:root {
  color-scheme: dark;
  --bg: #071318;
  --bg-soft: #0a1a20;
  --panel: #0d2027;
  --panel-2: #112a32;
  --line: #203b44;
  --text: #edf5f5;
  --muted: #9db2b8;
  --teal: #54d9ca;
  --teal-soft: rgba(84, 217, 202, .1);
  --orange: #ffb15a;
  --orange-soft: rgba(255, 177, 90, .1);
  --sidebar: 18.5rem;
  --content: 67rem;
  --radius: 1rem;
  --shadow: 0 1.5rem 4rem rgba(0, 0, 0, .24);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 1.5rem; }
body {
  margin: 0;
  background:
    radial-gradient(circle at 82% -5%, rgba(84, 217, 202, .11), transparent 30rem),
    radial-gradient(circle at 32% 42%, rgba(255, 177, 90, .035), transparent 38rem),
    var(--bg);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.72;
}
body.nav-open, body.lightbox-open { overflow: hidden; }
a { color: var(--teal); text-underline-offset: .2em; }
a:hover { color: #9cf3ea; }
img, video { max-width: 100%; }
button, input { font: inherit; }
code, .eyebrow, .kicker, .section-number, .side-nav p, .feature-card > span, .example > span, .hero-note > span {
  font-family: "Cascadia Code", "SFMono-Regular", Consolas, monospace;
}
code { border: 1px solid rgba(84, 217, 202, .2); border-radius: .3rem; background: var(--teal-soft); color: #d2fff9; padding: .08rem .28rem; font-size: .9em; }

.reading-progress { position: fixed; inset: 0 auto auto 0; z-index: 90; width: 0; height: 3px; background: linear-gradient(90deg, var(--teal), var(--orange)); }
.sidebar { position: fixed; inset: 0 auto 0 0; z-index: 40; width: var(--sidebar); overflow-y: auto; border-right: 1px solid var(--line); background: rgba(7, 19, 24, .95); padding: 1.4rem 1rem 2rem; backdrop-filter: blur(14px); scrollbar-width: thin; scrollbar-color: var(--line) transparent; }
.language-switch { display: block; margin: 0 0 1rem; }
.language-switch span { display: block; margin: 0 0 .35rem .1rem; color: var(--muted); font: 700 .64rem "Cascadia Code", Consolas, monospace; letter-spacing: .08em; text-transform: uppercase; }
.language-switch select { width: 100%; min-height: 2.35rem; border: 1px solid var(--line); border-radius: .5rem; outline: none; background: var(--panel); color: var(--text); padding: .35rem .5rem; cursor: pointer; }
.language-switch select:focus { border-color: var(--teal); box-shadow: 0 0 0 2px var(--teal-soft); }
.download-mini { display: block; margin-bottom: 1.2rem; border: 1px solid rgba(84,217,202,.28); border-radius: .75rem; background: var(--teal-soft); padding: .7rem .8rem; color: var(--text); text-decoration: none; }
.download-mini span, .download-mini strong { display: block; }
.download-mini span { color: var(--muted); font-size: .68rem; text-transform: uppercase; letter-spacing: .08em; }
.download-mini strong { margin-top: .18rem; color: var(--teal); font-size: .78rem; }
.side-nav p { margin: 1.15rem .65rem .35rem; color: var(--orange); font-size: .64rem; letter-spacing: .1em; text-transform: uppercase; }
.side-nav a { display: block; border-left: 2px solid transparent; border-radius: 0 .35rem .35rem 0; color: var(--muted); padding: .27rem .65rem; text-decoration: none; font-size: .83rem; line-height: 1.4; }
.nav-badge { display: inline-block; margin-left: .42rem; border: 1px solid rgba(84,217,202,.45); border-radius: .3rem; background: var(--teal-soft); color: var(--teal); padding: .08rem .28rem; font: 700 .58rem/1.2 "Cascadia Code", Consolas, monospace; letter-spacing: .05em; vertical-align: .08em; }
.side-nav a:hover, .side-nav a.active { border-left-color: var(--teal); background: var(--teal-soft); color: var(--text); }
.mobile-header { display: none; }

