@font-face {
  font-family: "Duoyingde Sans";
  src: url("assets/brand-display.woff2?v=20260922-paid") format("woff2");
  font-style: normal;
  font-weight: 100 900;
  font-display: swap;
}

:root {
  --ink: #10173c;
  --muted: #5f6680;
  --blue: #4259e9;
  --blue-deep: #252eaa;
  --purple: #785cf4;
  --mist: #f6f4ff;
  --lilac: #e9e4ff;
  --line: #dfe1ec;
  --paper: #ffffff;
  --round: 1rem;
  --display: "Duoyingde Sans", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 6.5rem; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: var(--body); font-size: 16px; line-height: 1.6; }
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; }

:focus-visible { outline: 3px solid #252eaa; outline-offset: 4px; }
.closing :focus-visible, .questions :focus-visible { outline-color: #ffffff; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.skip-link { position: fixed; z-index: 20; left: 1rem; top: -4rem; padding: .65rem 1rem; border-radius: .5rem; background: var(--ink); color: #fff; font-weight: 700; transition: top .2s ease; }
.skip-link:focus { top: 1rem; }

.site-header { position: relative; z-index: 10; padding: 1.25rem clamp(1.25rem, 4.2vw, 4.5rem) 0; }
.nav-wrap { max-width: 1320px; min-height: 3.5rem; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; gap: 1.5rem; }
.brand, .footer-brand { display: inline-flex; align-items: center; gap: .7rem; font-family: var(--display); font-size: 1.2rem; font-weight: 760; letter-spacing: -.04em; }
.brand img { width: 2.75rem; height: 2.75rem; border-radius: .75rem; box-shadow: 0 5px 14px rgba(70, 53, 183, .16); }
.site-nav { display: flex; align-items: center; gap: clamp(1rem, 2.1vw, 2rem); color: #363d60; font-size: .9rem; font-weight: 650; }
.site-nav > a:not(.nav-status) { padding: .6rem 0; }
.site-nav > a:not(.nav-status):hover { color: var(--blue); }
.nav-status { display: inline-flex; align-items: center; gap: .5rem; padding: .56rem .82rem; border: 1px solid #d8d6fa; border-radius: 99px; color: #45429a; background: #fbfaff; font-size: .78rem; }
.nav-status i { width: .42rem; height: .42rem; border-radius: 50%; background: #7d68f8; box-shadow: 0 0 0 4px #efedff; }
.menu-toggle { display: none; width: 44px; height: 44px; border: 1px solid var(--line); border-radius: .7rem; background: #fff; cursor: pointer; }
.menu-toggle span:not(.sr-only) { display: block; width: 18px; height: 2px; margin: 4px auto; border-radius: 2px; background: var(--ink); transition: transform .2s ease; }

.hero { max-width: 1320px; min-height: 760px; margin: 0 auto; padding: 4.25rem clamp(1.25rem, 4.2vw, 4rem) 5rem; display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr); align-items: center; gap: 2.5rem; }
.hero-copy { position: relative; z-index: 2; max-width: 660px; }
h1, h2, h3, p { margin-top: 0; }
h1, h2, h3 { font-family: var(--display); letter-spacing: -.03em; line-height: 1.22; }
h1 { max-width: 680px; margin-bottom: 1.7rem; font-size: clamp(2.75rem, 4.85vw, 4.4rem); font-weight: 820; }
.hero-intro { max-width: 440px; margin-bottom: 2.15rem; color: var(--muted); font-size: 1.03rem; line-height: 1.8; }
.hero-actions { display: flex; align-items: center; gap: 1.15rem; }
.hero-actions p { margin: 0; color: var(--muted); font-size: .84rem; font-weight: 650; }
.button { display: inline-flex; min-height: 50px; align-items: center; justify-content: center; gap: .8rem; padding: .75rem 1.15rem; border-radius: .7rem; font-weight: 800; transition: transform .2s ease, box-shadow .2s ease, background .2s ease; }
.button:hover { transform: translateY(-2px); }
.button-primary { color: #fff; background: var(--blue); box-shadow: 0 10px 22px rgba(66, 89, 233, .24); }
.button-primary:hover { background: var(--blue-deep); box-shadow: 0 13px 28px rgba(66, 89, 233, .3); }
.hero-footnote { margin-top: 3.25rem; display: flex; align-items: center; gap: 1rem; color: #505878; font-size: .82rem; font-weight: 700; }
.hero-footnote span + span { display: inline-flex; align-items: center; gap: 1rem; }
.hero-footnote span + span::before { width: 2.4rem; height: 1px; background: #b3b8cb; content: ""; }

