@import url("https://fonts.googleapis.com/css2?family=Instrument+Serif:ital@0;1&family=Noto+Sans+TC:wght@400;500;700&family=Noto+Serif+TC:wght@500;600&family=Outfit:wght@400;500;600&display=swap");

:root {
  --bg: #f3eee6;
  --card: #f7f3ec;
  --text: #1c1915;
  --muted: #5e584f;
  --accent: #c2410c;
  --border: rgba(28, 25, 21, 0.16);
  --ok: #2f6b4f;
  --signal: #c2410c;
  --paper: #f3eee6;
  --paper-2: #e7e0d4;
  --ink: #1c1915;
  --serif: "Instrument Serif", "Noto Serif TC", "Songti TC", serif;
  --sans: "Outfit", "Noto Sans TC", "PingFang TC", "Helvetica Neue", sans-serif;
}

html { color-scheme: light; scroll-behavior: smooth; }
body {
  font-family: var(--sans);
  font-weight: 400;
  color: var(--text);
  background: var(--paper);
  line-height: 1.55;
  letter-spacing: -0.011em;
}
::selection { background: var(--ink); color: var(--paper); }
:focus-visible { outline: 2px solid var(--signal); outline-offset: 3px; }

h1, h2, h3, .proof-score, .product-hero h1, .home-hero h2, .product-card h3 {
  font-family: var(--serif);
  font-weight: 400;
  font-synthesis: none;
  letter-spacing: -0.03em;
}
a { color: var(--ink); text-underline-offset: 0.18em; }
.muted { color: var(--muted); }

.site-head,
.page-bands .site-head {
  width: 100%;
  max-width: 100%;
  margin-left: 0;
  background: rgba(243, 238, 230, 0.88);
  border-top: 7px solid var(--ink);
  border-bottom: 1px solid var(--border);
  box-shadow: none;
  backdrop-filter: blur(16px) saturate(140%);
  -webkit-backdrop-filter: blur(16px) saturate(140%);
}
.brand h1, .brand-name {
  font-family: var(--sans);
  font-weight: 600;
  font-size: 0.92rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  line-height: 1.2;
}
.brand .muted { font-size: 0.78rem; letter-spacing: 0; text-transform: none; max-width: 42ch; }
.brand img { width: 40px; height: 40px; border-radius: 2px; }

nav.tabs,
.page-bands nav.tabs {
  background: transparent;
  border-radius: 0;
  padding: 14px 0 2px;
  margin: 8px 0 0;
  gap: 4px 22px;
  font-size: 0.92rem;
  border-top: 0;
}
nav.tabs a,
nav.tabs.sub a {
  color: var(--muted) !important;
  font-weight: 500;
  padding: 4px 0;
  border-radius: 0;
  background: transparent !important;
  text-decoration: none;
  letter-spacing: 0.01em;
}
nav.tabs a:hover, nav.tabs a.active,
nav.tabs.sub a:hover, nav.tabs.sub a.active {
  color: var(--ink) !important;
  background: transparent !important;
  box-shadow: inset 0 -1px 0 var(--signal);
}
nav.tabs.sub {
  background: transparent;
  margin-top: 0;
  padding-top: 2px;
  font-size: 0.78rem;
  letter-spacing: 0.04em;
}
nav.tabs #userBox, nav.tabs #userEmail, nav.tabs #userBox a { color: var(--muted) !important; }
.lang-select, nav.tabs .lang-select {
  border-radius: 0;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--ink);
}

.nav-tree-toggle {
  border-radius: 0;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
}
.nav-tree-panel {
  border-radius: 0;
  border: 1px solid var(--ink);
  background: var(--paper);
  box-shadow: 8px 8px 0 var(--ink);
}
.nav-tree-panel summary { color: var(--signal); }
.nav-tree-panel a { color: var(--ink) !important; }
.nav-tree-panel a.active, .nav-tree-panel a:hover { background: var(--paper-2); }

