:root {
  color-scheme: light;
  --ink: #122e32;
  --ink-soft: #385256;
  --muted: #66797b;
  --deep: #092c31;
  --deep-2: #0f4145;
  --gold: #e5ae27;
  --gold-light: #ffd772;
  --mint: #e8f3f0;
  --paper: #f7f8f5;
  --white: #fff;
  --line: #dce5e1;
  --shadow: 0 24px 70px rgba(11, 39, 42, .12);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
}

* { box-sizing: border-box; }
body { margin: 0; min-width: 320px; color: var(--ink); background: var(--paper); line-height: 1.65; }
a { color: inherit; }
a:focus-visible, summary:focus-visible { outline: 3px solid var(--gold); outline-offset: 4px; border-radius: 3px; }
.site-header { min-height: 82px; display: flex; align-items: center; justify-content: space-between; gap: 28px; padding: 12px clamp(20px, 6vw, 90px); background: var(--white); border-bottom: 1px solid rgba(9, 44, 49, .08); }
.brand { display: inline-flex; align-items: center; width: min(230px, 46vw); }
.brand img { display: block; width: 100%; height: auto; }
.header-nav { display: flex; align-items: center; gap: clamp(14px, 2.8vw, 38px); font-size: 13px; font-weight: 650; }
.header-nav a, .site-footer a { text-decoration: none; }
.header-nav a:not(.nav-cta):hover, .site-footer a:hover, .back-link:hover { color: #956c0b; }
.nav-cta { padding: 10px 17px; border-radius: 999px; background: var(--deep); color: var(--white); }
.nav-cta:hover { background: var(--deep-2); }
.hero { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(340px, .9fr); gap: clamp(32px, 7vw, 100px); align-items: center; min-height: 570px; padding: 70px clamp(20px, 9vw, 140px) 78px; overflow: hidden; color: var(--white); background: radial-gradient(ellipse at 83% 30%, rgba(31, 102, 91, .8), transparent 40%), linear-gradient(125deg, #082a30 0%, #0c4143 58%, #173e3a 100%); }
.hero-copy { max-width: 750px; position: relative; z-index: 1; }
.eyebrow { margin: 0 0 14px; color: #b88713; font-size: 11px; font-weight: 800; letter-spacing: .17em; text-transform: uppercase; }
.hero .eyebrow, .course-hero .eyebrow { color: var(--gold-light); }
h1, h2, h3, p { margin-top: 0; }
.hero h1 { margin: 0; font-size: clamp(42px, 6.5vw, 78px); line-height: 1.04; letter-spacing: -.055em; }
.hero h1 span { color: var(--gold-light); }
.hero-lede { max-width: 640px; margin: 24px 0 28px; color: rgba(255,255,255,.8); font-size: clamp(16px, 1.8vw, 19px); }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.button { display: inline-flex; align-items: center; justify-content: center; gap: 13px; min-height: 48px; padding: 12px 20px; border-radius: 999px; font-size: 13px; font-weight: 750; text-decoration: none; transition: transform .18s ease, background .18s ease; }
.button:hover { transform: translateY(-2px); }
.button-primary { color: var(--deep); background: var(--gold-light); }
.button-primary:hover { background: #ffe39a; }
.button-ghost { border: 1px solid rgba(255,255,255,.35); color: var(--white); background: rgba(255,255,255,.04); }
.button-ghost:hover { background: rgba(255,255,255,.11); }
.button-light { color: var(--deep); background: var(--white); white-space: nowrap; }
.button-light:hover { background: #edf4f1; }
.status-row { display: flex; flex-wrap: wrap; align-items: center; gap: 10px 18px; margin-top: 32px; color: rgba(255,255,255,.72); font-size: 11px; }
.status-pill { display: inline-flex; align-items: center; gap: 7px; color: #fff; }
.status-pill i { width: 7px; height: 7px; border-radius: 50%; background: var(--gold-light); box-shadow: 0 0 0 4px rgba(255,215,114,.13); }
