:root {
  color-scheme: dark;
  --bg: #090d12;
  --bg2: #111827;
  --card: #141b26;
  --card2: #101722;
  --text: #eef5fb;
  --muted: #a9b6c4;
  --line: #2b3646;
  --red: #d71920;
  --red2: #ff4d55;
  --green: #29d17d;
  --green2: #9cffc7;
  --amber: #f5b84b;
  --blue: #77c8ff;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 19px;
  line-height: 1.65;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(215, 25, 32, .22), transparent 34rem),
    radial-gradient(circle at bottom right, rgba(41, 209, 125, .16), transparent 30rem),
    linear-gradient(180deg, #070a0e, var(--bg));
}

a { color: inherit; }
.nav {
  position: sticky;
  top: 10px;
  z-index: 10;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  max-width: 1180px;
  margin: 10px auto 26px;
  padding: 8px;
  border: 1px solid rgba(43, 54, 70, .75);
  border-radius: 999px;
  background: rgba(9, 13, 18, .82);
  backdrop-filter: blur(14px);
}
.nav a, .back {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(20, 27, 38, .72);
  color: var(--text);
  text-decoration: none;
  font-weight: 750;
  font-size: 14px;
}
.nav a:hover, .back:hover { border-color: var(--red2); color: #fff; }
.nav a.active { border-color: rgba(41, 209, 125, .55); color: #b8ffd8; background: rgba(41, 209, 125, .14); }
.hero {
  max-width: 1180px;
  margin: 0 auto;
  padding: 58px 22px 36px;
}
.hero.home {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(320px, .95fr);
  gap: 24px;
  align-items: stretch;
}
.hero.with-image { padding: 0 22px 36px; }
.hero-image {
  position: relative;
  min-height: 560px;
  overflow: hidden;
  border: 1px solid rgba(43, 54, 70, .75);
  border-radius: 30px;
  background: #05070a;
}
.hero-image img {
  display: block;
  width: 100%;
  height: 620px;
  object-fit: cover;
  filter: saturate(1.08) contrast(1.06);
}
.hero-image::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(6, 8, 11, .02) 0%, rgba(6, 8, 11, .18) 52%, rgba(6, 8, 11, .88) 100%);
}
.hero-content {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(300px, .75fr);
  gap: 22px;
  align-items: end;
  margin-top: -190px;
  padding: 0 30px 30px;
}
.hero-content.one-column {
  grid-template-columns: minmax(0, 760px);
}
.lesson-hero {
  padding-bottom: 28px;
}
.hero-card, .terminal-card, .node-map {
  border: 1px solid rgba(255, 255, 255, .1);
  border-radius: 26px;
  background: rgba(20, 27, 38, .92);
  box-shadow: 0 22px 70px rgba(0, 0, 0, .35);
}
.hero-card {
  padding: 34px;
  background:
    linear-gradient(135deg, rgba(215, 25, 32, .96), rgba(111, 12, 20, .92)),
    var(--card);
}
.with-image .hero-card, .with-image .node-map {
  border-color: rgba(43, 54, 70, .85);
  background: rgba(9, 13, 18, .80);
  backdrop-filter: blur(14px);
}
.terminal-card, .node-map { padding: 24px; }
.hero-logo {
  margin-bottom: 16px;
}
.hero-logo img {
  display: block;
  width: min(220px, 58vw);
  height: auto;
  filter: drop-shadow(0 12px 28px rgba(0, 0, 0, .32));
}
.kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
  color: var(--green2);
  font-size: 13px;
  font-weight: 950;
  letter-spacing: .11em;
  text-transform: uppercase;
}
h1, h2, h3 { line-height: 1.05; }
h1 {
  margin: 0 0 16px;
  max-width: 900px;
  font-size: clamp(42px, 7vw, 82px);
  letter-spacing: -.06em;
}
h2 {
  margin: 0 0 12px;
  font-size: clamp(27px, 3.3vw, 43px);
  letter-spacing: -.035em;
}
h3 {
  margin: 0 0 8px;
  font-size: 23px;
}
p { margin: 0 0 14px; color: #dce7f0; }
.lede {
  max-width: 790px;
  color: #f7fbff;
  font-size: clamp(20px, 2.3vw, 28px);
  line-height: 1.35;
}
.start-actions { margin-top: 24px; }
.badges { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 22px; }
.badge {
  display: inline-flex;
  padding: 8px 11px;
  border-radius: 999px;
  color: #071109;
  background: #fff;
  font-size: 14px;
  font-weight: 950;
}
.badge.green { background: var(--green); }
.badge.amber { background: var(--amber); }
.badge.red { background: #fff; color: var(--red); }
