; padding: clamp(1.25rem, 4vw, 3rem); background: var(--lavender); border-radius: 2.5rem; margin-block: 1rem 2rem; scroll-margin-top: 2rem; }
.exams-copy > p:last-child { color: var(--muted); font-size: 1.1rem; }
.exams-stage { display: grid; place-items: center; }
.exams-stage .device-shell { max-width: 280px; }
.ipad-showcase { display: grid; grid-template-columns: .8fr 1.4fr; gap: 3rem; align-items: center; padding: clamp(1.25rem, 4vw, 3rem); background: var(--mint); border-radius: 2.5rem; margin-block: 1rem 6rem; }
.tablet-frame { border: 8px solid #273046; border-radius: 1.5rem; overflow: hidden; background: #f2f2f7; box-shadow: 0 1.5rem 3rem -2rem #18223688; }
.clip-showcase { display: grid; grid-template-columns: 1.25fr .8fr; align-items: center; gap: 4rem; border-top: 1px solid var(--line); padding-block: 4rem 5rem; }
.clip-actions { display: flex; align-items: flex-start; flex-direction: column; gap: .6rem; margin-top: 1.75rem; }
.clip-copy .clip-note { font-size: .85rem; max-width: 30rem; }
.clip-actions .text-link { padding-block: .4rem; }
@media (prefers-color-scheme: dark) {
  .showcase { --lavender: #25233e; --mint: #192f2d; --blue: #1b2c49; --lavender-ink: #bfb3ff; --mint-ink: #8fdcb6; }
}
@media (max-width: 760px) {
  .showcase-hero, .exams-showcase, .ipad-showcase, .clip-showcase { grid-template-columns: minmax(0, 1fr); gap: 2rem; }
  .showcase-hero { padding-block: 1.5rem 2.5rem; }
  .hero-copy h1 { font-size: clamp(2.7rem, 8vw, 3.7rem); }
  .hero-stage { border-radius: 2rem; padding: 2rem 1rem; }
  .hero-stage .device-shell { max-width: 260px; }
  .feature-grid { grid-template-columns: minmax(0, 1fr); }
  .feature-copy { padding: 1.5rem; }
  .feature-screen { padding: 1.75rem; }
  .showcase-features { padding-block: 2rem 3rem; }
  .exams-showcase { margin-block: 0 1.5rem; border-radius: 2rem; }
  .exams-stage .device-shell { max-width: 260px; }
  .ipad-showcase { margin-block: 0 3rem; border-radius: 2rem; }
  .tablet-frame { border-width: 5px; border-radius: 1rem; }
  .clip-showcase { padding-block: 3rem; }
  .navigation { gap: .75rem; }
  .navigation > a { font-size: .8rem; }
}
@media (max-width: 380px) {
  .header { align-items: flex-start; flex-direction: column; }
  .hero-actions { align-items: flex-start; flex-direction: column; }
}

/* The journal shares the app showcase palette and uses a quieter reading layout. */
.journal { padding-block: 3rem 5rem; }
.journal-heading { max-width: 48rem; margin-bottom: 3rem; }
.journal-heading .intro, .article-heading .intro { margin-left: 0; max-width: 44rem; }
.journal-heading h1, .article-heading h1 { font-size: clamp(2.5rem, 5vw, 4rem); }
.post-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1.5rem; }
.post-card { position: relative; border: 1px solid var(--line); border-radius: 1.75rem; overflow: hidden; background: var(--surface); transition: border-color .2s, box-shadow .2s, transform .2s; }
.post-card:hover { border-color: var(--accent); box-shadow: 0 1.25rem 2.5rem -1.75rem #18223666; transform: translateY(-2px); }
.post-card-heading { padding: 1.75rem; background: var(--glow); }
.post-card-copy { padding: 1.75rem; }
.post-card-heading .eyebrow { color: var(--accent); margin-bottom: .6rem; }
.post-card :is(h2, h3) { font-size: 1.6rem; letter-spacing: -.035em; line-height: 1.25; margin: 0; text-wrap: balance; overflow-wrap: break-word; hyphens: auto; }
.post-card :is(h2, h3) a { color: var(--ink); text-decoration: none; }
.post-card :is(h2, h3) a::after { content: ""; position: absolute; inset: 0; border-radius: inherit; }
.post-card:hover :is(h2, h3) a { text-decoration: underline; text-decoration-thickness: 1px; }
.post-card p:not(.eyebrow) { color: var(--muted); margin: 0 0 1.25rem; }
.post-card time { color: var(--muted); font-size: .85rem; }
.blog-teaser { padding-block: 1rem 4rem; }
.blog-teaser > h2 { max-width: 45rem; }
.blog-teaser > .text-link { margin-top: 1.5rem; }
.journal-article { padding-block: 2.5rem 4rem; }