.hero-art { min-height: 335px; position: relative; display: grid; place-items: center; }
.hero-art::before { content: ""; position: absolute; width: min(34vw, 400px); aspect-ratio: 1; border: 1px solid rgba(240,208,124,.23); border-radius: 50%; box-shadow: 0 0 0 28px rgba(240,208,124,.035), 0 0 0 64px rgba(240,208,124,.025); }
.hero-art::after { content: ""; position: absolute; width: 100%; height: 1px; top: 54%; left: 0; background: linear-gradient(90deg, transparent, rgba(255,215,114,.4), transparent); transform: rotate(-22deg); }
.ore-orb { position: absolute; border-radius: 48% 52% 63% 37% / 42% 40% 60% 58%; transform: rotate(25deg); filter: drop-shadow(0 30px 24px rgba(0,0,0,.25)); }
.orb-one { width: 135px; height: 165px; top: 39px; right: 21%; background: linear-gradient(135deg, #ffdc7d, #b87613 54%, #653f11); clip-path: polygon(50% 0, 91% 27%, 100% 73%, 62% 100%, 16% 84%, 0 40%); }
.orb-two { width: 75px; height: 90px; bottom: 90px; left: 18%; background: linear-gradient(130deg, #e9bf5c, #744b18); clip-path: polygon(48% 0, 92% 21%, 100% 68%, 66% 100%, 15% 75%, 0 28%); }
.process-card { position: relative; z-index: 1; width: min(100%, 420px); margin-top: 130px; padding: 17px 20px 16px; border: 1px solid rgba(255,255,255,.19); border-radius: 14px; color: var(--white); background: rgba(5,34,37,.78); box-shadow: var(--shadow); backdrop-filter: blur(9px); }
.process-label { display: block; margin-bottom: 12px; color: var(--gold-light); font-size: 10px; font-weight: 800; letter-spacing: .14em; text-transform: uppercase; }
.process-line { display: flex; align-items: center; justify-content: space-between; gap: 6px; font-size: 11px; font-weight: 700; }
.process-line b { color: var(--gold-light); }
.process-line-bottom { margin-top: 13px; padding-top: 12px; border-top: 1px solid rgba(255,255,255,.12); color: rgba(255,255,255,.75); }
.art-caption { position: absolute; right: 0; bottom: 0; color: rgba(255,255,255,.52); font-size: 10px; letter-spacing: .08em; }
.notice-bar { display: flex; align-items: center; gap: 14px; padding: 17px clamp(20px, 9vw, 140px); border-bottom: 1px solid #d8e5df; background: #ecf5f1; }
.notice-bar p { flex: 1; margin: 0; color: #3d585a; font-size: 12px; }
.notice-bar a { color: #164d4d; font-size: 11px; font-weight: 800; text-decoration: none; white-space: nowrap; }
.notice-icon { display: grid; flex: 0 0 25px; width: 25px; height: 25px; place-items: center; border-radius: 50%; color: var(--white); background: #1d655d; font-size: 13px; font-weight: 800; }
.section-block { padding: 82px clamp(20px, 9vw, 140px); }
.section-heading { max-width: 680px; margin-bottom: 32px; }
.section-heading h2, .study-panel h2 { margin: 0 0 13px; font-size: clamp(28px, 4vw, 44px); line-height: 1.12; letter-spacing: -.04em; }
.section-heading > p:last-child, .study-panel p:not(.eyebrow) { margin: 0; color: var(--muted); font-size: 15px; }
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.feature-card { min-height: 240px; padding: 25px; border: 1px solid var(--line); border-radius: 15px; background: var(--white); transition: transform .2s ease, box-shadow .2s ease; }
.feature-card:hover { transform: translateY(-4px); box-shadow: 0 18px 45px rgba(20, 59, 58, .1); }
.feature-number { display: inline-grid; width: 32px; height: 32px; place-items: center; border-radius: 9px; color: #74540c; background: #fff2ce; font-size: 11px; font-weight: 850; }