.hero-visual { position: relative; width: min(100%, 500px); min-height: 0; padding: 1rem 0 2.5rem; justify-self: center; display: flex; align-items: center; justify-content: center; }
.hero-visual::before { position: absolute; width: 92%; height: 91%; border-radius: 1rem; background: var(--lilac); content: ""; }
.phone { position: relative; overflow: hidden; border: 6px solid #1a1b31; border-radius: 2.15rem; background: #16182f; box-shadow: 0 28px 55px rgba(31, 28, 85, .25), 0 4px 12px rgba(31, 28, 85, .2); }
.phone img { width: 100%; height: auto; object-fit: contain; }
.hero-phone { width: min(72%, 278px); border-width: 5px; border-radius: 2rem; }
.screenshot-caption { margin: 0; color: #61677e; font-size: .72rem; font-weight: 650; letter-spacing: .04em; }
.hero-visual > .screenshot-caption { position: absolute; bottom: 0; left: 50%; transform: translateX(-50%); }

.training-path { padding: clamp(4.5rem, 8vw, 7rem) clamp(1.25rem, 4.2vw, 4.5rem); background: var(--mist); }
.section-intro { max-width: 1320px; margin: 0 auto clamp(2.5rem, 5vw, 4rem); }
h2 { margin-bottom: 0; font-size: clamp(2.15rem, 4vw, 3.5rem); font-weight: 800; }
.training-stage { max-width: 1120px; margin: 0 auto; display: grid; grid-template-columns: minmax(0, 1fr) 310px; align-items: center; gap: clamp(2.5rem, 9vw, 9rem); }
.stage-panel { padding-left: clamp(0rem, 4vw, 3.5rem); }
.stage-number { margin-bottom: 1.4rem; color: var(--purple); font-family: var(--display); font-size: .85rem; font-weight: 850; letter-spacing: .1em; }
.stage-copy { min-height: 190px; }
.stage-copy h3 { max-width: 430px; margin-bottom: 1.1rem; font-size: clamp(2rem, 3.35vw, 3.2rem); font-weight: 780; }
.stage-copy p { max-width: 410px; color: var(--muted); line-height: 1.8; }
.step-tabs { display: flex; flex-wrap: wrap; gap: .55rem; margin-top: 2.2rem; }
.step-tab { min-height: 44px; padding: .55rem .88rem; border: 1px solid #cfd1df; border-radius: 99px; color: #4a5170; background: transparent; font-size: .87rem; font-weight: 760; cursor: pointer; transition: color .2s ease, background .2s ease, border-color .2s ease; }
.step-tab:hover, .step-tab.is-active { border-color: var(--ink); color: #fff; background: var(--ink); }
.stage-note { margin: .85rem 0 0; color: #626982; font-size: .75rem; }
.stage-image-wrap { text-align: center; }
.stage-phone { width: 260px; margin: 0 auto .85rem; transition: opacity .16s ease, transform .16s ease; }
.stage-phone.is-switching { opacity: .36; transform: translateY(5px); }