.main { margin-left: var(--sidebar); }
.content { width: min(100% - 3rem, var(--content)); margin: 0 auto; padding: 0 0 5rem; }
.hero { display: flex; flex-direction: column; justify-content: center; padding: 5rem 0 4rem; border-bottom: 1px solid var(--line); }
.eyebrow, .kicker { margin: 0 0 .65rem; color: var(--teal); font-size: .72rem; font-weight: 700; letter-spacing: .13em; text-transform: uppercase; }
.hero h1 { max-width: none; margin: 0; font-size: clamp(2.15rem, 7.3vw, 5.8rem); line-height: 1.04; letter-spacing: -.015em; }
.hero-line { display: block; width: max-content; max-width: 100%; white-space: nowrap; }
.hero-accent { color: var(--teal); }
.hero-lead { max-width: 48rem; margin: 1.8rem 0 0; color: #bed0d4; font-size: clamp(1.05rem, 2vw, 1.3rem); }
.hero-actions { display: flex; flex-wrap: wrap; gap: .75rem; margin-top: 1.7rem; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 2.8rem; border: 1px solid var(--teal); border-radius: .6rem; padding: .58rem 1rem; text-decoration: none; font-weight: 750; transition: transform .18s ease, background .18s ease; }
.button:hover { transform: translateY(-2px); }
.button.primary { background: var(--teal); color: #061014; }
.button.primary:hover { background: #8af0e5; color: #061014; }
.button.ghost { background: transparent; color: var(--teal); }
.hero-note { display: flex; align-items: center; gap: .8rem; max-width: 47rem; margin-top: 2rem; border-left: 2px solid var(--orange); background: var(--orange-soft); padding: .7rem .9rem; }
.hero-note span { border: 1px solid rgba(255,177,90,.35); border-radius: 999px; color: var(--orange); padding: .1rem .45rem; font-size: .65rem; }
.hero-note p { margin: 0; color: #d7e0e1; font-size: .9rem; }

.doc-section { padding: 5rem 0; border-bottom: 1px solid var(--line); }
.intro-section { padding-top: 6rem; }
.section-heading { display: grid; grid-template-columns: 3.5rem minmax(0, 1fr); gap: 1.1rem; align-items: start; margin-bottom: 1.3rem; }
.section-heading.compact { grid-template-columns: 3rem minmax(0, 1fr); }
.section-number { color: var(--orange); font-size: .75rem; padding-top: .32rem; }
h2, h3 { line-height: 1.2; letter-spacing: -.025em; }
.section-heading h2, .chapter-heading h2 { margin: 0; font-size: clamp(2rem, 4.7vw, 3.25rem); }
.section-heading.compact h2 { font-size: clamp(1.8rem, 4vw, 2.75rem); }
h3 { margin: 1.5rem 0 .55rem; font-size: 1.25rem; }
p { margin: .65rem 0 1rem; }
.section-lead { max-width: 54rem; color: #bed0d4; font-size: 1.1rem; }
.muted { color: var(--muted); }
.chapter-heading { padding: 6rem 0 2.6rem; }
.chapter-heading span { display: inline-block; border: 1px solid rgba(84,217,202,.28); border-radius: 999px; background: var(--teal-soft); color: var(--teal); padding: .18rem .58rem; font-size: .7rem; font-weight: 800; letter-spacing: .08em; text-transform: uppercase; }
.chapter-heading.accent span { border-color: rgba(255,177,90,.34); background: var(--orange-soft); color: var(--orange); }
.chapter-heading.future span { border-color: rgba(157,117,255,.4); background: rgba(157,117,255,.1); color: #bca2ff; }
.chapter-heading h2 { max-width: 16ch; margin-top: .75rem; }