.feature-card h3 { margin: 20px 0 8px; font-size: 18px; }
.feature-card p { min-height: 64px; margin-bottom: 16px; color: var(--muted); font-size: 13px; }
.feature-card a { color: #125b54; font-size: 12px; font-weight: 800; text-decoration: none; }
.study-panel { display: flex; align-items: center; justify-content: space-between; gap: 38px; margin: 0 clamp(20px, 9vw, 140px); padding: clamp(28px, 5vw, 54px); border-radius: 20px; color: var(--white); background: linear-gradient(120deg, #0b3638, #124e4b); }
.study-panel > div { max-width: 700px; }
.study-panel .eyebrow { color: var(--gold-light); }
.study-panel h2 { font-size: clamp(26px, 3.8vw, 39px); }
.study-panel p:not(.eyebrow) { color: rgba(255,255,255,.72); }
.next-step { display: flex; align-items: center; justify-content: space-between; gap: 30px; }
.next-step .section-heading { margin: 0; }
.site-footer { display: flex; align-items: center; justify-content: space-between; gap: 16px; margin-top: 45px; padding: 25px clamp(20px, 6vw, 90px); border-top: 1px solid var(--line); color: var(--muted); background: var(--white); font-size: 11px; }

/* Course page */
.course-header { position: sticky; z-index: 5; top: 0; }
.course-layout { display: grid; grid-template-columns: 235px minmax(0, 820px); justify-content: center; gap: clamp(34px, 6vw, 88px); padding: 45px 24px 80px; }
.course-sidebar { align-self: start; position: sticky; top: 112px; padding: 21px 0; }
.course-sidebar h2 { margin: 0 0 16px; font-size: 18px; }
.course-sidebar nav { display: grid; gap: 4px; }
.course-sidebar nav a { padding: 7px 10px; border-left: 2px solid transparent; color: var(--muted); font-size: 11px; line-height: 1.45; text-decoration: none; }
.course-sidebar nav a:hover { border-color: var(--gold); color: var(--ink); background: #edf3f0; }
.sidebar-download { display: inline-block; margin-top: 20px; color: #155d54; font-size: 11px; font-weight: 800; text-decoration: none; }
.course-content { min-width: 0; }
.back-link { color: var(--muted); font-size: 12px; font-weight: 650; text-decoration: none; }
.course-hero { margin: 28px 0 28px; padding: clamp(30px, 6vw, 65px); border-radius: 20px; color: var(--white); background: radial-gradient(ellipse at 90% 10%, rgba(51, 121, 105, .75), transparent 43%), linear-gradient(135deg, #082a30, #10514e); }
.course-hero h1 { margin: 0; font-size: clamp(39px, 7vw, 66px); line-height: 1.03; letter-spacing: -.05em; }
.course-hero h1 span { color: var(--gold-light); }
.course-hero > p:not(.eyebrow) { max-width: 680px; margin: 20px 0; color: rgba(255,255,255,.8); font-size: 16px; }
.course-meta { display: flex; flex-wrap: wrap; gap: 8px; }
.course-meta span { padding: 6px 10px; border: 1px solid rgba(255,255,255,.23); border-radius: 99px; color: rgba(255,255,255,.83); font-size: 10px; }
.editorial-note { padding: 19px 22px; border-left: 4px solid var(--gold); border-radius: 4px 12px 12px 4px; background: #fff3d0; }
.editorial-note strong { display: block; margin-bottom: 5px; color: #59440e; font-size: 13px; }
.editorial-note p { margin: 0; color: #645b43; font-size: 12px; }
.lesson { scroll-margin-top: 110px; margin-top: 22px; padding: clamp(24px, 4vw, 38px); border: 1px solid var(--line); border-radius: 15px; background: var(--white); }
.lesson-kicker { margin: 0 0 7px; color: #aa7a08; font-size: 10px; font-weight: 850; letter-spacing: .14em; text-transform: uppercase; }
