/* Learning pages use the existing RekenZorg typefaces and colours. */
html { scroll-behavior: auto; }
.learning-wrap, .phone-transfer, .formula-layout, .formula-hero { box-sizing: border-box; }
.learning-wrap *, .phone-transfer *, .formula-layout *, .formula-hero * { box-sizing: border-box; }
[hidden] { display: none !important; }
:where(a, button, summary, input, select):focus-visible { outline: 3px solid #087e87; outline-offset: 4px; }
:where(.formula-sheet, .route-guide, .method-sheet, #formules, #online-oefentoets) { scroll-margin-top: 105px; }
.learn-button { display: inline-flex; align-items: center; justify-content: center; padding: 13px 21px; min-height: 48px; border: 1px solid #145f68; border-radius: 8px; background: #145f68; color: #fff; font: 700 1rem/1.4 'Source Sans 3', sans-serif; text-decoration: none; text-align: center; cursor: pointer; }
.learn-button:hover { background: #0b424b; color: #fff; }
.learn-button.light { background: #fff; color: #14515b; border-color: #b3c7c6; }
.learn-button.light:hover { background: #edf5f1; }
.learning-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.learning-note, .quiz-note, .learning-source { font-size: .94rem; color: #47646a; }
.learning-wrap { max-width: 1120px; margin: 48px auto; padding: 0 28px; }
.quiz-shell { border: 1px solid #bdceca; border-top: 5px solid #157880; background: #fff; border-radius: 12px; padding: 38px; max-width: 840px; margin: 0 auto; scroll-margin-top: 100px; }
.quiz-shell h2 { font-size: clamp(1.7rem, 3vw, 2.4rem); margin: 10px 0 20px; color: #103c43; }
.quiz-shell p { margin: 12px 0; line-height: 1.65; }
.quiz-shell label { display: block; font-weight: 700; margin: 24px 0 8px; }
.quiz-shell input, .quiz-shell select { display: block; width: 100%; max-width: 400px; min-height: 52px; border: 1px solid #647f81; border-radius: 6px; padding: 10px 14px; color: #123b42; background: #fff; font: inherit; font-size: 1.1rem; margin-bottom: 18px; }
.quiz-shell input[aria-invalid="true"] { border-color: #9c3f24; }
.quiz-shell input[readonly] { background: #f3f6f4; }
.quiz-number-field { display: flex; align-items: center; gap: 12px; max-width: 400px; margin-bottom: 18px; }
.quiz-number-field input { min-width: 0; flex: 1; margin-bottom: 0; }
.quiz-number-field > span { flex-shrink: 0; color: #174951; font-weight: 700; }
.quiz-progress { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; font-size: .9rem; font-weight: 600; color: #4d656b; }
.quiz-shell progress { appearance: none; display: block; width: 100%; height: 6px; margin: 15px 0 30px; border: 0; background: #e7eeeb; accent-color: #167781; }
.quiz-shell progress::-webkit-progress-bar { background: #e7eeeb; }
.quiz-shell progress::-webkit-progress-value { background: #167781; }
.quiz-question { font-size: 1.2rem; }
.quiz-feedback { padding: 20px; border-left: 4px solid #34795f; background: #edf7ef; margin: 22px 0; }
.quiz-feedback.is-incorrect { background: #fff4e8; border-color: #a86323; }
.quiz-feedback p { margin-bottom: 0; }
.quiz-recommendations { padding: 0 0 0 24px; margin: 20px 0; }
.quiz-recommendations li { padding: 6px 0; }
.worked-example { border-top: 1px solid #dbe5de; margin-top: 20px; }
.worked-example summary { cursor: pointer; color: #155e65; font-weight: 700; padding: 15px 0; min-height: 48px; }
.worked-example > div { padding: 0 0 20px; line-height: 1.7; }
.worked-example > div p { margin: 12px 0 0; color: #496168; }
.example .worked-example { margin-top: 12px; }
.topic-explanation h3 { margin: 24px 0 12px; font-size: 1.3rem; }
.topic-explanation ol, .topic-explanation ul { padding-left: 24px; }
.topic-explanation li { margin: 12px 0; }
.topic-explanation p { margin: 14px 0; }
.download-choices { display: grid; gap: 24px; }
.download-choices section + section { border-top: 1px solid #cededa; padding-top: 16px; }
.phone-transfer { max-width: 1120px; margin: 48px auto 64px; padding: 36px; background: #edf3ed; border: 1px solid #d1ded5; border-radius: 12px; display: grid; grid-template-columns: 1fr auto; align-items: center; gap: 48px; color: #103b42; text-align: left; }
.phone-transfer .section-kicker { color: #366663; margin: 0 0 12px; }
.phone-transfer h2 { color: #103b42; font-size: 2rem; margin: 0 0 16px; }