.page-bands { background: var(--paper); }
.page-bands .band--ink,
.page-bands .home-hero,
.page-bands .product-hero { background: var(--paper); }
.page-bands .band--slate,
.page-bands .home-preview-strip,
.page-bands .explain-map-band,
.page-bands .lesson-try-block,
.page-bands .article.product-story { background: var(--paper-2); }
.page-bands .band--dusk,
.page-bands .system-section,
.page-bands .choose-section { background: #efe8dc; }
.page-bands .band--graphite,
.page-bands .whyus { background: var(--paper); }
.page-bands .band--forest,
.page-bands .final-cta,
.page-bands .diag-cta-banner {
  background: var(--ink);
  color: var(--paper);
}
.page-bands .card,
.page-bands .free-banner {
  background: transparent;
  color: inherit;
}
.page-bands .band { padding: 104px 0; }
.page-bands .diag-cta-banner { padding: 72px 0; }
.page-bands .final-cta { padding: 96px 0; }

.page-bands .wrap.wide { display: flex; flex-direction: column; }
.page-bands .site-head { order: -2; }
.page-bands .product-hero { order: -1; }
.product-card .btn { display: flex; width: 100%; justify-content: center; text-align: center; margin-top: 16px; }
.product-card .text-link { margin-top: 14px; }
.diag-intro h1 {
  font-size: clamp(2.3rem, 5vw, 4rem);
  line-height: 1.08;
  max-width: 16em;
  margin: 0 0 12px;
}

.home-hero, .product-hero {
  border: 0;
  border-radius: 0;
  background: transparent;
  box-shadow: none;
}
.home-hero h2, .product-hero h1, .choose-section h2, .system-section h2, .whyus h2, .final-cta h2, .diag-cta-banner h2, .explain-map-band h2 {
  font-size: clamp(2.6rem, 5.6vw, 5.15rem);
  line-height: 0.96;
  max-width: 16ch;
  margin: 0;
  text-wrap: balance;
}
.hero-lead { text-wrap: pretty; }
.whyus h2, .explain-map-band h2, .system-section h2, .choose-section h2 { max-width: 18ch; }
.hero-lead, .domain-page .domain-lead {
  font-size: 1.12rem;
  line-height: 1.5;
  color: var(--muted);
  max-width: 38rem;
}
.hero-kicker, .section-kicker, .free-banner-kicker, .quiz-result-kicker {
  font-family: var(--sans);
  color: var(--signal);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}
.final-cta .hero-kicker, .diag-cta-banner .hero-kicker,
.final-cta h2, .diag-cta-banner h2, .final-cta p, .diag-cta-banner p { color: var(--paper); }
.diag-cta-banner .hero-kicker, .final-cta .hero-kicker { color: #f0b429; }
.final-cta p, .diag-cta-banner p { color: rgba(243, 238, 230, 0.78); }
.diag-cta-banner h2, .final-cta h2 { max-width: 16ch; }
.page-bands .diag-cta-banner .band-head,
.page-bands .final-cta .band-head { align-items: flex-start; text-align: left; }
.page-bands .diag-cta-banner, .page-bands .final-cta { text-align: left; }
.page-bands .diag-cta-banner .btn-row, .page-bands .final-cta .btn-row { justify-content: flex-start; }
.hero-note { color: var(--muted); }

.proof-card {
  border: 0;
  border-left: 1px solid var(--border);
  border-radius: 0;
  background: transparent;
  padding: 4px 0 4px 28px;
}
.proof-score, .proof-score-sm {
  font-family: var(--serif);
  font-weight: 400;
  font-style: italic;
  font-synthesis: none;
  color: var(--signal);
  letter-spacing: -0.045em;
  line-height: 0.85;
}
.proof-score { font-size: clamp(4.8rem, 8vw, 7.2rem) !important; }
.proof-score-sm { font-size: clamp(3.2rem, 5vw, 4.6rem) !important; }
.proof-score span { font-style: normal; font-family: var(--sans); color: var(--muted); font-size: 1rem; letter-spacing: 0; }
.proof-divider { border-top-color: var(--border); }

