/* How to Use - training page. Brand: IBEAN navy + blue. Light by default, follows OS dark mode. */
@font-face{font-family:"Plus Jakarta Sans";font-weight:400;font-display:swap;src:url(fonts/plus-jakarta-sans-latin-400-normal.woff2) format("woff2")}
@font-face{font-family:"Plus Jakarta Sans";font-weight:600;font-display:swap;src:url(fonts/plus-jakarta-sans-latin-600-normal.woff2) format("woff2")}
@font-face{font-family:"Plus Jakarta Sans";font-weight:700;font-display:swap;src:url(fonts/plus-jakarta-sans-latin-700-normal.woff2) format("woff2")}

:root{
  --navy:#071330;--navy-2:#0c183a;--blue:#1e3a82;--blue-2:#386cd1;--link:#1d4ed8;
  --bg:#f8fafc;--card:#fff;--text:#0f172a;--muted:#475569;--line:#e2e8f0;--soft:#eef3ff;
  --warn-bg:#fffbeb;--warn-line:#fcd34d;--warn-text:#78350f;--tip-bg:#eff6ff;--tip-line:#93c5fd;
  --kbd-bg:#f1f5f9;--code-bg:#f1f5f9;
}
@media (prefers-color-scheme:dark){
  :root{--bg:#040916;--card:#0a1530;--text:#e6ecfa;--muted:#a9b6d3;--line:#1b2c57;--soft:#10214c;--link:#8fb3ff;
    --warn-bg:#2a2108;--warn-line:#8a6d12;--warn-text:#fde9a8;--tip-bg:#0f1f45;--tip-line:#2b4a96;--kbd-bg:#14244d;--code-bg:#14244d}
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:84px}
body{margin:0;background:var(--bg);color:var(--text);font:400 17px/1.65 "Plus Jakarta Sans",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;-webkit-font-smoothing:antialiased}
a{color:var(--link)}
img{max-width:100%;height:auto;display:block}
kbd{font:600 .82em ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;background:var(--kbd-bg);border:1px solid var(--line);border-bottom-width:2px;border-radius:6px;padding:.08em .45em;white-space:nowrap}
code{font:500 .88em ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;background:var(--code-bg);border-radius:5px;padding:.1em .4em}
.skip{position:absolute;left:-999px;top:8px;background:#fff;color:#000;padding:8px 14px;border-radius:8px;z-index:100}
.skip:focus{left:8px}
:focus-visible{outline:3px solid var(--blue-2);outline-offset:2px;border-radius:4px}

/* top bar */
.top{position:sticky;top:0;z-index:50;background:var(--navy);color:#fff;border-bottom:1px solid #1a3678}
.top-in{max-width:1280px;margin:0 auto;padding:12px 20px;display:flex;align-items:center;gap:16px;flex-wrap:wrap}
.brand{font-weight:700;letter-spacing:.12em;color:#9db8ff;text-decoration:none;font-size:15px}
.brand b{color:#fff;letter-spacing:.02em;margin-left:10px;font-size:16px}
.top nav{display:flex;gap:18px;margin-left:auto;align-items:center;flex-wrap:wrap}
.top nav a{color:#dbe6ff;text-decoration:none;font-size:14px;font-weight:600}
.top nav a:hover{color:#fff}
.top nav a.btn{color:#fff;font-size:14px}
.btn{display:inline-flex;align-items:center;gap:8px;padding:10px 18px;border-radius:10px;font-weight:700;font-size:14px;text-decoration:none;border:1px solid transparent;cursor:pointer}
.btn-primary{background:var(--blue-2);color:#fff}
.btn-primary:hover{background:#4b7de0}
.btn-ghost{background:transparent;color:#fff;border-color:#3b5fb5}
.btn-ghost:hover{background:#12275a}

