:root {
  --ink: #07111d;
  --ink-soft: #0b1929;
  --panel: #0e1d2e;
  --panel-light: #13263b;
  --line: rgba(150, 186, 214, 0.18);
  --line-strong: rgba(150, 186, 214, 0.32);
  --text: #f1f7fb;
  --muted: #99aec2;
  --dim: #6d849b;
  --mint: #73f5dc;
  --blue: #73a9ff;
  --orange: #ffbd7a;
  --lilac: #b996ff;
  --shadow: 0 24px 70px rgba(0, 0, 0, 0.24);
  --radius-lg: 28px;
  --radius-md: 18px;
  --radius-sm: 11px;
  color-scheme: dark;
  font-family: "Avenir Next", "Segoe UI", system-ui, -apple-system, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background:
    radial-gradient(circle at 9% 6%, rgba(115, 245, 220, 0.07), transparent 28rem),
    radial-gradient(circle at 91% 16%, rgba(115, 169, 255, 0.08), transparent 32rem),
    var(--ink);
  color: var(--text);
  line-height: 1.55;
  font-size: 16px;
  min-width: 300px;
}

a { color: inherit; text-decoration: none; }
button, a { -webkit-tap-highlight-color: transparent; }
button { font: inherit; }
:focus-visible { outline: 3px solid var(--mint); outline-offset: 4px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.skip-link { position: fixed; left: 18px; top: 12px; padding: 10px 14px; background: var(--mint); color: var(--ink); border-radius: 8px; transform: translateY(-160%); z-index: 20; font-weight: 700; }
.skip-link:focus { transform: translateY(0); }

.section-shell { width: min(1160px, calc(100% - 48px)); margin-inline: auto; }
.site-header { position: sticky; top: 0; z-index: 10; border-bottom: 1px solid rgba(160, 196, 222, 0.1); background: rgba(7, 17, 29, 0.84); backdrop-filter: blur(18px); }
.nav-shell { width: min(1240px, calc(100% - 48px)); margin-inline: auto; min-height: 76px; display: flex; align-items: center; justify-content: space-between; gap: 22px; }
.brand { display: inline-flex; align-items: center; gap: 11px; font-weight: 760; letter-spacing: -0.02em; }
.brand-mark { width: 33px; height: 33px; display: grid; place-items: center; border: 1px solid rgba(115, 245, 220, 0.55); border-radius: 10px; color: var(--mint); font-size: 11px; letter-spacing: -0.06em; box-shadow: 0 0 24px rgba(115, 245, 220, 0.12); }
.brand-mark.small { width: 25px; height: 25px; border-radius: 7px; font-size: 9px; margin-right: 7px; vertical-align: -7px; }
.site-nav { display: flex; gap: 30px; color: var(--muted); font-size: 13px; }
.site-nav a { transition: color 160ms ease; }
.site-nav a:hover { color: var(--text); }
.nav-cta { border: 1px solid var(--line-strong); padding: 10px 14px; border-radius: 10px; font-size: 13px; color: var(--mint); transition: border-color 160ms ease, background 160ms ease; }
.nav-cta:hover { border-color: var(--mint); background: rgba(115, 245, 220, 0.07); }

.hero { min-height: 650px; display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(360px, .95fr); align-items: center; gap: 72px; padding-block: 92px 76px; }
.hero-copy { max-width: 600px; }
.eyebrow { margin: 0 0 17px; color: var(--mint); text-transform: uppercase; letter-spacing: .18em; font-size: 11px; font-weight: 760; }
.pulse-dot { display: inline-block; width: 7px; height: 7px; border-radius: 50%; background: var(--mint); box-shadow: 0 0 0 5px rgba(115, 245, 220, 0.12), 0 0 18px var(--mint); margin-right: 8px; vertical-align: 1px; }
h1, h2, h3, p { margin-top: 0; }
h1 { max-width: 710px; font-size: clamp(4.3rem, 10vw, 8.2rem); line-height: .86; letter-spacing: -.085em; margin-bottom: 31px; font-weight: 750; }
.accent-dot { color: var(--mint); }
.hero-lede { max-width: 535px; color: var(--muted); font-size: 20px; line-height: 1.5; margin-bottom: 32px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.button { display: inline-flex; align-items: center; justify-content: center; gap: 16px; min-height: 48px; padding: 12px 18px; border-radius: 11px; font-size: 14px; font-weight: 760; transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease, background 180ms ease; }
.button:hover { transform: translateY(-2px); }
.button-primary { background: var(--mint); color: var(--ink); box-shadow: 0 13px 25px rgba(115, 245, 220, 0.16); }
.button-primary:hover { box-shadow: 0 16px 32px rgba(115, 245, 220, 0.28); }
.button-quiet { color: var(--text); border: 1px solid var(--line-strong); }
.button-quiet:hover { border-color: var(--mint); background: rgba(115, 245, 220, .06); }
.micro-note { color: var(--dim); margin: 28px 0 0; font-size: 12px; }
.micro-note span { color: var(--orange); margin-right: 6px; }