.feature-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1rem; margin-top: 1.6rem; }
.feature-grid.two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.feature-card, .mini-card { border: 1px solid var(--line); border-radius: var(--radius); background: linear-gradient(145deg, rgba(17,42,50,.86), rgba(9,25,31,.9)); padding: 1.2rem 1.25rem; }
.feature-card > span { color: var(--orange); font-size: .66rem; letter-spacing: .08em; text-transform: uppercase; }
.feature-card h3, .mini-card h3 { margin-top: .65rem; }
.feature-card p:last-child, .mini-card p:last-child { margin-bottom: 0; }
.split-content { display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(16rem, .8fr); gap: 1.3rem; align-items: start; }
.mini-card { margin-top: .4rem; }
.accent-card { border-color: rgba(255,177,90,.3); background: var(--orange-soft); }
.example { margin: 1.2rem 0; border-left: 3px solid var(--orange); background: var(--orange-soft); padding: .85rem 1rem; }
.example > span { color: var(--orange); font-size: .66rem; font-weight: 800; letter-spacing: .1em; text-transform: uppercase; }
.example p { margin: .35rem 0 0; }
.callout { margin: 1.5rem 0 0; border-left: 3px solid var(--teal); background: var(--teal-soft); padding: .85rem 1rem; }
.callout.warning { border-left-color: var(--orange); background: var(--orange-soft); }
.callout strong { color: var(--text); }

.install-panel { display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.2fr); gap: 2rem; border: 1px solid var(--line); border-radius: 1.2rem; background: linear-gradient(140deg, rgba(84,217,202,.08), rgba(17,42,50,.7)); padding: 1.5rem; box-shadow: var(--shadow); }
.install-panel h3 { margin-top: 0; }
.install-panel .button { word-break: break-word; text-align: center; }
.install-steps { display: grid; gap: .85rem; margin: 0; padding: 0; list-style: none; }
.install-steps li { display: grid; grid-template-columns: 2rem 1fr; gap: .75rem; }
.install-steps li > span { display: grid; place-items: center; width: 2rem; height: 2rem; border-radius: 50%; background: var(--teal); color: #061014; font-weight: 900; }
.install-steps strong { display: block; }
.install-steps p { margin: .15rem 0 0; color: var(--muted); font-size: .9rem; }

.media-grid { display: grid; gap: 1rem; margin: 1.6rem 0; }
.media-grid.two-images { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.media-grid.single-media { max-width: 56rem; }
.media-card, .video-card { margin: 0; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; background: #050c0f; box-shadow: var(--shadow); }
.media-open { position: relative; display: block; width: 100%; border: 0; background: #050c0f; padding: 0; color: var(--text); cursor: zoom-in; }
.media-open img { display: block; width: 100%; height: auto; transition: opacity .18s ease; }
.media-open:hover img { opacity: .82; }
.media-open > span { position: absolute; right: .7rem; bottom: .7rem; border: 1px solid rgba(255,255,255,.2); border-radius: .4rem; background: rgba(5,12,15,.82); padding: .25rem .5rem; font-size: .7rem; }
.media-card figcaption, .video-card figcaption { border-top: 1px solid var(--line); background: var(--panel); padding: .8rem 1rem; }
.media-card figcaption strong, .video-card figcaption strong { display: block; }
.media-card figcaption p, .video-card figcaption p { margin: .18rem 0 0; color: var(--muted); font-size: .86rem; }
.media-feature { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(18rem, .75fr); gap: 1.5rem; align-items: start; }
.media-feature.reverse { grid-template-columns: minmax(0, 1.08fr) minmax(20rem, .92fr); }
.media-feature.reverse figure { order: 2; }
.info-columns { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; margin-top: 1.2rem; }
.info-columns article { border-top: 2px solid var(--teal); background: rgba(13,32,39,.52); padding: 0 1rem 1rem; }
.info-columns article:nth-child(even) { border-color: var(--orange); }
.info-columns h3 { margin-top: 1rem; }
ul { padding-left: 1.2rem; }
li { margin: .45rem 0; }
.check-list { display: grid; gap: .45rem; padding: 0; list-style: none; }
.check-list li { position: relative; margin: 0; padding-left: 1.65rem; }
.check-list li::before { content: "✓"; position: absolute; left: 0; color: var(--teal); font-weight: 900; }
.flow-row { display: grid; grid-template-columns: repeat(5, auto); gap: .7rem; align-items: center; margin: 1.5rem 0; }
.flow-row div { display: flex; align-items: center; gap: .6rem; border: 1px solid var(--line); border-radius: .7rem; background: var(--panel); padding: .7rem .85rem; }
.flow-row div span { color: var(--orange); font-weight: 900; }
.flow-row i { color: var(--teal); font-style: normal; }

