/* Realsee's blue-and-white visual language, applied to this case study. */
:root {
  color-scheme: light;
  --paper: #ffffff;
  --surface: #f7faff;
  --ink: #061526;
  --muted: #33465c;
  --line: #e3eaf2;
  --accent: #0a73fe;
  --link: #0757c7;
  --wash: #ecf4ff;
  --header-height: 64px;
  --font: "Inter", "Geist Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --mono: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", monospace;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--header-height) + 24px); }
body { margin: 0; padding-top: var(--header-height); background: var(--paper); color: var(--ink); font-family: var(--font); font-size: 16px; line-height: 1.75; -webkit-font-smoothing: antialiased; }
::selection { background: #cde4ff; color: var(--ink); }
a { color: var(--link); text-underline-offset: .2em; text-decoration-thickness: 1px; }
a:hover { color: var(--accent); }
a:focus-visible { outline: 3px solid var(--accent); outline-offset: 5px; border-radius: 2px; }
img { display: block; max-width: 100%; height: auto; }
figure { margin: 0; }
h1, h2, h3, h4, p { margin-top: 0; }
h1, h2, h3, h4 { line-height: 1.25; text-wrap: balance; }
button, input { font: inherit; }
button { cursor: pointer; }
button:disabled { cursor: wait; opacity: .65; }
button:focus-visible, [tabindex]:focus-visible { outline: 3px solid var(--accent); outline-offset: 4px; }
[hidden] { display: none !important; }
.skip-link { position: fixed; top: .5rem; left: 1rem; z-index: 20; padding: .6rem 1rem; border-radius: 4px; background: var(--ink); color: white; transform: translateY(-180%); }
.skip-link:focus { transform: translateY(0); color: white; }
.header-inner, .home-main, .doc-shell, .site-footer { width: min(1200px, calc(100% - 64px)); margin-inline: auto; }
.site-header { position: fixed; inset: 0 0 auto; z-index: 10; height: var(--header-height); border-bottom: 1px solid var(--line); background: rgb(255 255 255 / 94%); backdrop-filter: blur(12px); }
.header-inner { display: flex; align-items: center; gap: 2rem; height: 100%; }
.brand { color: var(--ink); font-size: .95rem; font-weight: 700; letter-spacing: -.025em; text-decoration: none; line-height: 1.35; }
.brand:hover { color: var(--link); }
.header-nav { display: flex; flex-wrap: wrap; align-items: center; gap: 1.6rem; margin-left: auto; }
.header-nav a, .language-switch { color: var(--muted); font-size: .82rem; font-weight: 500; text-decoration: none; }
.header-nav a:hover, .header-nav a[aria-current="page"], .language-switch:hover { color: var(--link); }
.language-switch { flex-shrink: 0; padding-left: 1.5rem; border-left: 1px solid var(--line); }
.hero { padding: 100px 0 88px; text-align: center; }
.hero-copy { max-width: 1000px; margin-inline: auto; }
.eyebrow, .kicker { margin-bottom: 1.2rem; color: var(--link); font-family: var(--mono); font-size: 13px; font-weight: 500; letter-spacing: .06em; line-height: 1.5; text-transform: uppercase; }
.hero h1 { margin-bottom: 1.75rem; font-size: clamp(2.75rem, 5.6vw, 4.5rem); font-weight: 550; letter-spacing: -.055em; line-height: 1.09; }
.lead { max-width: 780px; margin: 0 auto 2rem; color: var(--muted); font-size: 20px; line-height: 1.7; text-wrap: pretty; }
.actions { display: flex; flex-wrap: wrap; gap: .75rem; align-items: center; }
.hero .actions { justify-content: center; }
.button { display: inline-flex; justify-content: center; align-items: center; min-height: 44px; padding: .7rem 1.25rem; border: 1px solid transparent; border-radius: 4px; background: var(--wash); color: var(--link); font-size: .875rem; font-weight: 600; text-decoration: none; line-height: 1.45; transition: background .15s ease, border-color .15s ease; }