.btn {
  border-radius: 0;
  background: var(--ink);
  color: var(--paper) !important;
  padding: 14px 22px;
  font-family: var(--sans);
  font-size: 0.84rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  text-decoration: none;
  transition: background 0.25s ease, transform 0.25s ease, color 0.25s ease;
}
.btn:hover { background: var(--signal); transform: translateY(-2px); }
.btn.ok { background: var(--signal); color: #fff !important; }
.btn.ok:hover { background: #9a3412; }
.btn.secondary {
  background: transparent;
  color: var(--ink) !important;
  border: 1px solid var(--ink);
}
.final-cta .btn.secondary, .diag-cta-banner .btn.secondary {
  color: var(--paper) !important;
  border-color: rgba(243, 238, 230, 0.45);
}
.btn.secondary:hover { background: var(--ink); color: var(--paper) !important; }
.btn.danger { background: #9f1239; }
.btn.small { padding: 8px 12px; letter-spacing: 0.04em; }
.final-cta .btn.ok, .diag-cta-banner .btn.ok { background: var(--paper); color: var(--ink) !important; }
.final-cta .btn.ok:hover, .diag-cta-banner .btn.ok:hover { background: #f0b429; color: var(--ink) !important; }

.text-link, .proof-card a, .footer-links a, footer a {
  text-decoration: none;
  background-image: linear-gradient(currentColor, currentColor);
  background-repeat: no-repeat;
  background-position: 0 100%;
  background-size: 0 1px;
  transition: background-size 0.35s ease;
}
.text-link:hover, .proof-card a:hover, .footer-links a:hover, footer a:hover { background-size: 100% 1px; }

.product-grid { gap: 18px; }
.product-card, .page-bands .product-card {
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 0;
  padding: 28px 26px 26px;
  transition: background 0.3s ease, transform 0.35s ease;
}
.product-card::before { height: 3px; }
.product-card.ai901-product::before, .product-card::before { background: #c2410c; }
.product-card.aifc-product::before { background: #b45309; }
.product-card.ai103-product::before { background: #1e3a5f; }
.product-card:hover { background: rgba(255, 255, 255, 0.45); transform: translateY(-4px); }
.product-label {
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--muted);
}
.product-card h3 { font-size: clamp(3rem, 4vw, 4.4rem); line-height: 0.9; margin: 10px 0 14px; }
.availability, .availability.live { color: var(--signal); font-weight: 500; }
.product-card .text-link { margin-left: 0; margin-right: 16px; }

.system-grid { gap: 0; border-top: 1px solid var(--border); }
.system-grid article, .page-bands .system-grid article {
  background: transparent;
  border: 0;
  border-right: 1px solid var(--border);
  border-radius: 0;
  padding: 28px 22px 8px 0;
}
.system-grid article:last-child { border-right: 0; padding-right: 0; }
.system-grid span {
  font-family: var(--serif);
  font-weight: 400;
  font-style: italic;
  font-size: 2.4rem;
  color: var(--signal);
  letter-spacing: -0.03em;
}
.system-grid strong { font-family: var(--serif); font-weight: 400; font-size: 1.55rem; margin-top: 8px; }
.system-grid p { font-size: 0.92rem; }

.block-icon, .page-bands .block-icon { color: var(--signal); }
.final-cta .block-icon, .diag-cta-banner .block-icon { color: #f0b429; }

.compare-table th, .compare-table td, .article th, .article td, .diag-score-table th, .diag-score-table td {
  border-color: var(--border);
}
.compare-table th:last-child, .compare-table td:last-child { background: transparent; }
.compare-table th:last-child { font-family: var(--serif); font-weight: 400; font-size: 1.25rem; }
.compare-table td:last-child { box-shadow: inset 2px 0 0 var(--signal); }

