/* Shared styles for practice tests, math lessons and the exam simulator.
   The home page (index.html) carries its own inline styles with the same tokens. */
:root {
  --ink: #15180f;
  --olive-950: #12160e;
  --olive-900: #1b2116;
  --olive-800: #252d1d;
  --olive-700: #354129;
  --olive-600: #4a5939;
  --khaki-50: #faf7f0;
  --khaki-100: #f3eee2;
  --khaki-200: #e8dfcb;
  --khaki-300: #d6c9ab;
  --gold: #e3a823;
  --gold-light: #f4c95a;
  --gold-dark: #b9840f;
  --text: #1d2017;
  --muted: #5c6050;
  --on-dark: #f3eee2;
  --on-dark-muted: #b7b8a6;
  --ok: #1f8a4c;
  --ok-bg: #e6f5ec;
  --bad: #c43b2f;
  --bad-bg: #fbeae8;
  --radius: 16px;
  --shadow-sm: 0 1px 2px rgba(18, 22, 14, .06), 0 6px 18px -8px rgba(18, 22, 14, .18);
  --shadow-lg: 0 30px 60px -20px rgba(18, 22, 14, .45), 0 12px 24px -12px rgba(18, 22, 14, .35);
  --display: "Barlow Condensed", "Arial Narrow", system-ui, sans-serif;
  --body: "Barlow", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --wrap: 1160px;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; font-family: var(--body); font-size: 17px; line-height: 1.6;
  color: var(--text); background: var(--khaki-50); -webkit-font-smoothing: antialiased; overflow-x: hidden;
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; }
h1, h2, h3, h4 { font-family: var(--display); line-height: 1.05; margin: 0; }
p { margin: 0; }
:focus-visible { outline: 3px solid var(--gold); outline-offset: 3px; border-radius: 6px; }
.wrap { width: 100%; max-width: var(--wrap); margin: 0 auto; padding: 0 20px; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 16px; z-index: 100; background: var(--gold); color: var(--ink); padding: 8px 14px; border-radius: 8px; }
.katex { font-size: 1.08em; }
.q-text .katex, .choice .katex { font-size: 1.18em; }

/* ---------- Buttons & badge ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  font-family: var(--display); font-weight: 700; font-size: 17px; letter-spacing: .06em; text-transform: uppercase;
  text-decoration: none; border-radius: 10px; padding: 11px 20px; border: 0; cursor: pointer;
  background: var(--gold); color: var(--ink); transition: background .15s, transform .15s;
}
.btn:hover { background: var(--gold-light); transform: translateY(-1px); }
.btn.dark { background: var(--olive-800); color: var(--on-dark); }
.btn.dark:hover { background: var(--olive-700); }
.btn.ghost { background: transparent; color: var(--olive-800); box-shadow: inset 0 0 0 1.5px var(--khaki-300); }
.btn.ghost:hover { background: var(--khaki-100); }
.btn.light-ghost { background: transparent; color: var(--on-dark); box-shadow: inset 0 0 0 1.5px rgba(243, 238, 226, .35); }
.btn.light-ghost:hover { background: rgba(243, 238, 226, .08); }
.btn:disabled { opacity: .5; cursor: default; transform: none; }
.btn svg { width: 18px; height: 18px; }
.badge {
  display: inline-flex; align-items: center; gap: 10px; height: 54px; padding: 0 18px 0 14px;
  background: #000; color: #fff; text-decoration: none; border: 1px solid #8e8e8e; border-radius: 12px;
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Helvetica Neue", Arial, sans-serif;
  transition: transform .15s ease; flex: none;
}
.badge:hover { transform: translateY(-2px); }
.badge svg { width: 26px; height: 26px; fill: #fff; margin-top: -3px; }
.badge span { display: flex; flex-direction: column; line-height: 1; }
.badge small { font-size: 11px; letter-spacing: .02em; }
.badge strong { font-size: 23px; font-weight: 600; letter-spacing: -.02em; margin-top: 3px; }

/* ---------- Nav ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(18, 22, 14, .92); backdrop-filter: saturate(140%) blur(12px); -webkit-backdrop-filter: saturate(140%) blur(12px);
  border-bottom: 1px solid rgba(243, 238, 226, .08);
}
.nav .wrap { display: flex; align-items: center; justify-content: space-between; height: 64px; gap: 16px; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--on-dark); }