/* hero */
.hero{background:linear-gradient(135deg,#040916,#0c183a 60%,#10214c);color:#fff;padding:44px 20px 52px}
.hero-in{max-width:1280px;margin:0 auto;display:grid;grid-template-columns:minmax(0,1fr);gap:28px}
.eyebrow{font-size:13px;font-weight:700;letter-spacing:.14em;text-transform:uppercase;color:#9db8ff}
.hero h1{font-size:clamp(30px,4.4vw,52px);line-height:1.12;margin:8px 0 12px;letter-spacing:-.02em}
.hero p.lead{font-size:clamp(17px,1.6vw,20px);color:#c7d6f5;max-width:70ch;margin:0}
.badges{display:flex;gap:10px;flex-wrap:wrap;margin-top:18px}
.badge{padding:6px 14px;border-radius:999px;background:rgba(122,162,255,.14);border:1px solid rgba(122,162,255,.4);font-size:13px;font-weight:600}
.video-wrap{display:grid;grid-template-columns:minmax(0,2fr) minmax(260px,1fr);gap:20px;align-items:start}
.video-box{background:#000;border-radius:14px;overflow:hidden;box-shadow:0 18px 50px rgba(0,0,0,.5);border:1px solid #1a3678}
.video-box video{width:100%;aspect-ratio:16/9;display:block;background:#000}
.chapter-list{background:rgba(255,255,255,.06);border:1px solid #1a3678;border-radius:14px;padding:14px;max-height:520px;overflow:auto}
.chapter-list h2{font-size:15px;margin:2px 6px 8px;color:#dbe6ff}
.chapter-list ol{list-style:none;margin:0;padding:0}
.chapter-list button{all:unset;display:flex;gap:10px;align-items:baseline;width:100%;box-sizing:border-box;padding:8px 10px;border-radius:8px;cursor:pointer;color:#e6ecfa;font-size:14px;line-height:1.35}
.chapter-list button:hover,.chapter-list button:focus-visible{background:#12275a}
.chapter-list .t{margin-left:auto;font:600 12px ui-monospace,Consolas,monospace;color:#9db8ff;flex:none}
.chapter-list .n{flex:none;width:22px;height:22px;border-radius:50%;background:var(--blue-2);color:#fff;font:700 12px/22px system-ui;text-align:center}

/* layout */
.layout{max-width:1280px;margin:0 auto;padding:32px 20px 60px;display:grid;grid-template-columns:260px minmax(0,1fr);gap:40px}
.toc{position:sticky;top:84px;align-self:start;max-height:calc(100vh - 100px);overflow:auto;font-size:14px}
.toc h2{font-size:12px;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);margin:0 0 10px}
.toc ol{list-style:none;margin:0 0 18px;padding:0}
.toc a{display:flex;gap:10px;padding:6px 10px;border-radius:8px;text-decoration:none;color:var(--text);line-height:1.35}
.toc a:hover{background:var(--soft)}
.toc a.active{background:var(--soft);color:var(--link);font-weight:700}
.toc .n{flex:none;width:22px;color:var(--muted);font-weight:700}
main{min-width:0;max-width:980px}
.block{background:var(--card);border:1px solid var(--line);border-radius:16px;padding:28px;margin:0 0 28px}
.block>h2,.chapter h2{font-size:clamp(24px,2.6vw,32px);line-height:1.2;margin:0 0 6px;letter-spacing:-.01em}
.lead2{color:var(--muted);margin:0 0 18px}

/* quick start */
.qs{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin:18px 0 0;padding:0;list-style:none}
.qs li{background:var(--soft);border:1px solid var(--line);border-radius:14px;padding:16px}
.qs .n{display:inline-grid;place-items:center;width:30px;height:30px;border-radius:50%;background:var(--blue-2);color:#fff;font-weight:700;margin-bottom:8px}
.qs h3{font-size:16px;margin:0 0 6px}
.qs p{margin:0;font-size:14.5px;color:var(--muted);line-height:1.5}