.explain-map img { border-radius: 0; border: 1px solid var(--ink); background: #fff; }
.explain-map-legend { gap: 0; }
.explain-map-legend li {
  border-radius: 0;
  background: transparent;
  border: 0;
  border-top: 1px solid var(--border);
  text-align: left;
  padding: 16px 12px 0 0;
  font-family: var(--serif);
  font-weight: 400;
  font-size: 1.2rem;
}
.explain-map-legend .n { color: var(--signal); font-style: italic; letter-spacing: 0; font-size: 0.85rem; }
.bank-audit-note, .page-bands .explain-map .bank-audit-note {
  border: 0;
  border-left: 2px solid var(--signal);
  border-radius: 0;
  background: transparent;
  color: var(--muted);
  font-weight: 500;
}

.result-card {
  border-radius: 0;
  border: 1px solid var(--ink);
  background: #fff;
  color: #334;
  padding: 12px;
  box-shadow: 14px 14px 0 var(--ink);
}
.result-card img, .fig-right img, .fig-wide img { border-radius: 0; }
.fig-right img { border: 1px solid var(--ink); background: #fff; }

.card, .article, .tips, .topic-card, .lesson-try-block, .lesson-preview, .editorial-box, .free-banner, .home-preview-strip {
  border-radius: 0;
  border-color: var(--border);
  background: transparent;
}
.topic-card { background: rgba(255, 255, 255, 0.35); }
.topic-card:hover { border-color: var(--ink); transform: translateY(-3px); }
.topic-card strong { font-family: var(--serif); font-weight: 400; font-size: 1.45rem; color: var(--ink); }
.editorial-box { background: transparent; border-color: var(--border); }
.home-preview-grid .product-label { color: var(--signal); }

input[type=email], input[type=password], input[type=text], input[type=search],
input[type=number], input[type=datetime-local], select, textarea {
  border-radius: 0;
  border: 1px solid var(--ink);
  background: #fff;
  color: var(--ink);
}
.quiz-choice, .quiz-feedback, .practice-section, .paywall, .diag-rule, .diag-chart-plot, .domain-page .checklist {
  border-radius: 0;
  background: rgba(255, 255, 255, 0.55);
  border-color: var(--border);
  color: var(--text);
}
.practice-section, .paywall { border: 1px solid var(--ink); background: #fff; }
.quiz-choice { background: #fff; }
.quiz-choice:hover { border-color: var(--ink); }
.quiz-choice.correct { border-color: var(--ok); background: #e7f2eb; }
.quiz-choice.wrong { border-color: #9f1239; background: #fde8ec; }
.quiz-feedback { background: var(--paper); }
.quiz-domain, .quiz-score, .study-plan-table td:first-child { color: var(--signal); }
.diag-chart-plot { background: #fff; }
.diag-chart-bar.pos { background: var(--ok); }
.diag-chart-bar.neg, .diag-chart-col.is-weak .diag-chart-bar.neg { background: var(--signal); }
.diag-score-table th { background: var(--paper-2); color: var(--muted); }
.diag-score-table .is-weak td { background: #f8efe4; color: var(--ink); }
.diag-bar { background: var(--paper-2); border-radius: 0; }
.diag-bar-fill { background: var(--signal); }
.paywall-loss { background: #fde8ec; }
.paywall-gain { background: #e7f2eb; }
.badge { border-radius: 0; background: #e7f2eb; color: var(--ok); }
.price-row.ok, .ok { color: var(--ok); }

footer, .footer-links { color: var(--muted); }
.footer-links { display: flex; flex-wrap: wrap; gap: 8px 22px; }
.footer-links a { color: var(--muted); text-decoration: none; }

