:root {
  --navy: #10192f;
  --navy-2: #182540;
  --blue: #59b6f8;
  --ice: #eaf7ff;
  --white: #fff;
  --paper: #f7fbff;
  --soft: #5b667d;
  --line: rgba(16, 25, 47, .13);
  --shadow: 0 24px 70px rgba(16, 25, 47, .14);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--navy); background: var(--paper); font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; font-size: 16px; line-height: 1.55; }
img { display: block; max-width: 100%; }
a { color: inherit; }
:focus-visible { outline: 3px solid var(--blue); outline-offset: 4px; }

.topbar { width: min(1180px, calc(100% - 40px)); height: 78px; margin: auto; display: flex; align-items: center; justify-content: space-between; }
.brand { display: inline-flex; align-items: center; gap: .7rem; color: var(--navy); text-decoration: none; font-weight: 950; letter-spacing: -.03em; }
.brand-mark { width: 38px; height: 38px; display: grid; place-items: center; border-radius: 12px; background: var(--navy); color: var(--blue); }
.secure-note { color: var(--soft); font-size: .88rem; font-weight: 750; }
.lock { display: inline-grid; width: 25px; height: 25px; margin-right: .35rem; place-items: center; border-radius: 50%; background: var(--ice); color: var(--navy); }

.checkout-hero { width: min(1180px, calc(100% - 40px)); margin: 1.5rem auto 6rem; display: grid; grid-template-columns: 1.08fr .92fr; gap: clamp(2rem, 6vw, 5rem); align-items: start; }
.offer-panel { padding-top: 2rem; }
.eyebrow, .overline { margin: 0 0 1rem; color: var(--soft); font-size: .76rem; font-weight: 900; letter-spacing: .12em; text-transform: uppercase; }
.eyebrow::before { content: ""; display: inline-block; width: 28px; height: 3px; margin: 0 .6rem .18rem 0; border-radius: 99px; background: var(--blue); }
h1, h2, h3, p { margin-top: 0; }
h1 { max-width: 720px; margin-bottom: 1.25rem; font-size: clamp(3.2rem, 6.7vw, 6rem); line-height: .92; letter-spacing: -.068em; }
h1 em { color: var(--blue); font-family: Georgia, "Times New Roman", serif; font-weight: 500; }
.lead { max-width: 650px; color: var(--soft); font-size: 1.1rem; }

.course-visual-wrap { position: relative; margin: 2.4rem 0; }
.course-visual { width: 100%; aspect-ratio: 5 / 4; object-fit: cover; border-radius: 28px; box-shadow: var(--shadow); }
.instant-badge { position: absolute; right: 1rem; bottom: 1rem; padding: .65rem .9rem; border-radius: 999px; background: rgba(255,255,255,.92); box-shadow: 0 8px 24px rgba(16,25,47,.13); font-size: .82rem; font-weight: 850; backdrop-filter: blur(10px); }
.included-grid { display: grid; grid-template-columns: repeat(2, 1fr); border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.included-grid > div { min-height: 110px; display: grid; grid-template-columns: 34px 1fr; align-content: center; padding: 1rem; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--white); }
.included-grid span { grid-row: span 2; color: var(--blue); font-weight: 950; }
.included-grid strong { font-size: .95rem; }
.included-grid small { color: var(--soft); }

.payment-card { position: sticky; top: 24px; padding: clamp(1.25rem, 3vw, 2rem); border: 1px solid var(--line); border-radius: 28px; background: var(--white); box-shadow: var(--shadow); }
.payment-heading { display: flex; justify-content: space-between; gap: 1.5rem; align-items: start; padding-bottom: 1.35rem; border-bottom: 1px solid var(--line); }
.payment-heading h2 { max-width: 280px; margin: 0; font-size: 1.35rem; line-height: 1.15; letter-spacing: -.035em; }
.overline { margin-bottom: .45rem; }
.pricing { display: grid; grid-template-columns: auto auto; justify-content: end; align-items: baseline; column-gap: .45rem; text-align: right; }
.pricing del { grid-column: 1 / -1; color: #8b93a4; font-weight: 750; }
.pricing strong { font-size: 2.8rem; line-height: 1; letter-spacing: -.07em; }
.pricing span { color: var(--soft); font-size: .72rem; font-weight: 850; }
.launch-banner { display: flex; justify-content: space-between; gap: 1rem; margin: 1rem 0; padding: .78rem .9rem; border-radius: 13px; background: var(--ice); font-size: .84rem; }
.launch-banner span { color: var(--soft); }