.phone-transfer p { margin: 0; max-width: 440px; line-height: 1.65; }
.qr-stores { display: flex; gap: 20px; }
.phone-transfer { scroll-margin-top: 100px; }
.qr-store { display: flex; flex-direction: column; align-items: center; color: #174951; text-decoration: none; font-size: .94rem; }
.qr-store img { background: white; width: 136px; height: 136px; border-radius: 6px; margin-bottom: 12px; }
.qr-store span { text-decoration: underline; text-underline-offset: 3px; margin-top: 3px; }
.formula-page { background: #f7f8f3; color: #173e43; }
.formula-page .site-nav { background: #fffef9; backdrop-filter: none; }
.formula-page .breadcrumb { background: #fffef9; color: #516568; font-size: .8rem; }
.formula-hero { display: grid; grid-template-columns: minmax(0,1.5fr) minmax(260px, .8fr); align-items: center; gap: 64px; max-width: 1200px; margin: 0 auto; padding: 64px 40px 58px; }
.formula-hero .section-kicker { color: #286b6b; }
.formula-hero h1 { font-size: clamp(2.6rem, 4.3vw, 4rem); line-height: 1.13; color: #113a41; letter-spacing: -.025em; margin: 16px 0 24px; font-weight: 550; }
.formula-hero h1 em { font-style: normal; color: #327b79; }
.formula-lead { font-size: 1.2rem; line-height: 1.65; max-width: 570px; color: #426066; }
.hero-footnote { font-size: .9rem; color: #536c6a; margin-top: 17px; }
.formula-preview { background: #e3eee6; border: 1px solid #c7d9cd; border-radius: 12px; padding: 30px; }
.formula-preview > p { font-size: 1.14rem; line-height: 1.6; margin: 20px 0 30px; }
.preview-equation { display: flex; align-items: center; justify-content: space-between; gap: 12px; color: #144e53; }
.preview-equation > strong { font-size: 3.5rem; font-weight: 550; font-family: Fraunces, Georgia, serif; }
.preview-equation small { font: 500 1.3rem 'Source Sans 3', sans-serif; }
.preview-caption { display: block; font-size: .9rem; margin-top: 28px; border-top: 1px solid #bccfc2; padding-top: 16px; }
.fraction { display: inline-flex; flex-direction: column; align-items: center; text-align: center; line-height: 1.5; }
.fraction > span:first-child { border-bottom: 1.5px solid currentColor; padding: 0 9px 6px; }
.fraction > span:last-child { padding: 6px 9px 0; }
.formula-layout { max-width: 1200px; margin: 0 auto; padding: 10px 40px 64px; display: grid; grid-template-columns: 210px minmax(0, 1fr); gap: 48px; }
.formula-nav { position: sticky; top: 94px; align-self: start; display: flex; flex-direction: column; border-top: 2px solid #1c565a; padding-top: 20px; }
.formula-nav > strong { font-size: .95rem; margin-bottom: 14px; }
.formula-nav a { padding: 9px 0; text-decoration: none; font-size: .96rem; color: #456264; }
.formula-nav a:hover { color: #0d5b61; text-decoration: underline; }
.formula-nav a span { font-size: .74rem; color: #64817e; margin-right: 12px; }
.formula-body h2 { font-size: clamp(1.7rem, 3vw, 2.25rem); font-weight: 550; line-height: 1.2; margin: 0 0 20px; }
.route-guide { padding-bottom: 36px; border-bottom: 1px solid #cbd9d0; margin-bottom: 40px; }
.route-guide .section-kicker { color: #386863; }
.route-options { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.route-options a { border: 1px solid #cfddd5; padding: 16px 18px; border-radius: 7px; background: #fffefb; font-weight: 700; text-decoration: none; }
.route-options a:hover { border-color: #387e79; }
.route-options a span { display: block; color: #54716c; font-size: .88rem; font-weight: 400; margin-top: 6px; }
.formula-section-heading p { margin: -8px 0 25px; color: #4e6968; }
.formula-sheet { background: #fffefb; border: 1px solid #d1ddd4; border-radius: 9px; padding: 28px 32px; margin: 0 0 20px; }
.formula-title { display: flex; gap: 18px; align-items: center; margin-bottom: 20px; }
.formula-number { font: 500 1.45rem Fraunces, Georgia, serif; color: #40817a; background: #eef4ee; border-radius: 50%; width: 45px; height: 45px; display: grid; place-items: center; flex: 0 0 auto; }
.formula-level { color: #5b746e; font-size: .8rem; margin: 0 0 4px; }
.formula-title h3 { font-size: 1.65rem; font-weight: 550; margin: 0; line-height: 1.2; }
.formula-sheet > p { color: #486460; margin-bottom: 18px; }
.formula-equation { display: flex; align-items: center; justify-content: center; gap: 20px; padding: 24px 16px; background: #eff5f0; border-radius: 5px; font-size: 1rem; color: #154f53; }