.article-heading { max-width: 54rem; margin: 0 auto 3rem; }
.article-heading > .eyebrow { margin-top: 2rem; }
.article-meta { font-size: .875rem; color: var(--muted); margin-top: 1.75rem; }
.exam-facts-caption { margin: 1.75rem 0 .75rem; color: var(--muted); font-size: .875rem; font-weight: 650; }
.exam-facts { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: clamp(.5rem, 2vw, 1rem); list-style: none; margin: 0; padding: 0; }
.exam-facts li { min-width: 0; }
.exam-facts a { display: flex; flex-direction: column; justify-content: space-between; gap: 1rem; height: 100%; padding: clamp(.7rem, 2.5vw, 1.5rem); background: var(--surface); border: 1px solid var(--line); border-radius: 1rem; text-decoration: none; }
.exam-facts a:hover { border-color: var(--accent); }
.fact-question { color: var(--muted); font-size: clamp(.8rem, 1.5vw, .95rem); line-height: 1.4; font-weight: 600; overflow-wrap: anywhere; hyphens: auto; }
.fact-value { display: flex; align-items: baseline; flex-wrap: wrap; gap: .3rem; color: var(--ink); font-size: clamp(1.6rem, 4vw, 3rem); letter-spacing: -.045em; line-height: 1.1; font-variant-numeric: tabular-nums; }
.fact-value small { color: var(--muted); font-size: .85rem; letter-spacing: 0; font-weight: 550; }
.article-layout { display: grid; grid-template-columns: 15rem minmax(0, 43rem); justify-content: center; gap: clamp(2rem, 5vw, 5rem); align-items: start; }
.article-toc { border-top: 2px solid var(--line); padding-top: 1rem; }
.article-toc p { font-weight: 650; margin: 0 0 .8rem; }
.article-toc ol { padding-left: 1.2rem; margin: 0; }
.article-toc li { padding-block: .5rem; font-size: .95rem; }
.article-prose { min-width: 0; font-size: 1.075rem; line-height: 1.8; }
.article-prose section { scroll-margin-top: 1.5rem; margin-bottom: 2.5rem; }
.article-prose h2 { font-size: 1.65rem; letter-spacing: -.035em; line-height: 1.25; margin: 0 0 1rem; }
.article-prose p { color: var(--muted); margin: 0 0 1.25rem; }
.article-prose ol { padding-left: 1.5rem; }
.article-prose li { padding-left: .3rem; margin-bottom: 1rem; color: var(--muted); }
.guide-table { width: 100%; table-layout: fixed; border-collapse: collapse; margin: 1.5rem 0; font-size: .95rem; line-height: 1.5; }
.guide-table caption { text-align: left; font-weight: 600; margin-bottom: .75rem; }
.guide-table th, .guide-table td { text-align: left; vertical-align: top; padding: .7rem .45rem; border-bottom: 1px solid var(--line); overflow-wrap: anywhere; }
.guide-table th { color: var(--ink); }
.guide-table thead th:nth-child(2) { width: 18%; }
.guide-table thead th:nth-child(2):last-child { width: 7.5rem; }
.guide-table :is(th, td) { hyphens: auto; }
.guide-table tbody th { font-weight: 500; }
.guide-table td { color: var(--muted); }
.category-table { border-collapse: separate; border-spacing: 0 .55rem; }
.category-table thead th { padding-block: .35rem; border: 0; font-size: .8rem; color: var(--muted); }
.category-table thead th:first-child { width: 46%; }
.category-table thead th:nth-child(2) { width: 17%; text-align: center; }
.category-table tbody :is(th, td) { background: var(--category-bg); border: 0; padding-block: 1rem; }
.category-table tbody th { border-left: 3px solid var(--category-ink); border-radius: .75rem 0 0 .75rem; font-weight: 600; }
.category-table tbody td:last-child { border-radius: 0 .75rem .75rem 0; font-variant-numeric: tabular-nums; }
.category-table tbody td { color: var(--ink); }
.category-table tbody td:nth-child(2) { text-align: center; }
.table-category { display: flex; align-items: flex-start; gap: .5rem; }
.table-category-icon { display: block; flex: 0 0 2rem; height: 2rem; }
.table-category-icon img { display: block; width: 2rem; height: 2rem; }
.table-count { display: inline-grid; place-items: center; min-width: 2rem; min-height: 2rem; padding: .15rem .3rem; border-radius: .6rem; background: var(--category-chip); color: var(--category-ink); font-weight: 750; font-variant-numeric: tabular-nums; }