.brand img { width: 34px; height: 34px; border-radius: 9px; }
.brand b { font-family: var(--display); font-size: 21px; font-weight: 800; letter-spacing: .03em; text-transform: uppercase; }
.brand b em { font-style: normal; color: var(--gold); }
.nav-links { display: flex; align-items: center; gap: 26px; }
.nav-links a:not(.btn) { color: var(--on-dark-muted); text-decoration: none; font-weight: 500; font-size: 15px; }
.nav-links a:not(.btn):hover, .nav-links a[aria-current="page"] { color: var(--on-dark); }
.nav-links a[aria-current="page"] { box-shadow: 0 2px 0 var(--gold); }
.nav-links .btn { padding: 8px 16px; font-size: 16px; }
.menu-btn { display: none; background: none; border: 0; color: var(--on-dark); padding: 8px; margin-right: -8px; cursor: pointer; }
.menu-btn svg { width: 26px; height: 26px; }

/* ---------- Page hero ---------- */
.page-hero {
  color: var(--on-dark);
  background:
    radial-gradient(800px 400px at 90% 0%, rgba(227, 168, 35, .18), transparent 60%),
    linear-gradient(180deg, var(--olive-950), var(--olive-900));
}
.page-hero .wrap { padding-top: 34px; padding-bottom: 48px; }
.crumbs { display: flex; flex-wrap: wrap; gap: 6px; list-style: none; margin: 0 0 22px; padding: 0; font-size: 14px; color: var(--on-dark-muted); }
.crumbs li + li::before { content: "/"; margin-right: 6px; opacity: .5; }
.crumbs a { text-decoration: none; }
.crumbs a:hover { color: var(--on-dark); text-decoration: underline; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 8px; font-family: var(--display); font-weight: 700; font-size: 15px;
  letter-spacing: .14em; text-transform: uppercase; color: var(--gold);
}
.page-hero h1 { font-size: clamp(38px, 5.6vw, 64px); font-weight: 800; text-transform: uppercase; margin-top: 10px; max-width: 900px; }
.page-hero .lead { margin-top: 14px; font-size: 18.5px; color: var(--on-dark-muted); max-width: 760px; }
.page-hero .lead b { color: var(--on-dark); font-weight: 600; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; }
.chip {
  display: inline-flex; align-items: center; gap: 6px; padding: 5px 12px; border-radius: 999px; font-size: 14px; font-weight: 600;
  background: rgba(243, 238, 226, .08); border: 1px solid rgba(243, 238, 226, .14); color: var(--on-dark);
}
.chip.gold { background: var(--gold); color: var(--ink); border-color: var(--gold); }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 26px; }

/* ---------- Layout ---------- */
.layout { display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: 36px; align-items: start; padding-top: 40px; padding-bottom: 80px; }
.layout.single { grid-template-columns: minmax(0, 1fr); max-width: 880px; }
.sidebar { position: sticky; top: 84px; display: grid; gap: 18px; }
.panel { background: #fff; border: 1px solid var(--khaki-200); border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow-sm); }
.panel h2, .panel h3 { font-size: 20px; font-weight: 700; text-transform: uppercase; letter-spacing: .02em; margin-bottom: 12px; }
.side-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 2px; max-height: 420px; overflow: auto; }
.side-list a { display: flex; justify-content: space-between; gap: 10px; padding: 7px 10px; border-radius: 8px; text-decoration: none; font-size: 15px; color: var(--text); }
.side-list a:hover { background: var(--khaki-100); }
.side-list a[aria-current="page"] { background: var(--olive-800); color: var(--on-dark); }
.side-list small { color: var(--muted); }
.side-list a[aria-current="page"] small { color: var(--on-dark-muted); }
.section { padding: 64px 0; }
.section-title { font-size: clamp(30px, 4vw, 42px); font-weight: 800; text-transform: uppercase; margin-bottom: 10px; }
.section-sub { color: var(--muted); max-width: 720px; margin-bottom: 28px; }
.prose p + p, .prose p + ul, .prose ul + p { margin-top: 12px; }