.preview-alert { margin-bottom: 1rem; padding: .75rem .8rem; border: 1px dashed rgba(16,25,47,.28); border-radius: 12px; background: #fbfdff; color: var(--soft); font-size: .78rem; }
.preview-alert span { margin-right: .4rem; padding: .2rem .4rem; border-radius: 6px; background: var(--navy); color: var(--white); font-weight: 850; text-transform: uppercase; }
.field-group { margin-top: .9rem; }
.field-label { display: block; margin-bottom: .38rem; font-size: .8rem; font-weight: 800; }
.field-shell, .card-shell { border: 1px solid #cfd5df; border-radius: 10px; background: #f9fafc; color: #9299a7; }
.field-shell { min-height: 48px; display: flex; align-items: center; padding: .8rem .9rem; }
.card-number, .card-details { min-height: 48px; display: flex; align-items: center; justify-content: space-between; padding: .8rem .9rem; }
.card-number { border-bottom: 1px solid #cfd5df; }
.card-details span { width: 50%; }
.card-details span + span { padding-left: .9rem; border-left: 1px solid #cfd5df; }
.card-brands { color: var(--navy); font-size: .72rem; font-weight: 900; }
.split-fields { display: grid; grid-template-columns: 1fr 1fr; gap: .7rem; }
.purchase-button { min-height: 56px; display: flex; align-items: center; justify-content: space-between; gap: 1rem; margin-top: 1.25rem; padding: .85rem 1.1rem; border-radius: 13px; background: var(--navy); color: var(--white); text-decoration: none; font-weight: 850; box-shadow: 0 15px 30px rgba(16,25,47,.22); transition: transform .2s ease, box-shadow .2s ease; }
.purchase-button:hover { transform: translateY(-2px); box-shadow: 0 19px 36px rgba(16,25,47,.27); }
.purchase-button strong { font-size: 1.1rem; }
.payment-footnote { margin: .75rem .25rem 0; color: var(--soft); text-align: center; font-size: .75rem; }
.purchase-points { display: grid; gap: .5rem; margin: 1.25rem 0 0; padding: 1.1rem 0 0; border-top: 1px solid var(--line); list-style: none; color: var(--soft); font-size: .84rem; }
.purchase-points span { color: #1f8b4c; font-weight: 950; }

.course-summary, .faq-section { width: min(1050px, calc(100% - 40px)); margin: 0 auto; padding: 5rem 0; }
.course-summary { display: grid; grid-template-columns: 1.1fr .9fr; gap: 4rem; border-top: 1px solid var(--line); }
.course-summary h2, .faq-section h2 { margin-bottom: 0; font-size: clamp(2.3rem, 5vw, 4.5rem); line-height: .98; letter-spacing: -.055em; }
.summary-copy { color: var(--soft); font-size: 1.05rem; }
.faq-section { padding-top: 2rem; }
.faq-section h2 { margin-bottom: 2rem; }
.faq-list { border-top: 1px solid var(--line); }
details { border-bottom: 1px solid var(--line); }
summary { position: relative; padding: 1.25rem 3rem 1.25rem 0; cursor: pointer; list-style: none; font-weight: 850; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; position: absolute; right: .25rem; top: 1rem; color: var(--blue); font-size: 1.45rem; }
details[open] summary::after { content: "−"; }
details p { max-width: 720px; padding: 0 2rem 1.2rem 0; color: var(--soft); }
footer { min-height: 90px; display: flex; justify-content: space-between; align-items: center; gap: 1rem; padding: 1.5rem max(20px, calc((100vw - 1180px) / 2)); border-top: 1px solid var(--line); background: var(--white); color: var(--soft); }
footer strong { color: var(--navy); }