.category-numeric { --category-ink: #a33c2d; --category-bg: #fce0d8; --category-chip: #faddd4; }
.category-verbal { --category-ink: #85520b; --category-bg: #fff0c4; --category-chip: #ffedc4; }
.category-logic, .category-deduction { --category-ink: #256347; --category-bg: #d9eee2; --category-chip: #d8eedf; }
.category-codes { --category-ink: #0b6878; --category-bg: #d5edf2; --category-chip: #d1edf2; }
.category-attention { --category-ink: #2451b8; --category-bg: #dfe9fb; --category-chip: #dce8ff; }
.category-spatial { --category-ink: #783aa3; --category-bg: #e9def6; --category-chip: #eedcff; }
.category-memory, .category-letters { --category-ink: #9b3553; --category-bg: #f8deea; --category-chip: #f9dbe4; }
.distribution-chart { margin: 1.75rem 0; padding: clamp(1rem, 3vw, 1.5rem); border: 1px solid var(--line); border-radius: 1rem; background: var(--surface); }
.distribution-chart figcaption { font-size: 1rem; font-weight: 650; color: var(--ink); }
.chart-content { display: flex; flex-wrap: wrap; align-items: center; gap: 1rem 1.5rem; margin: 1rem 0; }
.distribution-chart svg { display: block; flex: 1 1 15rem; min-width: 0; width: 100%; max-width: 18rem; height: auto; margin: 0 auto; overflow: visible; }
.chart-legend { display: grid; flex: 1 1 16rem; min-width: 0; gap: .6rem; list-style: none; padding: 0; margin: 0; }
.article-prose .chart-legend li { display: grid; grid-template-columns: .65rem 1.75rem minmax(0, 1fr) auto; align-items: center; gap: .45rem; margin: 0; padding: .2rem 0; }
.chart-legend-swatch { width: .65rem; height: .65rem; border: 1px solid var(--category-ink); border-radius: .2rem; background: var(--category-bg); }
.chart-legend-icon img { display: block; width: 1.75rem; height: 1.75rem; }
.chart-legend-label { color: var(--ink); font-size: .875rem; line-height: 1.4; }
.chart-legend-value { color: var(--muted); font-size: .8rem; font-variant-numeric: tabular-nums; white-space: nowrap; }
.chart-slice { fill: var(--category-bg); stroke: var(--category-ink); stroke-width: 1.5; }
.chart-segment-count { fill: var(--ink); font: 750 13px -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; }
.chart-total { fill: var(--ink); font: 750 36px -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; }
.chart-unit { fill: var(--muted); font: 500 13px -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; }
.distribution-chart > p { margin: 0; font-size: .875rem; }
.guide-formula { margin: 1.5rem 0; padding: clamp(1rem, 3vw, 1.5rem); border: 1px solid var(--line); border-radius: 1rem; background: var(--surface); }
.guide-formula figcaption { font-size: .875rem; font-weight: 650; color: var(--muted); }
.guide-formula math { margin: 1.5rem 0; font-size: clamp(1.6rem, 4vw, 2rem); color: var(--ink); }
.guide-formula dl { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: .75rem 1.25rem; margin: 0; font-size: .9rem; line-height: 1.5; }
.guide-formula dl > div { display: flex; align-items: baseline; gap: .65rem; }
.guide-formula dt { flex: 0 0 1rem; font-weight: 700; color: var(--ink); }
.guide-formula dd { margin: 0; color: var(--muted); }
@media (max-width: 480px) {
  .category-table { font-size: .875rem; }
  .category-table :is(th, td) { padding-inline: .35rem; }
  .table-category { gap: .35rem; }
  .guide-formula dl { grid-template-columns: minmax(0, 1fr); }
}
@media (prefers-color-scheme: dark) {
  .category-numeric { --category-ink: #ffb9a5; --category-bg: #533b39; --category-chip: #54332b; }
  .category-verbal { --category-ink: #f5ce8f; --category-bg: #514733; --category-chip: #4b3a20; }
  .category-logic, .category-deduction { --category-ink: #a2d9b4; --category-bg: #344b41; --category-chip: #254837; }
  .category-codes { --category-ink: #95d8e4; --category-bg: #304b52; --category-chip: #204650; }
  .category-attention { --category-ink: #adc9ff; --category-bg: #374760; --category-chip: #203b62; }
  .category-spatial { --category-ink: #dbb8f5; --category-bg: #493d5c; --category-chip: #432d5b; }