@media (prefers-reduced-motion: no-preference) {
  .home-hero .hero-copy > *,
  .product-hero .band-inner > div:first-child > * {
    animation: craft-rise 0.9s cubic-bezier(0.16, 1, 0.3, 1) both;
  }
  .home-hero .hero-copy > *:nth-child(2),
  .product-hero .band-inner > div:first-child > *:nth-child(2) { animation-delay: 0.08s; }
  .home-hero .hero-copy > *:nth-child(3),
  .product-hero .band-inner > div:first-child > *:nth-child(3) { animation-delay: 0.16s; }
  .home-hero .hero-copy > *:nth-child(4),
  .product-hero .band-inner > div:first-child > *:nth-child(4) { animation-delay: 0.24s; }
}
@keyframes craft-rise {
  from { opacity: 0; transform: translateY(18px); }
  to { opacity: 1; transform: none; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .product-card, .btn, .topic-card { transition: none; }
}

@media (max-width: 820px) {
  .page-bands .band, .page-bands .diag-cta-banner, .page-bands .final-cta { padding: 64px 0; }
  .home-hero h2, .product-hero h1, .choose-section h2, .system-section h2, .whyus h2, .final-cta h2, .diag-cta-banner h2 {
    font-size: clamp(2.3rem, 11vw, 3.4rem);
    max-width: none;
  }
  .proof-card { border-left: 0; border-top: 1px solid var(--border); padding: 22px 0 0; }
  .system-grid article, .page-bands .system-grid article { border-right: 0; border-bottom: 1px solid var(--border); padding-right: 0; }
  .result-card { box-shadow: 8px 8px 0 var(--ink); }
  .product-card .text-link { margin-right: 0; }
}
@media (max-width: 880px) {
  .site-head, .page-bands .site-head {
    width: 100%;
    max-width: 100%;
    margin-left: 0;
  }
}

/* pass 2 — alignment, contrast, type measure */
.page-bands .site-head .band-inner {
  width: min(1120px, calc(100% - 64px));
  margin-inline: auto;
}
.page-bands .site-head .brand {
  width: auto;
  max-width: none;
  margin: 0;
}
.home-hero { overflow: visible; }
.proof-card, .proof-score { overflow: visible; max-width: 100%; }
.page-bands .brand .muted { display: none; }
.language-support {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}
.lang-select, nav.tabs .lang-select {
  border: 0;
  background: transparent;
  color: var(--ink);
  font-weight: 600;
  letter-spacing: 0.04em;
  padding: 4px 0;
}
.block-icon, .page-bands .block-icon { display: none; }
.page-bands .btn,
.page-bands .btn.ok,
.page-bands .btn.secondary,
.page-bands .btn.danger {
  border-radius: 0;
  text-transform: none;
  letter-spacing: -0.01em;
  font-size: 0.95rem;
  font-weight: 600;
}
.page-bands .home-hero,
.page-bands .product-hero { padding: 36px 0 88px; }
.proof-score span {
  display: block;
  margin-top: 10px;
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.proof-card p { max-width: 28ch; }
.page-bands .product-card,
.page-bands .system-grid article,
.page-bands .topic-card { border-radius: 0; }
html[lang^="zh"] h1,
html[lang^="zh"] h2,
html[lang^="zh"] h3,
html[lang="ja"] h1,
html[lang="ja"] h2,
html[lang="ja"] h3,
html[lang="ko"] h1,
html[lang="ko"] h2,
html[lang="ko"] h3 {
  line-height: 1.22;
  letter-spacing: 0;
}
html[lang^="zh"] .home-hero h2,
html[lang^="zh"] .product-hero h1,
html[lang^="zh"] .choose-section h2,
html[lang^="zh"] .system-section h2,
html[lang^="zh"] .whyus h2,
html[lang^="zh"] .final-cta h2,
html[lang^="zh"] .diag-cta-banner h2,
html[lang="ja"] .home-hero h2,
html[lang="ja"] .product-hero h1,
html[lang="ko"] .home-hero h2,
html[lang="ko"] .product-hero h1 {
  font-size: clamp(2.2rem, 4.4vw, 3.8rem);
  max-width: 14em;
}
a[href*="play.google.com"]::before,
a[href*="apps.apple.com"]::before,
a[href$=".apk"]::before,
[data-i18n="index.dl.apple"]::before,
[data-i18n="index.dl.google"]::before {
  content: "";
  display: inline-block;
  width: 1.15em;
  height: 1.15em;
  margin-right: 0.45em;
  vertical-align: -0.18em;
  background: center / contain no-repeat;
}
a[href*="play.google.com"]::before,
[data-i18n="index.dl.google"]::before {
  background-image: url("/assets/img/google-play.svg");
}
a[href*="apps.apple.com"]::before,
[data-i18n="index.dl.apple"]::before {
  background-color: currentColor;
  -webkit-mask: url("/assets/img/apple.svg") center / contain no-repeat;
  mask: url("/assets/img/apple.svg") center / contain no-repeat;
}
a[href$=".apk"]::before {
  background-image: url("/assets/img/android.svg");
}