.prose ul { margin: 10px 0 0; padding-left: 22px; }
.prose li + li { margin-top: 4px; }

/* ---------- Cards / grids ---------- */
.grid { display: grid; gap: 16px; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); }
.card {
  position: relative; display: flex; flex-direction: column; gap: 6px; padding: 20px; border-radius: var(--radius);
  background: #fff; border: 1px solid var(--khaki-200); box-shadow: var(--shadow-sm); text-decoration: none; color: var(--text);
  transition: transform .15s, border-color .15s;
}
a.card:hover { transform: translateY(-2px); border-color: var(--khaki-300); }
.card h3 { font-size: 23px; font-weight: 700; text-transform: uppercase; letter-spacing: .01em; }
.card p { color: var(--muted); font-size: 15.5px; }
.card .meta { margin-top: auto; padding-top: 10px; font-size: 14px; color: var(--olive-600); font-weight: 600; }
.card .code {
  width: 48px; height: 48px; border-radius: 12px; display: grid; place-items: center; margin-bottom: 8px;
  font-family: var(--display); font-weight: 800; font-size: 21px; background: var(--khaki-100); color: var(--olive-700); border: 1px solid var(--khaki-200);
}
.card.afqt .code { background: var(--olive-800); color: var(--gold); border-color: var(--olive-800); }
.tag {
  position: absolute; top: 14px; right: 14px; font-family: var(--display); font-weight: 700; font-size: 12px; letter-spacing: .1em;
  background: var(--gold); color: var(--ink); padding: 2px 8px; border-radius: 6px;
}
.tag.muted { background: var(--khaki-100); color: var(--muted); }
.test-cards { display: grid; gap: 16px; grid-template-columns: repeat(3, 1fr); }
.test-card { background: var(--olive-900); color: var(--on-dark); border-color: var(--olive-900); }
.test-card h3 { color: var(--on-dark); }
.test-card p { color: var(--on-dark-muted); }
.test-card .meta { color: var(--gold); }
.set-list { display: grid; gap: 10px; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); list-style: none; padding: 0; margin: 0; }
.set-list a {
  display: flex; align-items: center; gap: 12px; padding: 14px 16px; border-radius: 12px; text-decoration: none;
  background: #fff; border: 1px solid var(--khaki-200); font-weight: 600;
}
.set-list a:hover { border-color: var(--khaki-300); background: var(--khaki-100); }
.set-list .num {
  width: 38px; height: 38px; border-radius: 10px; display: grid; place-items: center; flex: none;
  background: var(--olive-800); color: var(--gold); font-family: var(--display); font-size: 18px; font-weight: 800;
}
.set-list small { display: block; color: var(--muted); font-weight: 500; font-size: 13.5px; }
.tips { counter-reset: tip; list-style: none; padding: 0; margin: 0; display: grid; gap: 12px; }
.tips li { counter-increment: tip; display: grid; grid-template-columns: 34px 1fr; gap: 12px; }
.tips li::before {
  content: counter(tip); width: 34px; height: 34px; border-radius: 9px; display: grid; place-items: center;
  background: var(--khaki-100); color: var(--olive-700); font-family: var(--display); font-weight: 800; font-size: 18px;
}

/* ---------- App CTA ---------- */
.app-cta {
  display: flex; align-items: center; gap: 20px; padding: 24px; border-radius: var(--radius); margin: 36px 0 0;
  background: radial-gradient(500px 200px at 100% 0%, rgba(227, 168, 35, .22), transparent 70%), var(--olive-900);
  color: var(--on-dark);
}
.app-cta img { width: 64px; height: 64px; border-radius: 15px; flex: none; }
.app-cta div { flex: 1; min-width: 0; }
.app-cta h2 { font-size: 26px; font-weight: 800; text-transform: uppercase; }
.app-cta p { color: var(--on-dark-muted); font-size: 15.5px; margin-top: 4px; }
.sidebar .app-cta { flex-direction: column; align-items: flex-start; margin: 0; padding: 20px; }
.sidebar .app-cta h2 { font-size: 22px; }

/* ---------- Quiz (practice sets & lesson exercises) ---------- */
.quiz-bar {