.formula-equation > strong { font-size: .95rem; font-weight: 600; }
.formula-equation .expression { max-width: 400px; }
.topic-link { display: inline-block; color: #256b6b; font-size: .94rem; text-underline-offset: 4px; margin-top: 5px; }
.method-sheet { padding: 36px 0; }
.method-sheet p { margin: 16px 0; }
.method-sheet ol { padding-left: 25px; margin: 20px 0; }
.method-sheet li { margin: 12px 0; }
.method-sheet h3 { margin-top: 28px; font-size: 1.5rem; }
.worksheet-panel { background: #e3eee6; border-radius: 10px; padding: 30px; margin: 15px 0 25px; }
.worksheet-panel .section-kicker { color: #316762; }
.formula-page .faq-section, .formula-page .cluster-section { max-width: 1120px; margin-left: auto; margin-right: auto; }
.formula-page .download-band { display: none; }
.home-learning { max-width: 1180px; padding: 64px 30px 16px; margin: 0 auto; color: #123e43; }
.home-learning > .section-kicker { color: #2b706e; }
.home-learning > h2 { font-size: clamp(2rem, 3vw, 2.7rem); margin: 12px 0 28px; }
.home-learning-links { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.home-learning-links > a { background: #fffefa; border: 1px solid #ccdcd4; border-radius: 10px; padding: 26px; text-decoration: none; }
.home-learning-links > a:hover { border-color: #237b77; }
.home-learning-links span { color: #5c7771; font-size: .83rem; }
.home-learning-links h3 { margin: 18px 0 14px; font-size: 1.6rem; }
.home-learning-links p { margin: 0 0 22px; color: #49666a; line-height: 1.65; }
.home-learning-links strong { color: #226965; font-size: .95rem; }
@media (max-width: 1050px) {
  .formula-hero { gap: 30px; padding: 48px 28px; }
  .formula-layout { padding: 8px 28px 48px; gap: 28px; grid-template-columns: 175px minmax(0,1fr); }
  .formula-sheet { padding: 24px; }
  .formula-equation { flex-wrap: wrap; gap: 12px; }
  .phone-transfer { margin: 35px 28px; gap: 25px; }
}
@media (max-width: 760px) {
  .footer-links { flex-wrap: wrap; justify-content: center; gap: 12px 18px; }
  .qr-desktop-instruction { display: none; }
  .home-learning { padding: 36px 22px 8px; }
  .home-learning-links { grid-template-columns: 1fr; }
  .formula-hero { grid-template-columns: 1fr; padding: 36px 22px; gap: 30px; }
  .formula-preview { padding: 23px; }
  .formula-preview > p { margin: 12px 0 20px; }
  .formula-layout { display: block; padding: 0 22px 35px; }
  .formula-nav { position: static; display: flex; flex-direction: row; flex-wrap: wrap; gap: 0 18px; padding: 15px 0 24px; margin-bottom: 25px; }
  .formula-nav > strong { width: 100%; margin-bottom: 4px; }
  .formula-nav a { font-size: .88rem; padding: 6px 0; }
  .formula-nav a span { display: none; }
  .route-options { grid-template-columns: 1fr; }
  .formula-sheet { padding: 22px 18px; }
  .formula-title { gap: 12px; }
  .formula-title h3 { font-size: 1.5rem; }
  .formula-equation { font-size: .9rem; padding: 20px 10px; }
  .formula-equation > strong { width: 100%; text-align: center; }
  .formula-equation > span:not(.fraction):not(.expression) { display: none; }
  .formula-equation .expression { text-align: center; overflow-wrap: anywhere; }
  .fraction { max-width: 100%; }
  .worksheet-panel { padding: 24px 20px; }
  .learning-wrap { padding: 0 20px; margin: 30px auto; }
  .quiz-shell { padding: 25px 20px; }
  .quiz-question { font-size: 1.1rem; }
  .learning-actions { flex-direction: column; align-items: stretch; }
  .phone-transfer { display: block; padding: 28px 22px; margin: 30px 20px; }
  .phone-transfer h2 { font-size: 1.8rem; }
  .qr-stores { margin-top: 22px; flex-wrap: wrap; gap: 16px; }
  .qr-store img { display: none; }
  .qr-store { flex: 1 1 120px; padding: 14px 10px; border: 1px solid #abc6bd; border-radius: 7px; background: #fff; }
  .hero-actions .learn-button { width: 100%; }
}
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation: none !important; transition: none !important; } }
@media print {
  .site-nav, .breadcrumb, .formula-nav, .hero-actions, .learning-actions, .phone-transfer, .download-band, footer { display: none !important; }
  .formula-layout, .formula-hero { display: block; padding: 0; }
  .formula-preview { display: none; }
  .formula-sheet { break-inside: avoid; }
}