.button:hover { background: #dcecff; color: var(--link); }
.button.secondary { border-color: var(--line); background: white; color: var(--muted); }
.button.secondary:hover { border-color: #a9c8ee; background: var(--surface); color: var(--link); }
.hero-visual { width: 100%; margin-top: 56px; }
.hero-visual img { width: 100%; border: 1px solid var(--line); border-radius: 4px; }
.hero-visual figcaption { padding-top: 14px; color: var(--muted); font-size: .75rem; line-height: 1.6; }
.tutorial-layout { display: grid; grid-template-columns: 235px minmax(0, 1fr); gap: 64px; align-items: start; }
.guide-nav { position: sticky; top: calc(var(--header-height) + 28px); font-size: .85rem; }
.guide-nav nav { display: grid; gap: 1rem; margin-bottom: 1.75rem; padding-right: 1.5rem; border-right: 1px solid var(--line); }
.guide-nav nav a { color: var(--muted); text-decoration: none; }
.guide-nav nav a:hover { color: var(--link); }
.tutorial-prose { max-width: 820px; }
.tour-embed, .walkthrough-video { display: block; width: 100%; aspect-ratio: 16 / 9; border: 1px solid var(--line); border-radius: 4px; background: #f2f6fb; }
.walkthrough-video { background: #061526; }
.media-section .section-heading { max-width: 920px; }
.model-viewer { position: relative; min-width: 0; height: 640px; height: clamp(400px, 60vw, 640px); overflow: hidden; border: 1px solid var(--line); border-radius: 4px; background: #f2f6fb; }
.model-canvas { width: 100%; height: 100%; }
.model-canvas canvas { display: block; width: 100%; height: 100%; touch-action: none; }
.model-cover { position: absolute; inset: 0; display: grid; justify-items: center; align-content: center; gap: 1.5rem; padding: 32px 24px 72px; background: #f2f6fb; }
.model-cover img { width: 75%; max-height: 400px; object-fit: contain; }
.model-cover .button { background: var(--accent); color: white; }
.model-status { position: absolute; right: 0; bottom: 0; left: 0; margin: 0; padding: 12px 18px; background: rgb(255 255 255 / 94%); color: var(--muted); font-size: .8rem; text-align: center; pointer-events: none; }
.model-tools { position: absolute; display: flex; flex-wrap: wrap; gap: 8px; top: 16px; left: 16px; right: 16px; }
.model-tools .button { min-height: 38px; background: white; border-color: var(--line); font-size: .8rem; padding: .45rem .8rem; }
.model-viewer:fullscreen { height: 100%; width: 100%; border: 0; }
.media-note { margin-top: 1rem; color: var(--muted); font-size: .85rem; }
.section { padding: 88px 0; border-top: 1px solid var(--line); }
.section-heading { max-width: 820px; margin-bottom: 3rem; }
.section-heading .eyebrow { margin-bottom: 1rem; }
.section h2, .preview h2 { margin-bottom: 1.4rem; font-size: clamp(2rem, 3.75vw, 3rem); font-weight: 500; letter-spacing: -.045em; line-height: 1.15; }
.section-heading > p:not(.eyebrow) { color: var(--muted); }
.steps { display: grid; }
.step { display: grid; grid-template-columns: 64px minmax(180px, .85fr) minmax(0, 1.15fr); gap: 2rem; align-items: start; min-width: 0; padding: 2rem 0; border-top: 1px solid var(--line); }
.step:last-child { padding-bottom: 0; }
.step-number { color: var(--accent); font-family: var(--mono); font-size: .82rem; font-variant-numeric: tabular-nums; }
.step h3 { margin-bottom: 0; font-size: 1.35rem; font-weight: 500; letter-spacing: -.025em; }
.step p { margin-bottom: 0; color: var(--muted); font-size: .97rem; }
.preview { display: grid; grid-template-columns: 1.1fr .9fr; gap: 5rem; align-items: center; padding: 88px 0; border-top: 1px solid var(--line); }
.preview > img, .preview > figure { width: 100%; min-width: 0; border: 1px solid var(--line); border-radius: 4px; }