  position: sticky; top: 64px; z-index: 10; display: flex; align-items: center; justify-content: space-between; gap: 12px;
  margin-bottom: 18px; padding: 10px 14px; border-radius: 12px; background: rgba(250, 247, 240, .95);
  backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); border: 1px solid var(--khaki-200); font-size: 15px;
}
.quiz-bar .progress { flex: 1; height: 8px; border-radius: 99px; background: var(--khaki-200); overflow: hidden; max-width: 260px; }
.quiz-bar .progress i { display: block; height: 100%; width: 0; background: var(--olive-700); transition: width .25s; }
.quiz-bar b { font-weight: 700; }
.linkish { background: none; border: 0; padding: 0; color: var(--olive-600); font: inherit; font-weight: 600; text-decoration: underline; cursor: pointer; }
.qlist { list-style: none; margin: 0; padding: 0; display: grid; gap: 18px; }
.q { background: #fff; border: 1px solid var(--khaki-200); border-radius: var(--radius); padding: 22px; box-shadow: var(--shadow-sm); scroll-margin-top: 140px; }
.q-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; margin-bottom: 10px; }
.q-num { font-family: var(--display); font-weight: 700; font-size: 16px; letter-spacing: .1em; text-transform: uppercase; color: var(--olive-600); }
.diff { font-size: 12.5px; font-weight: 700; letter-spacing: .04em; text-transform: uppercase; padding: 2px 9px; border-radius: 99px; }
.diff-easy { background: var(--ok-bg); color: var(--ok); }
.diff-medium { background: #fbf1d8; color: #9a6a00; }
.diff-hard { background: var(--bad-bg); color: var(--bad); }
.q-text { font-size: 17.5px; font-weight: 500; }
.q-text p + p { margin-top: 10px; }
.q-text ul { margin: 8px 0 0; padding-left: 22px; }
.choices { display: grid; gap: 8px; margin-top: 16px; }
.choices.two { grid-template-columns: 1fr 1fr; }
.choice {
  display: flex; align-items: center; gap: 12px; width: 100%; text-align: left; padding: 11px 14px; border-radius: 12px; cursor: pointer;
  background: var(--khaki-50); border: 1.5px solid var(--khaki-200); font: inherit; color: var(--text); transition: border-color .15s, background .15s;
}
.choice:hover:not(:disabled) { border-color: var(--olive-600); background: #fff; }
.choice b {
  width: 30px; height: 30px; border-radius: 8px; display: grid; place-items: center; flex: none;
  background: #fff; border: 1px solid var(--khaki-300); font-family: var(--display); font-size: 16px;
}
.choice:disabled { cursor: default; }
.choice.is-selected { border-color: var(--olive-700); background: #fff; box-shadow: inset 0 0 0 1px var(--olive-700); }
.choice.is-selected b { background: var(--olive-700); color: #fff; border-color: var(--olive-700); }
.choice.is-correct { border-color: var(--ok); background: var(--ok-bg); }
.choice.is-correct b { background: var(--ok); color: #fff; border-color: var(--ok); }
.choice.is-wrong { border-color: var(--bad); background: var(--bad-bg); }
.choice.is-wrong b { background: var(--bad); color: #fff; border-color: var(--bad); }
.explain { margin-top: 14px; border-top: 1px dashed var(--khaki-300); padding-top: 12px; }
.explain summary { cursor: pointer; font-weight: 600; color: var(--olive-600); font-size: 15px; }
.explain > div { margin-top: 10px; color: var(--text); font-size: 16px; }
.explain .answer-line { font-weight: 600; margin-bottom: 6px; }
.explain .verdict { font-weight: 700; margin-bottom: 4px; }
.explain .verdict.ok { color: var(--ok); }
.explain .verdict.bad { color: var(--bad); }
.quiz-result { margin-top: 24px; padding: 24px; border-radius: var(--radius); background: var(--olive-900); color: var(--on-dark); text-align: center; }
.quiz-result .score { font-family: var(--display); font-size: 64px; font-weight: 800; color: var(--gold); line-height: 1; }
.quiz-result p { color: var(--on-dark-muted); margin-top: 8px; }
.quiz-result .hero-actions { justify-content: center; }
.pager { display: flex; justify-content: space-between; gap: 12px; margin-top: 28px; flex-wrap: wrap; }