.section {
  max-width: 1180px;
  margin: 0 auto 22px;
  padding: 22px;
}
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 20px;
}
.grid.two-up { grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); }
.course-path {
  display: grid;
  gap: 14px;
}
.path-row {
  display: grid;
  grid-template-columns: 48px minmax(180px, .42fr) minmax(0, 1fr);
  gap: 16px;
  align-items: center;
  padding: 18px;
  border: 1px solid rgba(43, 54, 70, .75);
  border-radius: 20px;
  color: var(--text);
  background: rgba(20, 27, 38, .86);
  text-decoration: none;
}
.path-row:hover { border-color: rgba(41, 209, 125, .62); }
.path-row span {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 999px;
  color: #06110a;
  background: var(--green);
  font-weight: 950;
}
.path-row strong {
  font-size: clamp(21px, 2vw, 27px);
  line-height: 1.1;
}
.path-row em {
  color: #dce7f0;
  font-size: clamp(19px, 1.7vw, 22px);
  font-style: normal;
}
.path-row code {
  display: inline-block;
  padding: .08rem .42rem;
  border: 1px solid rgba(41, 209, 125, .48);
  border-radius: 999px;
  color: #dfffe9;
  background: rgba(41, 209, 125, .16);
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: .9em;
  font-weight: 850;
}
.command-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}
.command-list .card {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  padding: 18px;
}
.command-list .card h2,
.command-list .card p {
  margin: 0;
}
.command-list .card h2 {
  font-size: 1rem;
  line-height: 1;
  letter-spacing: 0;
}
.command-list .card h2 code {
  display: block;
  width: 100%;
  overflow-x: auto;
  white-space: nowrap;
  padding: 12px 14px;
  border: 1px solid rgba(41, 209, 125, .42);
  border-radius: 14px;
  color: #eafff0;
  background: #020503;
  box-shadow: inset 0 0 22px rgba(41, 209, 125, .08);
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: clamp(18px, 1.8vw, 22px);
  line-height: 1.35;
}
.command-list .card p {
  padding-left: 2px;
}
.card, .tile, .callout {
  display: block;
  padding: 24px;
  border: 1px solid rgba(255, 255, 255, .1);
  border-radius: 22px;
  background: rgba(20, 27, 38, .92);
  text-decoration: none;
}
.tile:hover { border-color: rgba(41, 209, 125, .65); transform: translateY(-1px); }
.tile p, li { font-size: 20px; }
.card p, .step p { font-size: clamp(21px, 2vw, 24px); }
.callout p { font-size: clamp(20px, 2vw, 23px); }
.number {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  margin-bottom: 12px;
  border-radius: 999px;
  background: var(--red);
  color: #fff;
  font-weight: 950;
}
.callout.green { border-color: rgba(41, 209, 125, .55); background: rgba(12, 56, 33, .72); }
.callout.red { border-color: rgba(255, 77, 85, .55); background: rgba(89, 13, 22, .72); }
.steps {
  display: grid;
  gap: 18px;
  counter-reset: step;
}
.step {
  position: relative;
  padding: 22px 22px 22px 70px;
  border: 1px solid rgba(255, 255, 255, .1);
  border-radius: 20px;
  background: rgba(16, 23, 34, .88);
}
.step::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 20px;
  top: 20px;
  width: 34px;
  height: 34px;
  border-radius: 999px;
  display: grid;
  place-items: center;
  background: var(--red);
  color: #fff;
  font-weight: 950;
}
/* inline-command-pill: validator marker for body-copy command pills */
.card p code,
.tile p code,
.callout p code,
.step p code,
li code,
.hero-card p code,
.node-map code,
.lede code {
  display: inline-block;
  padding: .08rem .42rem;
  border: 1px solid rgba(41, 209, 125, .48);
  border-radius: 999px;
  color: #dfffe9;
  background: rgba(41, 209, 125, .16);
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: .92em;
  font-weight: 850;
}
.terminal-guidance {
  margin: 0 0 12px;
  color: #b8ffd8;
  font-size: 20px;
  font-weight: 850;
}
.terminal {
  display: grid;
  gap: 8px;
  margin: 12px 0 0;
  padding: 16px;
  overflow-x: auto;
  border: 1px solid rgba(41, 209, 125, .42);