.preview > div { min-width: 0; }
.preview p { color: var(--muted); font-size: 1rem; }
.preview .eyebrow { color: var(--link); font-size: 13px; }
.preview .actions { margin-top: 1.8rem; }
.resource-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 2rem; }
.resource { display: block; min-width: 0; padding: 1.7rem 0 0; border-top: 1px solid var(--line); color: var(--ink); text-decoration: none; transition: border-color .15s ease; }
.resource:hover { border-color: var(--accent); color: var(--link); }
.resource > span { display: block; margin-bottom: 1.4rem; }
.resource h3 { margin-bottom: .8rem; font-size: 1.3rem; font-weight: 500; letter-spacing: -.025em; }
.resource p { margin-bottom: 0; color: var(--muted); font-size: .93rem; }
.doc-shell { display: grid; grid-template-columns: 205px minmax(0, 820px); gap: clamp(2rem, 5vw, 5rem); justify-content: center; align-items: start; padding-block: 60px 96px; }
.sidebar { position: sticky; top: calc(var(--header-height) + 32px); min-width: 0; padding-right: 1.3rem; border-right: 1px solid var(--line); }
.sidebar .links { display: flex; flex-direction: column; gap: .3rem; }
.sidebar a { padding: .45rem .7rem; border-radius: 3px; color: var(--muted); font-size: .84rem; text-decoration: none; line-height: 1.6; }
.sidebar a:hover { background: var(--surface); color: var(--link); }
.sidebar a[aria-current="page"] { background: var(--wash); color: var(--link); font-weight: 550; }
.prose { min-width: 0; overflow-wrap: anywhere; }
.prose h1 { margin-bottom: 1.4rem; font-size: clamp(2rem, 3.5vw, 3rem); font-weight: 550; letter-spacing: -.045em; line-height: 1.2; }
.prose h2 { margin-top: 3rem; margin-bottom: 1.15rem; padding-top: 1.8rem; border-top: 1px solid var(--line); font-size: 1.8rem; font-weight: 550; letter-spacing: -.035em; }
.prose h3 { margin-top: 2rem; margin-bottom: .85rem; font-size: 1.25rem; font-weight: 550; }
.prose h4 { margin-top: 1.7rem; margin-bottom: .75rem; font-size: 1.05rem; }
.prose p, .prose ul, .prose ol { margin-bottom: 1.3rem; }
.prose li { margin-block: .4rem; }
.prose ul, .prose ol { padding-left: 1.45rem; }
.prose li > ul, .prose li > ol { margin-block: .5rem; }
.prose strong { font-weight: 650; }
.prose img { margin-block: 1.8rem; border: 1px solid var(--line); border-radius: 4px; }
.prose blockquote { margin: 1.6rem 0; padding: .9rem 1.3rem; border-left: 2px solid var(--accent); background: var(--surface); color: var(--muted); }
.prose blockquote p:last-child { margin-bottom: 0; }
code, pre { font-family: var(--mono); }
code { padding: .15em .35em; border-radius: 3px; background: #f0f5fb; font-size: .83em; }
.prose pre { max-width: 100%; margin-block: 1.6rem; padding: 1.3rem 1.5rem; overflow-x: auto; border: 1px solid var(--line); border-radius: 4px; background: var(--surface); font-size: .84rem; line-height: 1.8; overflow-wrap: normal; tab-size: 4; }
.prose pre code { padding: 0; border-radius: 0; background: transparent; font-size: inherit; }
.prose table { display: block; width: 100%; max-width: 100%; margin-block: 1.7rem; overflow-x: auto; border-collapse: collapse; font-size: .87rem; line-height: 1.7; }
.prose th, .prose td { min-width: 120px; padding: .85rem 1rem; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
.prose th { background: var(--surface); font-size: .8rem; font-weight: 650; }
.prose tbody tr:hover { background: var(--surface); }
.prose hr { margin-block: 2.4rem; border: 0; border-top: 1px solid var(--line); }
.site-footer { display: flex; flex-wrap: wrap; justify-content: space-between; gap: .8rem 2rem; padding-block: 28px 36px; border-top: 1px solid var(--line); color: var(--muted); font-size: .77rem; }
.site-footer p { margin-bottom: 0; }