.pager a { display: flex; flex-direction: column; gap: 2px; padding: 14px 18px; border-radius: 12px; background: #fff; border: 1px solid var(--khaki-200); text-decoration: none; min-width: 200px; }
.pager a:hover { border-color: var(--khaki-300); }
.pager small { color: var(--muted); font-size: 13px; }
.pager b { font-weight: 600; }
.pager .next { margin-left: auto; text-align: right; }

/* ---------- Lessons ---------- */
.lesson { background: #fff; border: 1px solid var(--khaki-200); border-radius: var(--radius); padding: 28px; box-shadow: var(--shadow-sm); scroll-margin-top: 90px; }
.lesson + .lesson { margin-top: 22px; }
.lesson > h2 { font-size: clamp(26px, 3.4vw, 34px); font-weight: 800; text-transform: uppercase; }
.lesson h3 { font-size: 23px; font-weight: 700; margin-top: 22px; text-transform: uppercase; letter-spacing: .01em; }
.lesson h4 { font-size: 17px; font-weight: 700; letter-spacing: .12em; text-transform: uppercase; color: var(--olive-600); margin-bottom: 8px; }
.formula { margin-top: 14px; padding: 16px 18px; border-radius: 12px; background: var(--khaki-50); border: 1px solid var(--khaki-200); border-left: 4px solid var(--gold); overflow-x: auto; }
.formula p + p { margin-top: 6px; }
.tip { margin-top: 16px; padding: 14px 16px; border-radius: 12px; background: #fbf3dc; border: 1px solid #f0dca5; font-size: 16px; }
.tip > b { display: block; font-family: var(--display); letter-spacing: .1em; text-transform: uppercase; color: #8a6200; margin-bottom: 4px; }
.example { margin-top: 18px; padding: 18px; border-radius: 12px; background: var(--khaki-100); }
.exercises { margin-top: 22px; }
.exercises ol { list-style: none; padding: 0; margin: 0; display: grid; gap: 12px; }
.ex { padding: 16px; border-radius: 12px; border: 1px solid var(--khaki-200); background: var(--khaki-50); }
.ex .ex-n { font-family: var(--display); font-weight: 700; letter-spacing: .1em; text-transform: uppercase; color: var(--olive-600); font-size: 14px; }
.toc { list-style: none; margin: 18px 0 0; padding: 0; display: flex; flex-wrap: wrap; gap: 8px; }
.toc a { display: inline-block; padding: 6px 12px; border-radius: 99px; background: rgba(243, 238, 226, .08); border: 1px solid rgba(243, 238, 226, .16); text-decoration: none; font-size: 14.5px; }
.toc a:hover { background: rgba(243, 238, 226, .16); }
.course { margin-bottom: 26px; }
.course h2 { font-size: 30px; font-weight: 800; text-transform: uppercase; }
.course h2 a { text-decoration: none; }
.course h2 a:hover { text-decoration: underline; }
.course > p { color: var(--muted); margin: 4px 0 14px; }

/* ---------- Exam simulator ---------- */
.exam-app { min-height: 60vh; }
.exam-setup { display: grid; gap: 16px; grid-template-columns: repeat(auto-fill, minmax(210px, 1fr)); }
.exam-opt { text-align: left; cursor: pointer; font: inherit; }
.exam-opt.is-active { border-color: var(--olive-700); box-shadow: inset 0 0 0 2px var(--olive-700); }
.exam-opt select { margin-top: 10px; font: inherit; padding: 8px 10px; border-radius: 8px; border: 1px solid var(--khaki-300); background: #fff; width: 100%; }
.exam-controls { display: flex; flex-wrap: wrap; align-items: center; gap: 16px 28px; margin-top: 22px; padding: 18px 20px; border-radius: var(--radius); background: #fff; border: 1px solid var(--khaki-200); }
.exam-controls label { display: inline-flex; align-items: center; gap: 8px; font-weight: 500; cursor: pointer; }
.exam-controls input { width: 18px; height: 18px; accent-color: var(--olive-700); }
.exam-controls .btn { margin-left: auto; }
.exam-top {
  position: sticky; top: 64px; z-index: 10; display: flex; align-items: center; gap: 14px; flex-wrap: wrap;
  padding: 12px 16px; border-radius: 12px; background: var(--olive-900); color: var(--on-dark); margin-bottom: 16px;
}
.exam-top .part { font-weight: 600; }