/* chapters */
.chapter{background:var(--card);border:1px solid var(--line);border-radius:16px;padding:28px;margin:0 0 28px}
.ch-head{display:flex;gap:16px;align-items:flex-start;margin-bottom:12px}
.ch-num{flex:none;display:grid;place-items:center;width:46px;height:46px;border-radius:14px;background:var(--blue);color:#fff;font:700 20px system-ui}
.ch-head>div{flex:1;min-width:0}
.summary{margin:0;color:var(--muted);font-weight:600}
.seek{all:unset;cursor:pointer;flex:none;font-size:13px;font-weight:700;color:var(--link);border:1px solid var(--line);border-radius:999px;padding:7px 14px;white-space:nowrap}
.seek:hover,.seek:focus-visible{background:var(--soft)}
.intro{margin:14px 0}
.steps{counter-reset:s;list-style:none;margin:16px 0;padding:0}
.steps li{counter-increment:s;position:relative;padding:4px 0 12px 44px}
.steps li::before{content:counter(s);position:absolute;left:0;top:2px;width:28px;height:28px;border-radius:50%;background:var(--soft);border:1px solid var(--tip-line);color:var(--link);font:700 14px/26px system-ui;text-align:center}
.steps.legend li::before{display:none}
.steps.legend li{padding-left:0}
.shot{margin:20px 0}
.shot .zoom{all:unset;display:block;cursor:zoom-in;border:1px solid var(--line);border-radius:12px;overflow:hidden;box-shadow:0 8px 28px rgba(15,23,42,.12);width:100%}
.shot .zoom:focus-visible{outline:3px solid var(--blue-2)}
.shot figcaption{font-size:14px;color:var(--muted);margin-top:8px;text-align:center}
.callout{border-radius:12px;padding:14px 18px;margin:16px 0;border:1px solid var(--tip-line);background:var(--tip-bg)}
.callout h3{margin:0 0 6px;font-size:14px;letter-spacing:.04em;text-transform:uppercase;color:var(--link)}
.callout ul{margin:0;padding-left:20px}
.callout li{margin:4px 0}
.table-wrap{overflow-x:auto;margin:16px 0;border:1px solid var(--line);border-radius:12px}
table{border-collapse:collapse;width:100%;font-size:15px}
th,td{padding:10px 14px;text-align:left;border-bottom:1px solid var(--line);vertical-align:top}
th{background:var(--soft);font-size:13px;letter-spacing:.04em;text-transform:uppercase;color:var(--muted)}
tr:last-child td{border-bottom:0}
.bp{margin:0;padding-left:22px}.bp li{margin:8px 0}
.faq details{border:1px solid var(--line);border-radius:12px;margin:10px 0;background:var(--card)}
.faq summary{cursor:pointer;padding:14px 18px;font-weight:700;list-style:none;display:flex;justify-content:space-between;gap:12px}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";color:var(--link);font-weight:700;font-size:20px;line-height:1}
.faq details[open] summary::after{content:"\2212"}
.faq details p{margin:0;padding:0 18px 16px;color:var(--muted)}
.cta{text-align:center;background:linear-gradient(135deg,#071330,#12307a);color:#fff;border-radius:16px;padding:36px 24px;margin:0 0 28px}
.cta h2{margin:0 0 8px;font-size:30px}.cta p{margin:0 0 18px;color:#c7d6f5}
footer.site{background:var(--navy);color:#b9c8ee;font-size:14px;padding:26px 20px}
footer.site .in{max-width:1280px;margin:0 auto;display:flex;gap:18px;flex-wrap:wrap;justify-content:space-between}
footer.site a{color:#dbe6ff}

/* lightbox */
dialog#lightbox{border:0;padding:0;background:transparent;max-width:96vw;max-height:96vh;overflow:visible}
dialog#lightbox::backdrop{background:rgba(2,6,23,.82)}
dialog#lightbox img{max-width:96vw;max-height:92vh;border-radius:10px;background:#fff}
dialog#lightbox button{position:absolute;top:-14px;right:-14px;width:40px;height:40px;border-radius:50%;border:0;background:#fff;color:#000;font-size:22px;cursor:pointer;box-shadow:0 4px 14px rgba(0,0,0,.4)}

@media (max-width:1020px){
  .layout{grid-template-columns:1fr}
  .toc{display:none}
  .video-wrap{grid-template-columns:1fr}
  .chapter-list{max-height:320px}
  .qs{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:560px){
  .qs{grid-template-columns:1fr}
  .block,.chapter{padding:18px}
  .ch-head{flex-wrap:wrap}.seek{order:3}
  .top nav a.hide-sm{display:none}
}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}}

/* print / PDF */
@media print{
  :root{--bg:#fff;--card:#fff;--text:#111;--muted:#444;--line:#cfd6e4;--soft:#f1f5ff;--link:#1d4ed8}
  body{font-size:11.5pt;background:#fff}
  .top,.toc,.video-wrap,.seek,.cta,.hero .badges,.no-print{display:none!important}
  .hero{background:#fff;color:#000;padding:0 0 14px;border-bottom:2px solid #1e3a82}
  .hero p.lead{color:#333}.eyebrow{color:#1e3a82}
  .layout{display:block;padding:0}
  .block,.chapter{border:0;border-radius:0;padding:0;margin:0 0 18pt;box-shadow:none}
  .chapter{break-before:page}
  #quick-start{break-before:avoid}
  .shot{break-inside:avoid}.shot .zoom{box-shadow:none}
  .callout,.table-wrap,.qs li{break-inside:avoid}
  .faq details{break-inside:avoid}.faq details>p{display:block}
  a{color:#1d4ed8;text-decoration:none}
  footer.site{background:#fff;color:#444;border-top:1px solid #ccc}footer.site a{color:#1d4ed8}
}