.control-cards { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; }
.control-cards article { border: 1px solid var(--line); border-radius: var(--radius); background: var(--panel); padding: 1.2rem; }
.control-cards h3 { margin: .5rem 0; }
.control-cards p { margin-bottom: 0; color: var(--muted); }
.big-value { color: var(--teal); font-size: clamp(1.7rem, 4vw, 2.5rem); font-weight: 900; letter-spacing: -.04em; }
.video-card { margin: 1.6rem 0; }
.video-card video { display: block; width: 100%; max-height: 68vh; background: #000; }
.video-card figcaption { display: flex; justify-content: space-between; gap: 1rem; align-items: center; }
.watch-button { flex: 0 0 auto; border: 1px solid var(--teal); border-radius: .45rem; background: transparent; color: var(--teal); padding: .36rem .65rem; cursor: pointer; }
.watch-button:hover { background: var(--teal-soft); }
.video-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; margin-top: 1.5rem; }
.video-grid .video-card { margin: 0; }
.video-card.compact video { aspect-ratio: 16 / 9; object-fit: contain; }
.tool-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: .8rem; margin-top: 1.4rem; }
.tool-grid article { border: 1px solid var(--line); border-radius: .75rem; background: rgba(13,32,39,.65); padding: .9rem 1rem; }
.tool-grid b { color: var(--orange); }
.tool-grid p { margin: .3rem 0 0; color: var(--muted); font-size: .9rem; }
.change-list { display: grid; gap: .7rem; padding: 0; list-style: none; }
.change-list li { border-left: 2px solid var(--teal); background: var(--teal-soft); margin: 0; padding: .7rem .9rem; }
.roadmap-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; margin-top: 1.5rem; }
.roadmap-grid article { position: relative; overflow: hidden; min-height: 11rem; border: 1px solid rgba(157,117,255,.28); border-radius: var(--radius); background: linear-gradient(145deg, rgba(157,117,255,.1), rgba(13,32,39,.82)); padding: 1.2rem; }
.roadmap-grid article > span { color: #bca2ff; font: 700 .7rem "Cascadia Code", Consolas, monospace; }
.roadmap-grid h3 { margin: .65rem 0 .45rem; }
.roadmap-grid p { margin: 0; color: var(--muted); }

.closing-card { margin: 6rem 0 2rem; border: 1px solid rgba(84,217,202,.3); border-radius: 1.2rem; background: radial-gradient(circle at 90% 0, rgba(84,217,202,.16), transparent 23rem), var(--panel); padding: clamp(1.5rem, 5vw, 3rem); text-align: center; box-shadow: var(--shadow); }
.closing-card h2 { margin: 0; font-size: clamp(2rem, 5vw, 3.5rem); }
.closing-card p:not(.kicker) { max-width: 40rem; margin: .8rem auto 1.4rem; color: var(--muted); }
.footer { display: flex; justify-content: space-between; gap: 1rem; border-top: 1px solid var(--line); color: var(--muted); padding: 2rem 0; font-size: .82rem; }
.footer p { margin: 0; }