.exam-top .timer { margin-left: auto; font-variant-numeric: tabular-nums; font-family: var(--display); font-size: 22px; font-weight: 700; color: var(--gold); }
.exam-top .progress { flex-basis: 100%; height: 6px; border-radius: 99px; background: rgba(243, 238, 226, .15); overflow: hidden; }
.exam-top .progress i { display: block; height: 100%; width: 0; background: var(--gold); transition: width .25s; }
.exam-nav { display: flex; gap: 10px; margin-top: 16px; flex-wrap: wrap; }
.exam-nav .spacer { flex: 1; }
.palette { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 22px; }
.palette button {
  width: 38px; height: 38px; border-radius: 9px; border: 1px solid var(--khaki-300); background: #fff; cursor: pointer;
  font: inherit; font-size: 14px; font-weight: 600; color: var(--text);
}
.palette button.done { background: var(--khaki-200); }
.palette button.ok { background: var(--ok-bg); border-color: var(--ok); color: var(--ok); }
.palette button.bad { background: var(--bad-bg); border-color: var(--bad); color: var(--bad); }
.palette button.cur { box-shadow: 0 0 0 2px var(--olive-800); }
.results-head { display: grid; grid-template-columns: auto 1fr; gap: 28px; align-items: center; padding: 28px; border-radius: var(--radius); background: var(--olive-900); color: var(--on-dark); }
.ring { width: 150px; height: 150px; border-radius: 50%; display: grid; place-items: center; background: conic-gradient(var(--gold) calc(var(--p) * 1%), rgba(243, 238, 226, .12) 0); }
.ring span { width: 118px; height: 118px; border-radius: 50%; background: var(--olive-900); display: grid; place-items: center; font-family: var(--display); font-size: 42px; font-weight: 800; }
.results-head h2 { font-size: 36px; font-weight: 800; text-transform: uppercase; }
.results-head p { color: var(--on-dark-muted); margin-top: 6px; }
.bars { display: grid; gap: 10px; margin-top: 22px; }
.bar { display: grid; grid-template-columns: 200px 1fr 70px; gap: 12px; align-items: center; font-size: 15px; }
.bar .track { height: 12px; border-radius: 99px; background: var(--khaki-200); overflow: hidden; }
.bar .track i { display: block; height: 100%; background: var(--olive-700); }
.bar b { text-align: right; font-variant-numeric: tabular-nums; }
.review-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin: 36px 0 14px; flex-wrap: wrap; }
.review-head h2 { font-size: 30px; font-weight: 800; text-transform: uppercase; }
.note { font-size: 14px; color: var(--muted); margin-top: 14px; }

/* ---------- "Get the app" prompt ---------- */
.app-prompt {
  border: 0; padding: 0; color: var(--on-dark); background: var(--olive-900);
  box-shadow: 0 40px 80px -20px rgba(0, 0, 0, .6); overflow: visible;
}
.app-prompt::backdrop { background: rgba(10, 12, 8, .62); backdrop-filter: blur(3px); -webkit-backdrop-filter: blur(3px); }
.app-prompt h2 { font-size: 30px; font-weight: 800; text-transform: uppercase; line-height: 1.02; }
.app-prompt p { color: var(--on-dark-muted); margin-top: 10px; font-size: 16px; }
.app-prompt .linkish { color: var(--on-dark-muted); }
.ap-close {
  position: absolute; top: 10px; right: 12px; width: 36px; height: 36px; border-radius: 50%; border: 0; cursor: pointer;
  background: rgba(243, 238, 226, .08); color: var(--on-dark); font-size: 24px; line-height: 1;
}
.ap-close:hover { background: rgba(243, 238, 226, .16); }
.ap-points { list-style: none; padding: 0; margin: 16px 0 0; display: grid; gap: 8px; font-size: 15px; }
.ap-points li { display: flex; gap: 10px; align-items: flex-start; }
.ap-points li::before { content: "★"; color: var(--gold); flex: none; }
/* computer: QR first */
.app-prompt.is-qr {
  width: min(760px, calc(100vw - 32px)); border-radius: 22px; padding: 30px;
  display: grid; grid-template-columns: 240px 1fr; gap: 30px; align-items: center;
  background: radial-gradient(500px 260px at 100% 0%, rgba(227, 168, 35, .2), transparent 70%), var(--olive-900);