  .category-memory, .category-letters { --category-ink: #f6b5ca; --category-bg: #523b48; --category-chip: #533044; }
}
.worked-example { background: var(--surface); border: 1px solid var(--line); border-radius: 1.5rem; padding: clamp(1rem, 3vw, 2rem); margin-top: 1.5rem; }
.worked-example .eyebrow { color: var(--accent); }
.worked-example .example-display { border-radius: 1rem; background: var(--glow); color: var(--ink); padding: 1.5rem .75rem; font: 650 clamp(1rem, 3vw, 1.75rem) ui-monospace, monospace; text-align: center; }
.worked-example .example-multiline { white-space: pre; text-align: left; width: fit-content; max-width: 100%; margin-inline: auto; line-height: 1.5; }
/* Original countermodels: membership, seal status and rejected answers remain
   explicit in text; colour and the small inline vectors are supplementary. */
.box-model-options { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: .5rem; list-style: none; padding: 0; margin: 1.25rem 0; }
.article-prose .box-model-options li { display: flex; align-items: baseline; gap: .5rem; margin: 0; padding: .65rem .75rem; border: 1px solid var(--line); border-radius: .75rem; font-size: .85rem; line-height: 1.4; }
.box-model-options b { color: var(--ink); }
.box-models { margin: 1.5rem 0 0; }
.box-models > figcaption { color: var(--ink); font-size: 1rem; font-weight: 650; margin-bottom: 1rem; }
.box-model-cases { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 15rem), 1fr)); gap: 1rem; }
.article-prose .box-model-case { min-width: 0; border: 1px solid var(--line); border-radius: 1rem; padding: 1rem; background: var(--bg); margin-bottom: 0; }
.box-model-case > header { display: flex; align-items: center; gap: .65rem; min-height: 3rem; margin-bottom: 1rem; }
.box-model-case h3, .box-model-result h3 { color: var(--ink); font-size: 1.05rem; letter-spacing: -.02em; line-height: 1.35; margin: 0; }
.box-model-number { display: grid; place-items: center; flex: 0 0 2rem; height: 2rem; border-radius: 50%; background: var(--surface); color: var(--ink); font-weight: 700; }
.box-model-scene { --box-face: #c7ddfa; --box-top: #e2edff; --box-stroke: #5277a8; --box-ink: #203e65; padding: .65rem; border: 1px solid #bed2ed; border-radius: .9rem; background: #eff5ff; }
.box-model-layout { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); align-items: stretch; gap: .5rem; margin-top: .65rem; }
.box-model-tray, .box-model-outside { min-width: 0; padding: .5rem .2rem; border: 1px solid transparent; border-radius: .65rem; }
.box-model-tray { border: 2px dashed var(--box-stroke); background: var(--surface); }
.article-prose .box-model-group { color: var(--box-ink); font-size: .75rem; font-weight: 550; line-height: 1.35; text-align: center; margin: 0; min-height: 2.1em; overflow-wrap: anywhere; }
.box-model-group b { font-weight: 750; }
.box-model-object { text-align: center; margin-top: .35rem; }
.box-model-art { position: relative; width: 4rem; height: 4rem; margin-inline: auto; }
.box-model-art svg { display: block; width: 100%; height: auto; }
.box-model-face { fill: var(--box-face); stroke: var(--box-stroke); stroke-width: 1.5; stroke-linejoin: round; }
.box-model-top { fill: var(--box-top); stroke: var(--box-stroke); stroke-width: 1.5; stroke-linejoin: round; }
.box-model-edge { fill: none; stroke: var(--box-stroke); stroke-width: 1.5; }
.box-model-art text { fill: var(--box-ink); font: 700 15px system-ui, sans-serif; }
.box-model-stamp { position: absolute; top: .2rem; right: -.3rem; padding: .1rem .3rem; border: 1px solid var(--success); border-radius: .4rem; background: var(--success-bg); color: var(--success); font-size: .65rem; font-weight: 750; line-height: 1.3; }
.article-prose .box-model-status { display: grid; color: var(--box-ink); font-size: .75rem; line-height: 1.35; margin: .2rem 0 0; }
.box-model-status strong { font-size: .85rem; }
.article-prose .box-model-valid { color: var(--success); font-size: .8rem; line-height: 1.4; margin: 1rem 0 .5rem; }