.lightbox { position: fixed; inset: 0; z-index: 120; display: grid; grid-template-columns: 3.25rem minmax(0, 1fr) 3.25rem; align-items: center; gap: .8rem; background: rgba(2, 7, 9, .94); padding: 3.8rem 1rem 1.2rem; }
.lightbox[hidden] { display: none; }
.lightbox-stage { min-width: 0; text-align: center; }
.lightbox-stage img, .lightbox-stage video { display: none; max-width: min(100%, 88rem); max-height: 80vh; margin: auto; border: 1px solid var(--line); border-radius: .65rem; background: #000; }
.lightbox-stage .visible { display: block; }
.lightbox-stage p { margin: .7rem 0 0; color: #c8d7d9; }
.lightbox-close, .lightbox-nav { border: 1px solid var(--line); background: var(--panel); color: var(--text); cursor: pointer; }
.lightbox-close:hover, .lightbox-nav:hover { border-color: var(--teal); color: var(--teal); }
.lightbox-close { position: fixed; inset-block-start: max(1rem, env(safe-area-inset-top)); inset-inline-end: max(1rem, env(safe-area-inset-right)); z-index: 4; display: grid; place-items: center; width: 2.65rem; height: 2.65rem; border-radius: 50%; padding: 0; font-size: 1.55rem; line-height: 1; }
.lightbox-nav { width: 3rem; height: 4rem; border-radius: .55rem; font-size: 2.3rem; line-height: 1; }

@media (max-width: 980px) {
  .feature-grid { grid-template-columns: 1fr; }
  .feature-grid.two, .media-grid.two-images, .info-columns, .control-cards, .video-grid { grid-template-columns: 1fr; }
  .media-feature, .media-feature.reverse { grid-template-columns: 1fr; }
  .media-feature.reverse figure { order: 0; }
  .tool-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .roadmap-grid { grid-template-columns: 1fr; }
  .flow-row { grid-template-columns: 1fr; }
  .flow-row i { transform: rotate(90deg); text-align: center; }
}

@media (max-width: 780px) {
  html { scroll-padding-top: 4.5rem; }
  .mobile-header { position: fixed; inset: 0 0 auto 0; z-index: 60; display: flex; height: 3.6rem; align-items: center; justify-content: space-between; border-bottom: 1px solid var(--line); background: rgba(7,19,24,.94); padding: 0 .85rem; backdrop-filter: blur(14px); }
  .mobile-brand { color: var(--teal); text-decoration: none; font-weight: 900; letter-spacing: .04em; }
  .menu-button { border: 1px solid var(--line); border-radius: .45rem; background: var(--panel); color: var(--text); padding: .32rem .65rem; }
  .sidebar { width: min(88vw, 21rem); transform: translateX(-100%); padding-top: 4.5rem; transition: transform .2s ease; }
  body.nav-open .sidebar { transform: translateX(0); box-shadow: 1.2rem 0 3rem rgba(0,0,0,.45); }
  .main { margin-left: 0; }
  .content { width: min(100% - 2rem, var(--content)); }
  .hero { min-height: 86vh; padding-top: 7rem; }
  .hero h1 { font-size: clamp(2.15rem, 9.4vw, 4.25rem); }
  .doc-section { padding: 4rem 0; }
  .section-heading, .section-heading.compact { grid-template-columns: 2.2rem minmax(0, 1fr); gap: .55rem; }
  .split-content, .install-panel { grid-template-columns: 1fr; }
  .tool-grid { grid-template-columns: 1fr; }
  .video-card figcaption { align-items: flex-start; flex-direction: column; }
  .footer { flex-direction: column; }
  .lightbox { grid-template-columns: 2.5rem minmax(0, 1fr) 2.5rem; padding-inline: .35rem; gap: .25rem; }
  .lightbox-nav { width: 2.3rem; height: 3.2rem; }
}

@media (max-width: 480px) {
  .hero h1 { font-size: 8.2vw; }
  .hero-actions .button, .install-panel .button { width: 100%; }
  .hero-note { align-items: flex-start; flex-direction: column; }
  .section-heading h2, .section-heading.compact h2 { font-size: 1.85rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; }
}

@media print {
  :root { color-scheme: light; --bg: #fff; --panel: #fff; --panel-2: #fff; --line: #ccc; --text: #111; --muted: #555; }
  body { background: #fff; }
  .sidebar, .mobile-header, .reading-progress, .hero-actions, .watch-button, .lightbox { display: none !important; }
  .main { margin: 0; }
  .content { width: 100%; max-width: none; }
  .hero { min-height: auto; }
  .doc-section { break-inside: avoid; }
}