.range-section { max-width: 1320px; margin: 0 auto; padding: clamp(5rem, 9vw, 8rem) clamp(1.25rem, 4.2vw, 4.5rem); display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr); align-items: center; gap: clamp(2.5rem, 6vw, 5rem); }
.range-image { position: relative; min-height: 590px; display: flex; align-items: center; justify-content: center; }
.range-surface { position: absolute; width: 96%; height: 91%; border-radius: 1rem; background: #eaf0ff; }
.combo-phone { width: min(73%, 280px); border-color: #18233e; }
.range-image > .screenshot-caption { position: absolute; bottom: 0; left: 50%; transform: translateX(-50%); }
.range-copy { max-width: 500px; }
.check-list { display: grid; gap: 1rem; margin: 2.25rem 0 0; padding: 0; list-style: none; }
.check-list li { display: flex; align-items: center; gap: .85rem; font-size: .92rem; font-weight: 720; }
.check-list span { color: var(--purple); font-family: var(--display); font-size: .76rem; font-weight: 850; }

.questions { padding: clamp(4.5rem, 8vw, 7rem) clamp(1.25rem, 4.2vw, 4.5rem); color: #fff; background: var(--ink); }
.questions > * { max-width: 1320px; margin-left: auto; margin-right: auto; }
.questions-heading { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; align-items: end; }
.questions-heading h2 { grid-column: 1 / 2; }
.question-list { margin-top: clamp(3.5rem, 7vw, 6.5rem); border-top: 1px solid rgba(223,225,236,.28); }
.question-list article { display: grid; grid-template-columns: 6rem minmax(180px, .65fr) 1fr; gap: 1.5rem; align-items: baseline; padding: 2rem 0; border-bottom: 1px solid rgba(223,225,236,.28); }
.question-index { margin: 0; color: #8b9cff; font-family: var(--display); font-size: .85rem; font-weight: 850; }
.question-list h3 { margin: 0; font-size: clamp(1.35rem, 2vw, 1.75rem); font-weight: 730; }
.question-list article > p:last-child { max-width: 440px; margin: 0; color: #c4c8df; font-size: .94rem; }

.launch-section { max-width: 1320px; margin: 0 auto; padding: clamp(4.5rem, 8vw, 7rem) clamp(1.25rem, 4.2vw, 4.5rem); display: grid; grid-template-columns: minmax(0, 1fr) minmax(280px, .5fr); gap: clamp(3rem, 10vw, 10rem); align-items: center; }
.launch-copy { max-width: 700px; }
.launch-copy .launch-current { padding: 1rem 0; border-top: 1px solid var(--line); color: #424966; font-size: .91rem; }
.launch-current strong { color: var(--ink); }
.launch-card { min-height: 290px; padding: 2.2rem; border-radius: var(--round); background: #f1efff; box-shadow: inset 0 0 0 1px #e5e1ff; }
.launch-card img { width: 76px; border-radius: 1.25rem; box-shadow: 0 10px 18px rgba(64, 53, 179, .14); }
.launch-card p { margin: 1.65rem 0 .25rem; font-family: var(--display); font-size: 1.32rem; font-weight: 800; letter-spacing: -.04em; }
.launch-card strong { display: block; color: #404899; font-size: .91rem; }
.launch-card span { display: block; margin-top: 2rem; color: #5f6680; font-size: .78rem; }

.faq-section { padding: clamp(4.5rem, 8vw, 7rem) clamp(1.25rem, 4.2vw, 4.5rem); background: #f8f8fb; display: grid; grid-template-columns: minmax(0, .72fr) minmax(0, 1fr); gap: clamp(3rem, 10vw, 10rem); }
.faq-intro, .faq-list { max-width: 540px; }
.faq-list { width: 100%; }
details { border-top: 1px solid #d6d8e2; }
details:last-child { border-bottom: 1px solid #d6d8e2; }
summary { display: flex; min-height: 64px; align-items: center; justify-content: space-between; gap: 1rem; list-style: none; color: #252c4c; font-weight: 760; cursor: pointer; }
summary::-webkit-details-marker { display: none; }
summary span { color: var(--blue); font-size: 1.45rem; font-weight: 400; transition: transform .2s ease; }
details[open] summary span { transform: rotate(45deg); }
details p { max-width: 470px; margin: -.25rem 2.5rem 1.3rem 0; color: var(--muted); font-size: .92rem; }