.hero-visual { min-height: 485px; position: relative; display: grid; place-items: center; isolation: isolate; }
.hero-orbit { position: absolute; border: 1px solid rgba(115, 245, 220, .18); border-radius: 50%; transform: rotate(-14deg); }
.orbit-one { width: 460px; height: 190px; }
.orbit-two { width: 370px; height: 150px; border-color: rgba(115, 169, 255, .19); transform: rotate(36deg); }
.wheel-illustration { width: min(100%, 420px); position: relative; z-index: 1; filter: drop-shadow(0 24px 32px rgba(0, 0, 0, .3)); animation: float 5s ease-in-out infinite; }
.telemetry { position: absolute; z-index: 2; display: flex; flex-direction: column; gap: 3px; padding: 11px 13px; border: 1px solid var(--line); border-radius: 10px; background: rgba(11, 25, 41, .76); backdrop-filter: blur(12px); box-shadow: var(--shadow); }
.telemetry span { color: var(--dim); font-size: 9px; letter-spacing: .16em; }
.telemetry strong { color: var(--mint); font-size: 12px; letter-spacing: .08em; }
.telemetry-top { top: 56px; left: 4%; }
.telemetry-bottom { bottom: 59px; right: 5%; }
.visual-caption { position: absolute; bottom: 5px; display: flex; align-items: center; gap: 9px; color: var(--dim); font-size: 11px; letter-spacing: .08em; text-transform: uppercase; }
.caption-line { width: 25px; height: 1px; background: var(--orange); }
@keyframes float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-7px); } }

.safety-strip { border-block: 1px solid rgba(255, 189, 122, .18); background: linear-gradient(90deg, rgba(255, 189, 122, .11), rgba(255, 189, 122, .03)); }
.safety-strip-inner { min-height: 126px; display: grid; grid-template-columns: auto minmax(260px, .9fr) minmax(280px, 1fr); gap: 22px; align-items: center; }
.safety-icon { width: 44px; height: 44px; border: 1px solid var(--orange); border-radius: 50%; display: grid; place-items: center; color: var(--orange); font-weight: 800; font-size: 20px; }
.safety-strip .eyebrow { color: var(--orange); margin-bottom: 6px; }
.safety-strip h2 { font-size: clamp(1.3rem, 2.4vw, 1.8rem); line-height: 1.1; letter-spacing: -.04em; margin-bottom: 0; }
.safety-strip-copy { color: var(--muted); margin: 0; font-size: 14px; }

.readiness, .lesson, .mistakes, .progression, .final-callout { padding-block: 112px; }
.section-heading { margin-bottom: 40px; }
.section-heading h2 { font-size: clamp(2.2rem, 5vw, 4.2rem); line-height: .98; letter-spacing: -.065em; margin-bottom: 0; max-width: 720px; }
.section-heading > p, .split-heading > p { color: var(--muted); max-width: 365px; font-size: 14px; line-height: 1.65; margin: 8px 0 0; }
.split-heading { display: grid; grid-template-columns: minmax(0, 1fr) 330px; gap: 30px; align-items: end; }
.readiness-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
.readiness-card { position: relative; min-height: 245px; padding: 28px 26px; border: 1px solid var(--line); border-radius: var(--radius-md); background: linear-gradient(145deg, rgba(19, 38, 59, .83), rgba(13, 28, 44, .73)); overflow: hidden; }
.readiness-card::after { content: ""; position: absolute; width: 110px; height: 110px; right: -35px; bottom: -45px; border: 1px solid rgba(115, 245, 220, .2); border-radius: 50%; }
.readiness-index { color: var(--orange); font-size: 11px; letter-spacing: .14em; }
.readiness-card-icon { color: var(--mint); font-size: 31px; margin-block: 25px 15px; }
.readiness-card h3 { margin-bottom: 8px; font-size: 17px; letter-spacing: -.025em; }
.readiness-card p { color: var(--muted); font-size: 13px; line-height: 1.65; margin: 0; }