.article-prose .box-model-rejected { display: flex; flex-wrap: wrap; align-items: center; gap: .4rem; color: var(--ink); font-size: .85rem; font-weight: 600; margin: .5rem 0; }
.box-model-rejected > span { padding: .15rem .5rem; border-radius: .4rem; background: var(--danger-bg); color: var(--danger); white-space: nowrap; }
.article-prose .box-model-reason { color: var(--muted); font-size: .9rem; line-height: 1.6; margin: .75rem 0 0; }
.box-model-result { display: grid; grid-template-columns: auto minmax(0, 1fr); gap: .75rem; align-items: center; padding: 1.25rem; border: 1px solid var(--line); border-radius: 1rem; background: var(--success-bg); margin-top: 1rem; }
.box-model-answer { display: grid; place-items: center; width: 2.75rem; height: 2.75rem; border-radius: .75rem; background: var(--surface); color: var(--success); font-size: 1.5rem; font-weight: 750; }
.article-prose .box-model-result-label { color: var(--muted); font-size: .8rem; line-height: 1.4; margin: .25rem 0 0; }
.article-prose .box-model-result > p { grid-column: 1 / -1; color: var(--ink); font-size: .95rem; line-height: 1.6; margin: 0; }
@media (prefers-color-scheme: dark) {
  .box-model-scene { --box-face: #29476e; --box-top: #3c5e88; --box-stroke: #93b6e4; --box-ink: #dbeaff; background: #14243b; border-color: #3c5a80; }
}
.example-figure { margin: 1.5rem 0; }
.example-figure figcaption { color: var(--ink); font-size: 1rem; line-height: 1.6; }
.article-practice { padding-top: 2rem; border-top: 1px solid var(--line); }
.article-practice .text-link { display: flex; }
.article-practice .app-store-badge { margin-top: .5rem; }
.related-posts { margin-top: 4rem; padding-top: 2rem; border-top: 1px solid var(--line); }
.related-posts > h2 { font-size: 2rem; letter-spacing: -.04em; }
@media (max-width: 760px) {
  .journal { padding-block: 2rem 3rem; }
  .post-grid, .article-layout { grid-template-columns: minmax(0, 1fr); }
  .article-layout { gap: 2rem; }
  .article-heading { margin-bottom: 2rem; }
  .article-prose { font-size: 1rem; }
  .post-card-heading, .post-card-copy { padding: 1.5rem; }
  .navigation { column-gap: 1rem; }
}
@media (prefers-reduced-motion: reduce) {
  .post-card { transition: none; }
  .post-card:hover { transform: none; }
}

.brand-button { display: inline-flex; justify-content: center; align-items: center; gap: .65rem; min-height: 44px; min-width: 160px; max-width: 100%; padding: .65rem 1rem; border-radius: .5rem; border: 1px solid #ffffff45; background: linear-gradient(145deg, #0073dc, #005edb); color: #fff; font-size: 1rem; font-weight: 700; line-height: 1.2; text-decoration: none; box-shadow: inset 0 1px 0 #ffffff30; }
.brand-button:hover { background: linear-gradient(145deg, #006bd0, #0051bf); }
.domino-preview { padding: 1.5rem; background: var(--surface); border: 1px solid var(--line); border-radius: 2rem; }
.domino-preview h3 { font-size: 1.3rem; line-height: 1.4; text-align: center; margin: 0; }
.domino-preview .domino-ring { margin-block: 1rem; }
.domino-preview-options { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); list-style: none; padding: 0; gap: .5rem; margin: 0; }
.domino-preview-options li { display: grid; justify-items: center; border: 1px solid var(--line); border-radius: .75rem; padding: .5rem; }
.domino-preview-options span { justify-self: start; font-size: .8rem; color: var(--muted); }
.domino-preview-options svg { width: 100%; max-width: 50px; height: auto; }
#app-clip { scroll-margin-top: 2rem; }

/* Skill areas, questions and the closing call to action. */
.skills { padding-block: 1rem 5rem; scroll-margin-top: 2rem; }
.skill-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1.25rem; list-style: none; margin: 0; padding: 0; }
.skill-card { border: 1px solid var(--line); border-radius: 1.75rem; background: var(--surface); padding: 1.75rem; }
.skill-icon { display: grid; place-items: center; width: 3rem; height: 3rem; margin-bottom: 1.25rem; border-radius: .9rem; background: var(--category-bg); }
.skill-icon img { display: block; width: 3rem; height: 3rem; }