/* pass 3 — vivid palette + illustrations (assets/img/illus/*.svg) */
:root {
  --c-orange: #e4572e;
  --c-amber: #e4670f;
  --c-yellow: #f5b301;
  --c-teal: #0f8b8d;
  --c-blue: #2563eb;
  --c-violet: #7c3aed;
  --c-pink: #e0457b;
  --c-green: #2f9e6b;
  --rainbow: linear-gradient(90deg, var(--c-orange), var(--c-yellow), var(--c-green), var(--c-teal), var(--c-blue), var(--c-violet), var(--c-pink));
}
.site-head, .page-bands .site-head {
  border-top: 0;
  background:
    var(--rainbow) top / 100% 7px no-repeat,
    rgba(243, 238, 230, 0.9);
  padding-top: 17px;
}
nav.tabs a:hover, nav.tabs a.active,
nav.tabs.sub a:hover, nav.tabs.sub a.active { box-shadow: inset 0 -2px 0 var(--c-teal); }
nav.tabs a[href*="ai901"]:hover, nav.tabs a[href*="ai901"].active { box-shadow: inset 0 -2px 0 var(--c-blue); }
nav.tabs a[href*="aifc01"]:hover, nav.tabs a[href*="aifc01"].active { box-shadow: inset 0 -2px 0 var(--c-amber); }
nav.tabs a[href*="ai103"]:hover, nav.tabs a[href*="ai103"].active { box-shadow: inset 0 -2px 0 var(--c-violet); }

.page-bands .home-hero,
.page-bands .product-hero {
  background:
    radial-gradient(circle at 90% 6%, rgba(245, 179, 1, 0.3), transparent 30%),
    radial-gradient(circle at 2% 98%, rgba(15, 139, 141, 0.2), transparent 34%),
    radial-gradient(circle at 62% 112%, rgba(224, 69, 123, 0.16), transparent 32%),
    radial-gradient(circle at 38% -8%, rgba(124, 58, 237, 0.1), transparent 28%),
    var(--paper);
}
.page-bands .explain-map-band { background: #e1f1ed; }
.page-bands .home-preview-strip,
.page-bands .lesson-try-block { background: #fff1cf; }
.page-bands .choose-section { background: #e7ebfb; }
.page-bands .system-section { background: #fbe8e1; }
.page-bands .article.product-story { background: #f1eafb; }
.page-bands .final-cta { background: linear-gradient(120deg, #312e81 0%, #1d4ed8 48%, #0f8b8d 100%); }
.page-bands .diag-cta-banner { background: linear-gradient(120deg, #312e81 0%, #6d28d9 52%, #be185d 100%); }
.final-cta p, .diag-cta-banner p { color: rgba(255, 255, 255, 0.86); }

.explain-map-band .section-kicker { color: var(--c-teal); }
.home-preview-strip .section-kicker, .lesson-try-block .section-kicker { color: #a15c00; }
.choose-section .section-kicker { color: var(--c-blue); }
.system-section .section-kicker { color: var(--c-orange); }