.course-app { min-height: 100vh; background: #f4f7fb; }
.course-shell { min-height: 100vh; display: grid; grid-template-columns: 310px 1fr; }
.course-sidebar { position: sticky; top: 0; height: 100vh; display: flex; flex-direction: column; padding: 1.25rem; background: var(--navy); color: var(--white); overflow-y: auto; }
.course-sidebar .brand { color: var(--white); margin-bottom: 2rem; }
.course-sidebar .brand-mark { background: var(--white); color: var(--navy); }
.course-title { margin-bottom: .45rem; font-size: 1.1rem; line-height: 1.2; }
.progress-label { display: flex; justify-content: space-between; gap: 1rem; color: #aab7cf; font-size: .77rem; }
.progress-track { height: 7px; margin: .55rem 0 1.5rem; border-radius: 999px; background: rgba(255,255,255,.13); overflow: hidden; }
.progress-fill { width: 0; height: 100%; background: var(--blue); transition: width .25s ease; }
.module-nav { display: grid; gap: .6rem; }
.module-group { padding: .7rem; border: 1px solid rgba(255,255,255,.1); border-radius: 14px; }
.module-name { margin: 0 0 .5rem; color: #dce6f8; font-size: .76rem; font-weight: 900; letter-spacing: .055em; text-transform: uppercase; }
.lesson-button { width: 100%; display: flex; align-items: center; gap: .7rem; padding: .65rem .55rem; border: 0; border-radius: 9px; background: transparent; color: #aab7cf; text-align: left; font: inherit; font-size: .84rem; cursor: pointer; }
.lesson-button:hover, .lesson-button.active { background: rgba(255,255,255,.09); color: var(--white); }
.lesson-dot { flex: 0 0 18px; height: 18px; display: grid; place-items: center; border: 1px solid rgba(255,255,255,.28); border-radius: 50%; font-size: .64rem; }
.lesson-button.complete .lesson-dot { border-color: var(--blue); background: var(--blue); color: var(--navy); }
.back-link { margin-top: auto; padding-top: 1.5rem; color: #aab7cf; text-decoration: none; font-size: .84rem; }
.back-link:hover { color: var(--white); }
.course-main { min-width: 0; }
.course-header { min-height: 76px; display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: 1rem clamp(1rem, 4vw, 3rem); border-bottom: 1px solid var(--line); background: rgba(255,255,255,.9); backdrop-filter: blur(12px); }
.course-header strong { font-size: .92rem; }
.course-header span { color: var(--soft); font-size: .82rem; }
.student-chip { padding: .55rem .8rem; border-radius: 999px; background: var(--ice); font-weight: 800; }
.lesson-layout { width: min(980px, calc(100% - 40px)); margin: 2.2rem auto 5rem; }
.lesson-breadcrumb { margin-bottom: .6rem; color: var(--soft); font-size: .8rem; font-weight: 800; }
.lesson-layout h1 { margin-bottom: 1.2rem; font-size: clamp(2.2rem, 5vw, 4rem); line-height: 1; }
.video-frame { position: relative; aspect-ratio: 16 / 9; display: grid; place-items: center; border-radius: 22px; background: linear-gradient(145deg, #14203c, #0a1122); color: var(--white); overflow: hidden; box-shadow: var(--shadow); }
.video-frame::before { content: ""; position: absolute; width: 480px; height: 480px; border-radius: 50%; background: radial-gradient(circle, rgba(89,182,248,.22), transparent 67%); }
.video-placeholder { position: relative; z-index: 1; display: grid; place-items: center; text-align: center; }
.play-icon { width: 70px; height: 70px; display: grid; place-items: center; margin-bottom: .9rem; border-radius: 50%; background: var(--white); color: var(--navy); font-size: 1.45rem; box-shadow: 0 12px 30px rgba(0,0,0,.25); }
.video-placeholder strong { font-size: 1rem; }
.video-placeholder small { display: block; margin-top: .3rem; color: #aab7cf; }
.lesson-content { display: grid; grid-template-columns: 1fr 280px; gap: 2rem; margin-top: 1.6rem; }
.lesson-description, .lesson-resources { padding: 1.35rem; border: 1px solid var(--line); border-radius: 18px; background: var(--white); }
.lesson-description h2, .lesson-resources h2 { margin-bottom: .65rem; font-size: 1.1rem; }
.lesson-description p { margin-bottom: 0; color: var(--soft); }
.resource-link { display: flex; justify-content: space-between; gap: 1rem; padding: .75rem 0; border-top: 1px solid var(--line); color: var(--navy); text-decoration: none; font-size: .84rem; font-weight: 800; }
.resource-link:first-of-type { margin-top: .7rem; }
.lesson-actions { display: flex; justify-content: space-between; gap: 1rem; margin-top: 1.5rem; }
.course-button { min-height: 48px; display: inline-flex; align-items: center; justify-content: center; padding: .75rem 1rem; border: 0; border-radius: 11px; background: var(--navy); color: var(--white); font: inherit; font-weight: 850; cursor: pointer; }
.course-button.secondary { border: 1px solid var(--line); background: var(--white); color: var(--navy); }
.mobile-course-menu { display: none; }

@media (max-width: 900px) {
  .checkout-hero, .course-summary { grid-template-columns: 1fr; }
  .payment-card { position: static; }
  .course-shell { grid-template-columns: 1fr; }
  .course-sidebar { position: fixed; z-index: 20; left: 0; top: 0; width: min(330px, 88vw); transform: translateX(-105%); transition: transform .22s ease; }
  .course-sidebar.open { transform: translateX(0); box-shadow: 20px 0 50px rgba(0,0,0,.25); }
  .mobile-course-menu { display: inline-flex; min-width: 44px; min-height: 44px; align-items: center; justify-content: center; border: 1px solid var(--line); border-radius: 10px; background: var(--white); font-size: 1.2rem; cursor: pointer; }
}

@media (max-width: 620px) {
  .topbar, .checkout-hero, .course-summary, .faq-section { width: min(100% - 28px, 1180px); }
  .secure-note { font-size: 0; }
  .secure-note .lock { margin: 0; font-size: .88rem; }
  .offer-panel { padding-top: .5rem; }
  h1 { font-size: clamp(3rem, 15vw, 4.8rem); }
  .included-grid, .split-fields { grid-template-columns: 1fr; }
  .payment-heading { align-items: center; }
  .course-summary { gap: 1.4rem; }
  footer { flex-direction: column; align-items: flex-start; }
  .course-header { padding: .8rem 1rem; }
  .course-header > div:nth-child(2) { display: none; }
  .lesson-layout { width: min(100% - 28px, 980px); margin-top: 1.4rem; }
  .lesson-content { grid-template-columns: 1fr; }
  .lesson-actions { flex-direction: column-reverse; }
  .course-button { width: 100%; }
}

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