.skill-card h3 { font-size: 1.3rem; line-height: 1.25; letter-spacing: -.03em; margin: 0 0 .6rem; }
.skill-card p { color: var(--muted); margin: 0; }
.faq { display: grid; grid-template-columns: minmax(0, .75fr) minmax(0, 1.4fr); gap: clamp(2rem, 5vw, 5rem); align-items: start; border-top: 1px solid var(--line); padding-block: 4rem; scroll-margin-top: 2rem; }
.faq-list { border-top: 1px solid var(--line); }
.faq-list details { border-bottom: 1px solid var(--line); }
.faq-list summary { display: flex; justify-content: space-between; align-items: center; gap: 1.5rem; padding-block: 1.25rem; cursor: pointer; list-style: none; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: "+"; content: "+" / ""; flex: none; display: grid; place-items: center; width: 2rem; height: 2rem; border-radius: 50%; background: var(--glow); color: var(--accent); font-size: 1.35rem; line-height: 1; transition: transform .2s ease; }
.faq-list details[open] summary::after { transform: rotate(45deg); }
.faq-list summary:hover h3 { color: var(--accent); }
.faq-list h3 { font-size: 1.15rem; line-height: 1.4; letter-spacing: -.02em; margin: 0; }
.faq-list details p { color: var(--muted); margin: -.25rem 0 1.5rem; max-width: 42rem; }
.cta-band { display: grid; justify-items: center; text-align: center; margin-block: 1rem 2rem; padding: clamp(2.5rem, 6vw, 4.5rem) clamp(1.25rem, 4vw, 3rem); border-radius: 2.5rem; background: linear-gradient(160deg, var(--blue), var(--lavender)); }
.cta-band .app-icon { width: 4.5rem; height: 4.5rem; margin: 0 0 1.5rem; }
.cta-band h2 { max-width: 36rem; }
.cta-band p { color: var(--muted); font-size: 1.1rem; max-width: 34rem; margin: 0; }
.cta-band .app-store-badge { margin-top: 1.75rem; }
.cta-band .app-store-badge img { width: auto; height: 48px; }
@media (max-width: 1000px) {
  .skill-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 760px) {
  .skills { padding-block: 0 3rem; }
  .skill-grid, .faq, .footer-main { grid-template-columns: minmax(0, 1fr); }
  .skill-card { padding: 1.5rem; }
  .faq { gap: 1.5rem; padding-block: 3rem; }
  .cta-band { border-radius: 2rem; }
  .footer-main { gap: 2rem; }
}
@media (prefers-reduced-motion: reduce) {
  .faq-list summary::after { transition: none; }
}

/* Links from an article section to the guide that covers it in depth. */
.guide-links { display: grid; gap: .6rem; list-style: none; padding: 0; margin: 1.25rem 0 0; }
.article-prose .guide-links li { margin: 0; padding: 0; }
.guide-links a { display: flex; align-items: center; gap: 1rem; padding: .8rem 1.1rem; border: 1px solid var(--line); border-radius: 1rem; background: var(--surface); color: var(--ink); font-weight: 600; line-height: 1.35; text-decoration: none; }
.guide-links a::after { content: "→"; content: "→" / ""; margin-left: auto; color: var(--accent); }
.guide-links a:hover { border-color: var(--accent); }

/* Native disclosure keeps the language selector usable without JavaScript. */
.language-switch { position: relative; font-size: .875rem; }
.language-switch summary { cursor: pointer; color: var(--muted); padding-block: .7rem; line-height: 1.4; list-style: none; }
.language-switch summary::-webkit-details-marker { display: none; }
.language-switch summary:hover { color: var(--accent); }
.language-switch ul { position: absolute; right: 0; top: 100%; z-index: 5; min-width: 12rem; max-width: calc(100vw - 2.5rem); margin: 0; padding: .5rem; list-style: none; border: 1px solid var(--line); border-radius: .75rem; background: var(--surface); box-shadow: 0 .5rem 1.5rem #18223622; }
.language-switch a { display: block; padding: .6rem .75rem; text-decoration: none; }
.language-switch a[aria-current="page"] { color: var(--ink); font-weight: 650; }
.language-switch a:hover { background: var(--glow); border-radius: .5rem; }
.navigation { flex-wrap: wrap; }
@media (max-width: 760px) {
  .header { flex-wrap: wrap; padding-block: 1rem; }
  .navigation { gap: .4rem .85rem; }
  .language-switch { font-size: .8rem; }
}