/* hero illustration + per-cert score colours */
.proof-card::before {
  content: "";
  display: block;
  width: 100%;
  max-width: 340px;
  aspect-ratio: 2 / 1;
  margin: 0 0 20px;
  background: url("/assets/img/illus/hero-sprint.svg") left center / contain no-repeat;
}
.proof-card { border-left: 3px solid transparent; border-image: linear-gradient(180deg, var(--c-blue), var(--c-violet), var(--c-amber)) 1; }
.proof-score { color: var(--c-blue); }
.proof-score-sm { color: var(--c-amber); }

.page-bands .btn, .page-bands .btn.ok, .page-bands .btn.secondary, .page-bands .btn.danger { border-radius: 10px; }
.btn.ok { background: var(--c-orange); box-shadow: 0 6px 0 rgba(28, 25, 21, 0.14); }
.btn.ok:hover { background: #c2410c; box-shadow: 0 8px 0 rgba(28, 25, 21, 0.14); }
.final-cta .btn.ok, .diag-cta-banner .btn.ok { background: var(--c-yellow); box-shadow: 0 6px 0 rgba(0, 0, 0, 0.25); }
.final-cta .btn.ok:hover, .diag-cta-banner .btn.ok:hover { background: #fff; }

/* cert cards: ai901 blue, aifc01 amber, ai103 violet */
.page-bands .product-card { border-radius: 16px; background: rgba(255, 255, 255, 0.72); border-color: transparent; box-shadow: 0 10px 30px rgba(49, 46, 129, 0.08); }
.product-card:hover { background: #fff; }
.product-card::before { height: 6px; }
.product-card.ai901-product { --cert: var(--c-blue); }
.product-card.aifc-product { --cert: var(--c-amber); }
.product-card.ai103-product { --cert: var(--c-violet); }
.product-card.ai901-product::before, .product-card.aifc-product::before, .product-card.ai103-product::before { background: var(--cert); }
.product-card[class*="-product"] h3, .product-card[class*="-product"] .availability { color: var(--cert); }
.product-card[class*="-product"] .btn.ok { background: var(--cert); }
.product-card[class*="-product"] .btn.ok:hover { filter: brightness(0.88); }
.product-card .product-label { padding-right: 76px; }
.product-card[class*="-product"]::after {
  content: "";
  position: absolute;
  top: 18px;
  right: 16px;
  width: 72px;
  height: 72px;
  background: center / contain no-repeat;
}
.product-card.ai901-product::after { background-image: url("/assets/img/illus/cert-ai901.svg"); }
.product-card.aifc-product::after { background-image: url("/assets/img/illus/cert-aifc01.svg"); }
.product-card.ai103-product::after { background-image: url("/assets/img/illus/cert-ai103.svg"); }
.home-preview-grid > div:nth-child(1) .product-label { color: var(--c-blue); }
.home-preview-grid > div:nth-child(2) .product-label { color: var(--c-amber); }
.home-preview-grid > div:nth-child(3) .product-label { color: var(--c-violet); }

/* 4-step icons */
.system-grid article::before,
.page-bands .feat-list li::before {
  content: "";
  display: block;
  flex: 0 0 auto;
  width: 64px;
  height: 64px;
  margin-bottom: 14px;
  background: center / contain no-repeat;
}
.page-bands .feat-list li::before { width: 48px; height: 48px; margin: 0; }
.system-grid article:nth-child(4n+1)::before, .page-bands .feat-list li:nth-child(4n+1)::before { background-image: url("/assets/img/illus/step-diagnose.svg"); }
.system-grid article:nth-child(4n+2)::before, .page-bands .feat-list li:nth-child(4n+2)::before { background-image: url("/assets/img/illus/step-report.svg"); }
.system-grid article:nth-child(4n+3)::before, .page-bands .feat-list li:nth-child(4n+3)::before { background-image: url("/assets/img/illus/step-repair.svg"); }
.system-grid article:nth-child(4n+4)::before, .page-bands .feat-list li:nth-child(4n+4)::before { background-image: url("/assets/img/illus/step-confirm.svg"); }
.system-grid article:nth-child(4n+1) span { color: var(--c-orange); }
.system-grid article:nth-child(4n+2) span { color: var(--c-teal); }
.system-grid article:nth-child(4n+3) span { color: var(--c-blue); }
.system-grid article:nth-child(4n+4) span { color: var(--c-violet); }
.system-grid article, .page-bands .system-grid article { padding-left: 22px; }
.system-grid article:first-child { padding-left: 0; }