  border-radius: 16px;
  color: #dfffe9;
  background: #020503;
  box-shadow: inset 0 0 26px rgba(41, 209, 125, .08);
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: clamp(17px, 2vw, 21px);
  line-height: 1.55;
}
.terminal-line {
  display: grid;
  grid-template-columns: 138px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
}
.terminal-label {
  display: inline-flex;
  justify-content: center;
  padding: 4px 8px;
  border-radius: 999px;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 12px;
  font-weight: 950;
  letter-spacing: .08em;
  text-transform: uppercase;
  white-space: nowrap;
}
.terminal-label.type { background: rgba(41, 209, 125, .16); border: 1px solid rgba(41, 209, 125, .52); color: #b8ffd8; }
.terminal-label.output { background: rgba(169, 182, 196, .12); border: 1px solid rgba(169, 182, 196, .32); color: #dce7f0; }
.terminal-label.note { background: rgba(245, 184, 75, .14); border: 1px solid rgba(245, 184, 75, .46); color: #ffe1a6; }
.terminal code {
  display: block;
  color: #f5fff8;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}
.terminal-command { color: #f5fff8; }
.terminal-output { color: #dce7f0; }
.terminal-note { color: #ffe1a6; }
.node-map {
  display: grid;
  gap: 12px;
}
.map-row {
  display: grid;
  grid-template-columns: 110px 1fr;
  gap: 12px;
  align-items: center;
  padding: 13px;
  border: 1px solid rgba(255, 255, 255, .09);
  border-radius: 16px;
  background: rgba(0, 0, 0, .18);
}
.map-row span { font-size: 20px; }
.map-row strong { color: var(--green2); font-size: 20px; }
ul { margin-top: 0; }
.course-progress {
  max-width: 1180px;
  margin: 14px auto 0;
  padding: 0 22px 18px;
}
.course-progress h2 {
  margin: 0 0 10px;
  color: #b8ffd8;
  font-size: 15px;
  line-height: 1;
  letter-spacing: .08em;
  text-transform: uppercase;
}
.course-progress-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 10px;
  border: 1px solid rgba(43, 54, 70, .72);
  border-radius: 999px;
  background: rgba(9, 13, 18, .58);
}
.course-progress a {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 8px 10px;
  border: 1px solid rgba(43, 54, 70, .9);
  border-radius: 999px;
  color: #dce7f0;
  background: rgba(20, 27, 38, .72);
  text-decoration: none;
  font-size: 14px;
  font-weight: 850;
}
.course-progress a span {
  display: inline-grid;
  place-items: center;
  width: 22px;
  height: 22px;
  border-radius: 999px;
  color: #06110a;
  background: rgba(41, 209, 125, .85);
  font-size: 12px;
  font-weight: 950;
}
.course-progress a.active {
  border-color: rgba(41, 209, 125, .68);
  color: #b8ffd8;
  background: rgba(41, 209, 125, .14);
}
.course-progress a.reference {
  border-color: rgba(43, 54, 70, .9);
  color: #dce7f0;
}
.course-progress a.reference span {
  color: #06110a;
  background: rgba(41, 209, 125, .85);
}
.course-progress a.reference.active {
  border-color: rgba(41, 209, 125, .68);
  color: #b8ffd8;
  background: rgba(41, 209, 125, .14);
}
.next-prev {
  max-width: 1180px;
  margin: 0 auto 46px;
  padding: 18px 22px 0;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 12px;
  border-top: 1px solid rgba(43, 54, 70, .72);
}
.next-prev.single-next { justify-content: flex-end; }
.back {
  min-width: 190px;
  justify-content: center;
  padding: 12px 16px;
  border-color: rgba(41, 209, 125, .5);
  color: #dfffe9;
  font-size: 15px;
  font-weight: 900;
}
.back.next {
  margin-left: auto;
  border-color: rgba(41, 209, 125, .62);
  color: #b8ffd8;
  background: rgba(41, 209, 125, .12);
}
.back.prev {
  border-color: rgba(169, 182, 196, .32);
  color: #dce7f0;
}
footer {
  max-width: 1180px;
  margin: 20px auto 0;
  padding: 28px 22px 46px;
  color: var(--muted);
}
@media (max-width: 820px) {
  .hero.home, .hero-content, .path-row { grid-template-columns: 1fr; }
  .hero-content { margin-top: -120px; padding: 0 16px 22px; }
  .hero-image img { height: 520px; }
  .terminal-line { grid-template-columns: 1fr; }
}