.lesson { border-top: 1px solid var(--line); }
.lesson-heading { display: grid; grid-template-columns: minmax(0, 1fr) 315px; gap: 40px; align-items: end; }
.progress-panel { border: 1px solid var(--line-strong); border-radius: var(--radius-md); background: var(--panel); padding: 23px 25px 19px; margin-bottom: 22px; box-shadow: 0 20px 50px rgba(0, 0, 0, .16); }
.progress-panel-top, .progress-meta { display: flex; justify-content: space-between; align-items: center; gap: 20px; }
.progress-kicker { display: block; color: var(--dim); font-size: 10px; letter-spacing: .16em; text-transform: uppercase; margin-bottom: 4px; }
.progress-panel strong { font-size: 15px; letter-spacing: -.02em; }
.text-button { padding: 4px 0; border: 0; color: var(--muted); background: transparent; font-size: 12px; cursor: pointer; text-decoration: underline; text-underline-offset: 3px; }
.text-button:hover { color: var(--mint); }
.progress-track { height: 6px; background: #1a2d43; border-radius: 999px; overflow: hidden; margin: 18px 0 9px; }
#progress-fill { display: block; width: 0; height: 100%; border-radius: inherit; background: linear-gradient(90deg, var(--mint), var(--blue)); transition: width 300ms ease; }
.progress-meta { color: var(--dim); font-size: 11px; }
#progress-percent { color: var(--mint); font-weight: 700; }
.lesson-grid { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; counter-reset: steps; }
.lesson-grid > li { min-width: 0; }
.lesson-card { height: 100%; display: flex; flex-direction: column; border: 1px solid var(--line); border-radius: var(--radius-md); background: linear-gradient(150deg, rgba(14, 29, 46, .95), rgba(9, 20, 33, .92)); padding: 21px 22px 19px; transition: border-color 180ms ease, background 180ms ease, transform 180ms ease; }
.lesson-card:hover { border-color: rgba(115, 245, 220, .42); transform: translateY(-2px); }
.lesson-card.is-next { border-color: rgba(115, 245, 220, .65); box-shadow: 0 0 0 1px rgba(115, 245, 220, .12), 0 18px 38px rgba(0, 0, 0, .17); }
.lesson-card.is-complete { border-color: rgba(115, 245, 220, .35); background: linear-gradient(150deg, rgba(17, 44, 52, .9), rgba(9, 26, 37, .92)); }
.lesson-card-top { display: flex; justify-content: space-between; align-items: center; margin-bottom: 17px; }
.step-number { color: var(--orange); font-size: 12px; letter-spacing: .12em; }
.step-tag { padding: 4px 8px; border: 1px solid var(--line); border-radius: 999px; color: var(--dim); font-size: 10px; text-transform: uppercase; letter-spacing: .08em; }
.lesson-card-body { display: grid; grid-template-columns: minmax(0, 1fr) 160px; gap: 13px; align-items: center; min-height: 170px; }
.lesson-card h3 { font-size: 21px; letter-spacing: -.04em; line-height: 1.1; margin-bottom: 10px; }
.lesson-card p { color: var(--muted); font-size: 13px; line-height: 1.65; margin-bottom: 0; }
.step-diagram { width: 100%; height: auto; max-height: 136px; }
.coach-tip { border-top: 1px solid var(--line); margin-top: 14px; padding-top: 13px; font-size: 11px !important; color: var(--dim) !important; }
.coach-tip span { color: var(--orange); font-size: 9px; letter-spacing: .13em; margin-right: 7px; }
.step-toggle { display: inline-flex; align-items: center; gap: 8px; width: fit-content; margin-top: 16px; color: var(--text); font-size: 12px; cursor: pointer; }
.step-check { width: 18px; height: 18px; margin: 0; accent-color: var(--mint); cursor: pointer; }
.step-check:checked + span { color: var(--mint); text-decoration: line-through; text-decoration-color: rgba(115, 245, 220, .6); }

.mistakes { border-top: 1px solid var(--line); }
.mistake-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; }
.mistake-card { min-height: 190px; padding: 22px 20px; border-top: 2px solid var(--line-strong); background: rgba(14, 29, 46, .54); }
.mistake-card:nth-child(1) { border-color: var(--mint); }
.mistake-card:nth-child(2) { border-color: var(--blue); }
.mistake-card:nth-child(3) { border-color: var(--orange); }
.mistake-card:nth-child(4) { border-color: var(--lilac); }
.mistake-symbol { display: block; color: var(--mint); font-size: 26px; line-height: 1; margin-bottom: 22px; }
.mistake-card:nth-child(2) .mistake-symbol { color: var(--blue); }
.mistake-card:nth-child(3) .mistake-symbol { color: var(--orange); }
.mistake-card:nth-child(4) .mistake-symbol { color: var(--lilac); }
.mistake-card h3 { font-size: 15px; margin-bottom: 7px; }
.mistake-card p { color: var(--muted); font-size: 12px; line-height: 1.6; margin: 0; }