.lesson h2 { margin: 0 0 15px; font-size: clamp(24px, 4vw, 32px); line-height: 1.15; letter-spacing: -.035em; }
.lesson h3 { margin: 24px 0 9px; font-size: 17px; }
.lesson p { color: #52666a; font-size: 14px; }
.lesson p:last-child { margin-bottom: 0; }
.check-list { display: grid; gap: 10px; margin: 18px 0 0; padding: 0; list-style: none; }
.check-list li { position: relative; padding-left: 26px; color: #425a5d; font-size: 13px; }
.check-list li::before { content: "✓"; position: absolute; left: 0; top: 0; color: #217261; font-weight: 900; }
.data-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; margin: 21px 0; }
.data-grid div { display: grid; gap: 5px; padding: 15px; border: 1px solid var(--line); border-radius: 10px; background: #f9fbf9; }
.data-grid strong { color: var(--ink); font-size: 12px; }
.data-grid span { color: var(--muted); font-size: 11px; }
.key-point { display: grid; gap: 5px; margin: 20px 0; padding: 18px 20px; border-left: 3px solid #1d7264; background: var(--mint); }
.key-point strong { color: #15584f; font-size: 12px; }
.key-point span { color: #496365; font-size: 12px; }
.flow-list { display: grid; grid-template-columns: repeat(5, 1fr); gap: 8px; margin: 24px 0; }
.flow-list > div { display: grid; align-content: start; gap: 11px; min-height: 140px; padding: 13px; border: 1px solid var(--line); border-radius: 10px; background: #f8faf8; }
.flow-list b { display: grid; width: 24px; height: 24px; place-items: center; border-radius: 7px; color: #70520c; background: #ffedba; font-size: 11px; }
.flow-list strong, .flow-list small { display: block; }
.flow-list strong { margin-bottom: 5px; font-size: 11px; }
.flow-list small { color: var(--muted); font-size: 10px; line-height: 1.45; }
.equation { overflow-wrap: anywhere; margin: 15px 0; padding: 18px; border: 1px solid #d7e4df; border-radius: 10px; color: #12574f; background: #eff7f3; font-family: Georgia, "Times New Roman", serif; font-size: clamp(16px, 3vw, 22px); text-align: center; }
.equation-small { font-size: 16px; }
.two-column-notes { display: grid; grid-template-columns: repeat(2,1fr); gap: 12px; margin: 20px 0; }
.two-column-notes div { padding: 17px; border-radius: 10px; background: #f3f6f3; }
.two-column-notes h3 { margin: 0 0 5px; font-size: 14px; }
.two-column-notes p { margin: 0; font-size: 12px; }
.comparison-table-wrap { overflow-x: auto; margin: 20px 0; }
table { width: 100%; border-collapse: collapse; font-size: 12px; }
th { padding: 12px; color: var(--white); background: var(--deep-2); text-align: left; }
td { padding: 12px; border-bottom: 1px solid var(--line); color: #52666a; vertical-align: top; }
tbody tr:nth-child(even) { background: #f5f8f6; }
td strong { color: var(--ink); }
.reference-cards { display: grid; grid-template-columns: repeat(2,1fr); gap: 10px; margin-top: 20px; }
.reference-cards a { display: grid; gap: 6px; padding: 16px; border: 1px solid var(--line); border-radius: 10px; text-decoration: none; }
.reference-cards a:hover { border-color: #7ca79a; background: #f6faf7; }
.reference-cards strong { color: var(--ink); font-size: 12px; }
.reference-cards span { color: var(--muted); font-size: 11px; }
.reference-cards b { color: #176257; font-size: 10px; }
.result-status-grid { display: grid; gap: 8px; margin: 20px 0; }
.result-status-grid div { display: grid; grid-template-columns: 11px 1fr; gap: 0 10px; align-items: center; padding: 12px 14px; border: 1px solid var(--line); border-radius: 9px; }