}
.app-prompt.is-qr:not([open]) { display: none; }
.ap-qr { background: #fff; border-radius: 18px; padding: 18px 18px 12px; text-align: center; box-shadow: 0 0 0 6px rgba(227, 168, 35, .35); }
.ap-qr img { width: 100%; height: auto; }
.ap-qr span { display: block; margin-top: 8px; font-size: 13px; font-weight: 600; color: var(--olive-700); }
.ap-body .eyebrow { margin-bottom: 8px; }
.ap-alt { font-size: 14.5px !important; }
.ap-alt a { color: var(--gold-light); }
/* phone: bottom sheet with a big button */
.app-prompt.is-sheet {
  width: 100%; max-width: 520px; margin: auto auto 0; border-radius: 22px 22px 0 0;
  padding: 26px 22px calc(18px + env(safe-area-inset-bottom)); text-align: center;
  animation: ap-up .3s ease-out;
}
.app-prompt.is-sheet .ap-icon { width: 64px; height: 64px; border-radius: 15px; margin: 0 auto 14px; }
.app-prompt.is-sheet h2 { font-size: 28px; }
.app-prompt.is-sheet .ap-points { text-align: left; max-width: 360px; margin-left: auto; margin-right: auto; }
.ap-get { display: flex; width: 100%; margin-top: 20px; padding: 15px; font-size: 19px; }
.is-sheet .ap-later { display: block; margin: 14px auto 0; }
@keyframes ap-up { from { transform: translateY(40px); opacity: 0; } to { transform: none; opacity: 1; } }

/* ---------- Footer ---------- */
footer { background: var(--ink); color: var(--on-dark-muted); font-size: 14.5px; }
footer .wrap { padding-top: 48px; padding-bottom: 40px; }
.foot-cols { display: grid; grid-template-columns: 1.3fr 1fr 1fr 1fr; gap: 28px; padding-bottom: 30px; border-bottom: 1px solid rgba(243, 238, 226, .08); }
.foot-cols h2 { font-family: var(--display); font-size: 16px; letter-spacing: .12em; text-transform: uppercase; color: var(--on-dark); margin-bottom: 12px; }
.foot-cols ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 7px; }
.foot-cols a { text-decoration: none; }
.foot-cols a:hover { color: var(--on-dark); }
.foot-cols p { margin-top: 12px; max-width: 280px; }
.disclaimer { margin-top: 24px; font-size: 13px; line-height: 1.6; color: #8d8f80; max-width: 900px; }
.copy-line { margin-top: 12px; font-size: 13px; color: #6f7163; }

/* ---------- Responsive ---------- */
@media (max-width: 1000px) {
  .layout { grid-template-columns: minmax(0, 1fr); }
  .sidebar { position: static; }
  .test-cards { grid-template-columns: 1fr; }
  .foot-cols { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 860px) {
  .menu-btn { display: block; }
  .nav-links {
    position: absolute; top: 64px; left: 0; right: 0; display: none; flex-direction: column; align-items: stretch; gap: 0;
    padding: 8px 16px 16px; background: var(--olive-950); border-bottom: 1px solid rgba(243, 238, 226, .1);
  }
  .nav-links.open { display: flex; }
  .nav-links a:not(.btn) { padding: 12px 4px; font-size: 17px; border-bottom: 1px solid rgba(243, 238, 226, .08); }
  .nav-links a[aria-current="page"] { box-shadow: none; color: var(--gold); }
  .nav-links .btn { margin-top: 12px; padding: 12px; }
}
@media (max-width: 600px) {
  body { font-size: 16px; }
  .wrap { padding: 0 16px; }
  .brand b { font-size: 18px; }
  .page-hero .wrap { padding-top: 22px; padding-bottom: 36px; }
  .q, .lesson { padding: 18px 16px; }
  .choices.two { grid-template-columns: 1fr; }
  .app-cta { flex-direction: column; align-items: flex-start; }
  .quiz-bar .progress { display: none; }
  .results-head { grid-template-columns: 1fr; justify-items: center; text-align: center; }
  .bar { grid-template-columns: 1fr 60px; }
  .bar .track { grid-column: 1 / -1; grid-row: 2; }
  .pager a { min-width: 0; flex: 1; }
  .foot-cols { grid-template-columns: 1fr; }
  .exam-controls .btn { margin-left: 0; width: 100%; }
  .app-prompt.is-qr { grid-template-columns: 1fr; padding: 24px; }
  .ap-qr { max-width: 220px; margin: 0 auto; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; }
}