.explain-map img { border-radius: 14px; box-shadow: 10px 10px 0 var(--c-teal); }
.explain-map-legend { margin-top: 28px; }
.explain-map-legend li { border-top: 4px solid var(--c-orange); }
.explain-map-legend li:nth-child(2) { border-top-color: var(--c-green); }
.explain-map-legend li:nth-child(3) { border-top-color: var(--c-blue); }
.explain-map-legend li:nth-child(4) { border-top-color: var(--c-violet); }
.explain-map-legend li:nth-child(1) .n { color: var(--c-orange); }
.explain-map-legend li:nth-child(2) .n { color: var(--c-green); }
.explain-map-legend li:nth-child(3) .n { color: var(--c-blue); }
.explain-map-legend li:nth-child(4) .n { color: var(--c-violet); }
.bank-audit-note, .page-bands .explain-map .bank-audit-note { border-left-color: var(--c-teal); }

.compare-table th:first-child { color: var(--muted); }
.compare-table th:last-child { color: var(--c-green); }
.compare-table th:last-child, .compare-table td:last-child { background: rgba(47, 158, 107, 0.1); }
.compare-table td:last-child { box-shadow: inset 3px 0 0 var(--c-green); }
.topic-card { border-top: 4px solid var(--c-teal); }
.topic-card:nth-child(4n+2) { border-top-color: var(--c-blue); }
.topic-card:nth-child(4n+3) { border-top-color: var(--c-violet); }
.topic-card:nth-child(4n+4) { border-top-color: var(--c-amber); }

/* band illustrations (desktop only) */
@media (min-width: 900px) {
  .home-preview-strip .band-inner,
  .lesson-try-block .band-inner,
  .final-cta .band-inner,
  .diag-cta-banner .band-inner { position: relative; }
  .home-preview-strip .band-inner::after,
  .lesson-try-block .band-inner::after {
    content: "";
    position: absolute;
    top: 0;
    right: 0;
    width: 220px;
    height: 80px;
    background: url("/assets/img/illus/audio-wave.svg") center / contain no-repeat;
    pointer-events: none;
  }
  .final-cta .band-inner::after,
  .diag-cta-banner .band-inner::after {
    content: "";
    position: absolute;
    top: 50%;
    right: 0;
    width: 200px;
    height: 200px;
    transform: translateY(-50%);
    background: url("/assets/img/illus/cta-rocket.svg") center / contain no-repeat;
    pointer-events: none;
  }
  .final-cta .band-inner > *, .diag-cta-banner .band-inner > * { max-width: calc(100% - 230px); }
}
@media (max-width: 820px) {
  .proof-card { border-image: none; border-left: 0; }
  .system-grid article, .page-bands .system-grid article { padding-left: 0; }
}
.product-hero .lesson-preview,
.lesson-preview-hero.lesson-preview,
.lesson-preview {
  border: 0;
  border-top: 4px solid var(--c-teal);
  border-radius: 12px;
  background: #fff;
  box-shadow: 0 8px 24px rgba(161, 92, 0, 0.1);
}
.home-preview-grid > div:nth-child(1) .lesson-preview { border-top-color: var(--c-blue); }
.home-preview-grid > div:nth-child(2) .lesson-preview { border-top-color: var(--c-amber); }
.home-preview-grid > div:nth-child(3) .lesson-preview { border-top-color: var(--c-violet); }
.lesson-preview-h { color: var(--ink); }
.lesson-preview-kicker { color: var(--c-teal); }
.feat-list strong { color: var(--ink); }