.closing { min-height: 410px; padding: 6rem 1.25rem; display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center; color: #fff; background: var(--blue-deep); }
.closing h2 { margin-bottom: 2.3rem; }
.button-light { color: #2e37b6; background: #fff; box-shadow: 0 8px 24px rgba(24, 23, 105, .17); }

.site-footer { max-width: 1320px; margin: 0 auto; padding: 2.2rem clamp(1.25rem, 4.2vw, 4.5rem) 2.8rem; display: grid; grid-template-columns: 1fr 1fr auto; gap: 1rem; align-items: center; color: #565d78; font-size: .76rem; }
.footer-brand { color: var(--ink); font-size: 1rem; }
.footer-brand img { width: 32px; height: 32px; border-radius: .55rem; }
.site-footer > p { margin: 0; }
.legal-links { display: flex; gap: 1.3rem; text-align: right; }
.legal-links a { text-decoration: underline; text-decoration-color: #bcc0d0; text-underline-offset: 3px; }
.legal-links a:hover { color: var(--blue); }

@media (max-width: 820px) {
  .site-header { padding-top: .8rem; }
  .nav-wrap { min-height: 3.2rem; }
  .menu-toggle { display: block; }
  .site-nav { position: absolute; top: calc(100% + .75rem); left: 1.25rem; right: 1.25rem; display: none; padding: .65rem; border: 1px solid #e1e2ed; border-radius: 1rem; background: rgba(255,255,255,.98); box-shadow: 0 18px 35px rgba(23, 28, 70, .12); }
  .site-nav.is-open { display: grid; }
  .site-nav a { min-height: 44px; display: flex; align-items: center; padding: .45rem .65rem; border-radius: .5rem; }
  .site-nav a:hover { background: #f4f3fe; }
  .nav-status { justify-content: flex-start; }
  .hero { grid-template-columns: 1fr; padding-top: 4.4rem; text-align: center; }
  .hero-copy { margin: 0 auto; }
  .hero-intro { margin-left: auto; margin-right: auto; }
  .hero-actions, .hero-footnote { justify-content: center; }
  .hero-visual { min-height: 0; margin-top: .5rem; }
  .training-stage { grid-template-columns: 1fr; gap: 2.5rem; }
  .stage-panel { padding: 0; }
  .range-section { grid-template-columns: 1fr; }
  .range-image { order: 2; min-height: 530px; }
  .range-copy { max-width: 610px; }
  .questions-heading { display: block; }
  .questions-heading h2 { margin-top: 2rem; }
  .question-list article { grid-template-columns: 3.5rem 1fr; gap: 1rem; }
  .question-list article > p:last-child { grid-column: 2; }
  .launch-section { grid-template-columns: 1fr; }
  .launch-card { max-width: 430px; }
  .faq-section { grid-template-columns: 1fr; }
  .site-footer { grid-template-columns: 1fr 1fr; }
  .legal-links { grid-column: 1 / -1; text-align: left; }
}

@media (max-width: 480px) {
  .site-header { padding-left: 1rem; padding-right: 1rem; }
  .site-nav { left: 1rem; right: 1rem; }
  .hero { min-height: auto; padding: 3.4rem 1.25rem 4.5rem; }
  h1 { font-size: clamp(2.3rem, 10.4vw, 3.2rem); }
  .hero-intro { font-size: .95rem; }
  .hero-actions { flex-direction: column; gap: .85rem; }
  .hero-footnote { gap: 1rem; margin-top: 2rem; }
  .hero-footnote span + span::before { width: 1rem; }
  .hero-visual { min-height: 0; }
  .hero-phone { width: 250px; }
  .training-path, .range-section, .questions, .launch-section, .faq-section { padding-left: 1.25rem; padding-right: 1.25rem; }
  .stage-copy { min-height: 165px; }
  .stage-phone { width: 235px; }
  .range-image { min-height: 475px; }
  .combo-phone { width: 250px; }
  .question-list article { grid-template-columns: 1fr; gap: .55rem; }
  .question-list article > p:last-child { grid-column: auto; }
  .launch-card { min-height: 250px; }
  .site-footer { padding-left: 1.25rem; padding-right: 1.25rem; grid-template-columns: 1fr; }
  .legal-links { flex-direction: column; gap: .6rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; }
}