.progression { border-top: 1px solid var(--line); }
.progression-timeline { list-style: none; padding: 0; margin: 12px 0 0; position: relative; }
.progression-timeline::before { content: ""; position: absolute; top: 0; bottom: 0; left: 27px; width: 1px; background: linear-gradient(var(--mint), rgba(115, 245, 220, .07)); }
.progression-item { position: relative; display: grid; grid-template-columns: 56px minmax(0, 1fr); gap: 27px; padding: 24px 0; }
.progression-marker { position: relative; z-index: 1; width: 56px; height: 56px; display: grid; place-items: center; border: 1px solid rgba(115, 245, 220, .45); border-radius: 50%; background: var(--ink); color: var(--mint); font-size: 12px; }
.progression-content { padding: 4px 0 0; max-width: 710px; }
.progression-meta { display: flex; gap: 20px; color: var(--orange); font-size: 10px; text-transform: uppercase; letter-spacing: .13em; margin-bottom: 10px; }
.progression-content h3 { margin-bottom: 6px; font-size: 24px; letter-spacing: -.04em; }
.progression-content p { color: var(--muted); font-size: 14px; margin-bottom: 0; }

.final-callout { padding-top: 42px; padding-bottom: 112px; }
.final-callout-inner { display: flex; align-items: center; justify-content: space-between; gap: 30px; padding: 38px 40px; border: 1px solid rgba(115, 245, 220, .28); border-radius: var(--radius-lg); background: radial-gradient(circle at 70% 20%, rgba(115, 245, 220, .1), transparent 24rem), var(--panel); }
.final-callout .eyebrow { margin-bottom: 9px; }
.final-callout h2 { margin-bottom: 10px; font-size: clamp(2rem, 4vw, 3.25rem); line-height: .95; letter-spacing: -.06em; }
.final-callout p:not(.eyebrow) { max-width: 550px; color: var(--muted); font-size: 14px; margin-bottom: 0; }
.site-footer { border-top: 1px solid var(--line); padding-block: 25px 30px; }
.footer-inner { display: flex; justify-content: space-between; gap: 30px; align-items: center; color: var(--dim); font-size: 11px; }
.footer-inner p { margin: 0; }
.footer-inner > p:first-child { color: var(--text); font-weight: 700; }
.footer-note { max-width: 570px; text-align: right; }

@media (max-width: 900px) {
  .hero { grid-template-columns: 1fr; gap: 20px; padding-top: 68px; }
  .hero-copy { max-width: 700px; }
  .hero-visual { min-height: 400px; }
  .safety-strip-inner { grid-template-columns: auto minmax(0, 1fr); padding-block: 25px; }
  .safety-strip-copy { grid-column: 2; }
  .lesson-card-body { grid-template-columns: minmax(0, 1fr) 145px; }
  .mistake-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 680px) {
  .section-shell, .nav-shell { width: min(100% - 32px, 540px); }
  .site-header { position: relative; }
  .nav-shell { min-height: 68px; }
  .site-nav { display: none; }
  .nav-cta { margin-left: auto; }
  .hero { min-height: auto; padding-block: 62px 56px; }
  h1 { font-size: clamp(4rem, 20vw, 6.2rem); }
  .hero-lede { font-size: 17px; }
  .hero-visual { min-height: 320px; }
  .orbit-one { width: 350px; height: 150px; }
  .orbit-two { width: 290px; height: 125px; }
  .telemetry-top { top: 16px; left: 0; }
  .telemetry-bottom { bottom: 22px; right: 0; }
  .wheel-illustration { width: min(100%, 340px); }
  .safety-strip-inner { grid-template-columns: auto 1fr; gap: 14px; }
  .safety-strip h2 { font-size: 1.3rem; }
  .safety-strip-copy { grid-column: 1 / -1; margin-left: 58px; }
  .readiness, .lesson, .mistakes, .progression { padding-block: 78px; }
  .final-callout { padding-block: 14px 78px; }
  .split-heading, .lesson-heading { display: block; }
  .section-heading > p, .split-heading > p { margin-top: 20px; }
  .readiness-grid, .lesson-grid, .mistake-grid { grid-template-columns: 1fr; }
  .readiness-card { min-height: 210px; }
  .lesson-card-body { grid-template-columns: minmax(0, 1fr) 125px; min-height: 155px; }
  .progress-panel { padding: 19px; }
  .final-callout-inner { display: block; padding: 28px 24px; }
  .final-callout .button { margin-top: 26px; }
  .footer-inner { display: block; }
  .footer-note { text-align: left; margin-top: 14px !important; }
}

@media (max-width: 420px) {
  .brand > span:last-child { display: none; }
  .lesson-card-body { display: block; }
  .step-diagram { display: block; width: 150px; margin: 12px auto 0; }
  .progression-item { grid-template-columns: 44px minmax(0, 1fr); gap: 18px; }
  .progression-timeline::before { left: 21px; }
  .progression-marker { width: 44px; height: 44px; }
}

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