.site-footer a { color: inherit; }
@media (max-width: 1000px) {
  .tutorial-layout { grid-template-columns: 195px minmax(0, 1fr); gap: 32px; }
  .header-inner { gap: 1.2rem; }
  .header-nav { gap: 1rem; }
  .hero { padding-block: 80px 64px; }
  .preview { gap: 2.5rem; }
  .doc-shell { grid-template-columns: 170px minmax(0, 1fr); gap: 2rem; }
  .step { grid-template-columns: 40px minmax(150px, .8fr) minmax(0, 1.2fr); gap: 1.5rem; }
}
@media (max-width: 760px) {
  :root { --header-height: 104px; }
  .header-inner, .home-main, .doc-shell, .site-footer { width: calc(100% - 40px); }
  .header-inner { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 4px 1rem; align-content: center; padding-block: 10px; }
  .brand { font-size: .92rem; }
  .language-switch { grid-column: 2; grid-row: 1; padding-left: .9rem; }
  .header-nav { grid-column: 1 / -1; grid-row: 2; margin: 0; gap: 1.2rem; flex-wrap: nowrap; min-width: 0; overflow-x: auto; }
  .header-nav a { display: inline-flex; align-items: center; min-height: 36px; flex-shrink: 0; }
  .tutorial-layout { grid-template-columns: minmax(0, 1fr); gap: 24px; }
  .guide-nav { position: static; }
  .guide-nav nav { border-right: 0; border-bottom: 1px solid var(--line); padding: 0 0 20px; }
  .tour-embed { aspect-ratio: 3 / 4; max-height: 640px; }
  .model-cover img { width: 100%; }
  .model-tools { left: 8px; top: 8px; right: 8px; gap: 5px; }
  .model-tools .button { font-size: .75rem; }
  .hero { padding-block: 60px 52px; }
  .hero h1 { font-size: clamp(2.35rem, 7vw, 3.3rem); letter-spacing: -.05em; }
  .lead { font-size: 1.08rem; }
  .hero-visual { margin-top: 36px; }
  .section, .preview { padding-block: 52px; }
  .section-heading { margin-bottom: 2rem; }
  .section h2, .preview h2 { font-size: 2rem; }
  .step { grid-template-columns: 30px minmax(0, 1fr); gap: .6rem 1rem; padding-block: 1.5rem; }
  .step-number { grid-row: 1 / 3; }
  .step h3 { font-size: 1.2rem; }
  .step p { grid-column: 2; }
  .preview { grid-template-columns: 1fr; gap: 2rem; }
  .resource-grid { grid-template-columns: 1fr; gap: 1.8rem; }
  .resource { padding-top: 1.3rem; }
  .resource > span { margin-bottom: .9rem; }
  .doc-shell { grid-template-columns: minmax(0, 1fr); gap: 2rem; padding-block: 24px 50px; }
  .sidebar { position: static; padding: 0 0 1rem; border-right: 0; border-bottom: 1px solid var(--line); }
  .sidebar .links { flex-direction: row; flex-wrap: wrap; gap: .2rem .45rem; }
  .sidebar a { padding: .35rem .6rem; }
  .prose h1 { font-size: 2rem; }
  .prose h2 { font-size: 1.5rem; }
  .prose pre { padding: 1rem; font-size: .78rem; }
  .prose th, .prose td { padding: .7rem .8rem; }
}
@media (max-width: 400px) {
  .header-inner, .home-main, .doc-shell, .site-footer { width: calc(100% - 32px); }
  .header-inner { gap: 3px .55rem; }
  .brand { font-size: .78rem; }
  .language-switch { padding-left: .55rem; font-size: .74rem; }
  .header-nav { gap: 1rem; }
  .header-nav a { font-size: .78rem; }
  .hero h1 { font-size: 2.15rem; }
  .hero .eyebrow { font-size: 11px; }
  .hero .actions { align-items: stretch; }
  .hero .button { flex: 1 1 100%; }
  .prose { font-size: .94rem; }
  .prose h1 { font-size: 1.8rem; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}
@media print {
  body { padding: 0; background: white; color: black; }
  .site-header, .sidebar, .site-footer, .skip-link { display: none; }
  .doc-shell { display: block; width: 100%; padding: 0; }
  .prose pre { white-space: pre-wrap; overflow-wrap: anywhere; }
  .prose table { display: table; font-size: .75rem; }
  .prose img { max-height: 22cm; object-fit: contain; break-inside: avoid; }
  a { color: inherit; }
}