.result-status-grid strong { font-size: 12px; }
.result-status-grid small { grid-column: 2; color: var(--muted); font-size: 11px; }
.status-dot { width: 8px; height: 8px; border-radius: 50%; background: #c89b2d; }
.references-list { display: grid; gap: 11px; padding-left: 20px; color: #52666a; font-size: 12px; }
.references-list a { color: #176257; font-weight: 700; }
details { padding: 14px 0; border-bottom: 1px solid var(--line); }
details:last-child { border-bottom: 0; }
summary { color: var(--ink); font-size: 13px; font-weight: 750; cursor: pointer; }
details p { margin: 10px 0 0; font-size: 12px!important; }
.course-end { display: flex; justify-content: space-between; gap: 16px; padding: 25px 5px; }
.course-end a { color: #176257; font-size: 12px; font-weight: 750; text-decoration: none; }

@media (max-width: 850px) {
  .hero { grid-template-columns: 1fr; padding-top: 58px; }
  .hero-art { min-height: 280px; }
  .hero-art::before { width: 270px; }
  .orb-one { right: 22%; }
  .feature-grid { grid-template-columns: 1fr; }
  .feature-card { min-height: auto; }
  .feature-card p { min-height: 0; }
  .study-panel { align-items: flex-start; flex-direction: column; }
  .course-layout { width: 100%; grid-template-columns: minmax(0, 1fr); gap: 4px; max-width: 900px; margin: auto; }
  .course-sidebar { position: static; order: 0; width: 100%; min-width: 0; max-width: 100%; padding: 12px 0; }
  .course-sidebar h2 { display: none; }
  .course-sidebar nav { display: flex; width: 100%; min-width: 0; max-width: 100%; overflow-x: auto; gap: 5px; padding-bottom: 5px; }
  .course-sidebar nav a { flex: 0 0 auto; border: 1px solid var(--line); border-radius: 99px; padding: 7px 10px; background: var(--white); }
  .sidebar-download { display: none; }
  .course-content { order: 1; width: 100%; min-width: 0; max-width: 100%; }
}
@media (max-width: 600px) {
  .site-header { min-height: 68px; padding: 10px 16px; }
  .brand { width: 145px; }
  .header-nav { gap: 10px; font-size: 11px; }
  .header-nav a:first-child:not(.nav-cta), .header-nav a:nth-child(2):not(.nav-cta) { display: none; }
  .nav-cta { padding: 8px 12px; }
  .hero { padding: 48px 20px 50px; }
  .hero h1 { font-size: clamp(39px, 11vw, 58px); }
  .hero-lede { font-size: 15px; }
  .hero-art { min-height: 235px; }
  .process-card { margin-top: 95px; padding: 14px; }
  .process-line { font-size: 9px; }
  .art-caption { bottom: -5px; font-size: 9px; }
  .notice-bar { align-items: flex-start; flex-wrap: wrap; padding: 15px 20px; }
  .notice-bar p { flex-basis: calc(100% - 45px); }
  .notice-bar a { margin-left: 39px; }
  .section-block { padding: 58px 20px; }
  .study-panel { margin: 0 20px; padding: 25px; }
  .next-step { align-items: flex-start; flex-direction: column; }
  .site-footer { align-items: flex-start; flex-direction: column; padding: 22px 20px; }
  .course-layout { padding: 20px 14px 50px; }
  .course-sidebar { top: 68px; }
  .course-hero { padding: 27px 22px; }
  .course-hero h1 { font-size: clamp(34px, 10.5vw, 44px); }
  .lesson { padding: 22px 18px; }
  .data-grid, .two-column-notes, .reference-cards { grid-template-columns: 1fr; }
  .flow-list { grid-template-columns: repeat(2, 1fr); }
  .flow-list > div { min-height: 115px; }
  .flow-list > div:last-child { grid-column: 1 / -1; }
  .equation { padding: 14px 10px; }
  .course-end { font-size: 11px; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto!important; transition-duration: .01ms!important; }
}