/* Surface details, kept within the standalone marketing page. */
::selection { background: #dcd8ff; color: #10173c; }
html { scrollbar-color: #b7bae0 #f6f4ff; }
body { caret-color: var(--blue); }
.hero-intro { max-width: 30rem; }
.range-copy > p { margin-top: 1.6rem; color: var(--muted); line-height: 1.8; }
.launch-copy > p { max-width: 570px; margin-top: 1.65rem; color: var(--muted); line-height: 1.8; }
.closing-status { color: #dfe0ff; font-size: .85rem; margin-bottom: 1.25rem; }
.stage-number, .check-list span { font-variant-numeric: tabular-nums; }
.legal-links a:focus-visible, summary:focus-visible { border-radius: 3px; }
@media (min-width: 821px) and (max-width: 1100px) { h1 { font-size: 3.1rem; } .site-nav { gap: 1rem; } .nav-status { display: none; } }
@media (max-width: 480px) { .hero { padding-top: 2.8rem; } .hero-visual { margin-top: 1.5rem; } .questions-heading h2 { margin-top: 0; } .stage-copy { min-height: 135px; } .range-image { padding-bottom: 2rem; } }

.closing h2 { margin-bottom: 1.25rem; }
.closing-status { margin-bottom: 2rem; }
summary span { display: inline-flex; align-items: center; }
.button-arrow { flex-shrink: 0; }

/* 2026-09-22: user supplied two-column combo reference.
   Enlarge the detail image instead of shrinking two columns inside a narrow phone. */
.combo-phone { width: min(96%, 390px); border-width: 1px; border-radius: 1.15rem; }
.range-image { min-height: 550px; padding: 2rem 0 3rem; }
.range-image > .screenshot-caption { white-space: nowrap; }
@media (max-width: 480px) {
  .combo-phone { width: 100%; }
  .range-image { min-height: 0; padding: 1.4rem 0 2.8rem; }
  .range-surface { width: calc(100% + 1rem); height: 100%; }
}

/* User-defined paid benefit: extra practice based on individual weaknesses. */
.membership-section { padding: clamp(4.5rem, 8vw, 7rem) clamp(1.25rem, 4.2vw, 4.5rem); background: var(--mist); }
.membership-inner { max-width: 1176px; margin: 0 auto; display: grid; grid-template-columns: 1.1fr 1fr; align-items: center; gap: clamp(2.5rem, 8vw, 7rem); }
.membership-label { margin-bottom: 1.4rem; color: var(--blue-deep); font-size: .85rem; font-weight: 750; }
.membership-label span { margin-left: .7rem; padding-left: .7rem; border-left: 1px solid #c5c3da; color: var(--muted); font-weight: 400; }
.membership-description { max-width: 450px; margin: 1.6rem 0 1.4rem; color: var(--muted); line-height: 1.8; }
.membership-link { min-height: 44px; display: inline-flex; align-items: center; gap: .75rem; color: var(--blue-deep); font-size: .9rem; font-weight: 750; }
.membership-link:hover { text-decoration: underline; text-underline-offset: 4px; }
.membership-steps { margin: 0; padding: 0; list-style: none; }
.membership-steps li { display: grid; grid-template-columns: 2.25rem 1fr; gap: 1rem; padding: 1.7rem 0; border-bottom: 1px solid #d9d7e8; }
.membership-steps li:first-child { padding-top: 0; }
.membership-steps li:last-child { border-bottom: 0; padding-bottom: 0; }
.membership-step-number { padding-top: .15rem; color: var(--blue-deep); font-size: .85rem; font-weight: 750; font-variant-numeric: tabular-nums; }
.membership-steps h3 { margin: 0 0 .65rem; font-size: 1.2rem; }
.membership-steps p { margin: 0; color: var(--muted); font-size: .95rem; line-height: 1.8; }
@media (max-width: 820px) { .membership-inner { grid-template-columns: 1fr; } }