:root{
  --navy:#19242D; --ink:#0B1621; --blue:#185BAF; --blue-dk:#12498F; --blue-lt:#F1F6FC; --blue-md:#C9DBF2;
  --orange:#CE632B; --orange-lt:#FFF3EA; --green:#2E7D4F; --green-lt:#EAF6EF; --amber:#B7791F; --amber-lt:#FFF7E3;
  --red:#B83A3A; --red-lt:#FCEDED; --muted:#5A6672; --line:#E1E7EE; --bg:#FFFFFF; --soft:#F7F9FC;
  --radius:14px; --max:1120px;
  --font:"DM Sans",Arial,Helvetica,sans-serif; --mono:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:76px}
body{margin:0;background:var(--bg);color:var(--navy);font-family:var(--font);font-size:17px;line-height:1.6;-webkit-font-smoothing:antialiased}
img{max-width:100%;height:auto;display:block}
a{color:var(--blue)}
a:hover{color:var(--blue-dk)}
h1,h2,h3,h4{line-height:1.2;margin:0 0 .5em;color:var(--navy);letter-spacing:-.01em}
h1{font-size:clamp(2.2rem,5vw,3.6rem);font-weight:800}
h2{font-size:clamp(1.6rem,3.2vw,2.3rem);font-weight:800}
h3{font-size:1.2rem;font-weight:700}
p{margin:0 0 1em}
.wrap{max-width:var(--max);margin:0 auto;padding:0 20px}
.eyebrow{font-size:.78rem;font-weight:700;letter-spacing:.14em;text-transform:uppercase;color:var(--orange);margin-bottom:.6em}
.lede{font-size:1.18rem;color:var(--muted);max-width:760px}
.muted{color:var(--muted)}
.hl{color:var(--blue)}
.hl-o{color:var(--orange)}
.small{font-size:.88rem}
.source{font-size:.8rem;color:var(--muted);margin-top:14px}
.source a{color:var(--muted)}

/* Header */
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.94);backdrop-filter:saturate(1.4) blur(8px);border-bottom:1px solid var(--line)}
.site-header .wrap{display:flex;align-items:center;justify-content:space-between;gap:16px;height:64px}
.brand img{height:30px;width:auto}
.nav{display:flex;gap:4px;align-items:center}
.nav a{text-decoration:none;color:var(--navy);font-weight:600;font-size:.92rem;padding:8px 12px;border-radius:8px}
.nav a:hover,.nav a[aria-current=page]{background:var(--blue-lt);color:var(--blue)}
.nav .btn{margin-left:6px}
.menu-btn{display:none;background:none;border:1px solid var(--line);border-radius:8px;padding:8px 10px;font:inherit;font-weight:700;color:var(--navy);cursor:pointer}
@media (max-width:880px){
  .menu-btn{display:block}
  .nav{display:none;position:absolute;top:64px;left:0;right:0;background:#fff;border-bottom:1px solid var(--line);flex-direction:column;align-items:stretch;padding:10px 16px 16px}
  .nav.open{display:flex}
  .nav .btn{margin:6px 0 0;text-align:center}
}

/* Buttons */
.btn{display:inline-flex;align-items:center;gap:8px;background:var(--blue);color:#fff !important;text-decoration:none;font-weight:700;padding:12px 18px;border-radius:10px;border:0;font:inherit;font-weight:700;cursor:pointer;font-size:.95rem}
.btn:hover{background:var(--blue-dk)}
.btn.orange{background:var(--orange)}
.btn.orange:hover{background:#B4541F}
.btn.ghost{background:#fff;color:var(--navy) !important;border:1.5px solid var(--line)}
.btn.ghost:hover{border-color:var(--blue);color:var(--blue) !important}
.btn.sm{padding:8px 12px;font-size:.85rem}
.btn-row{display:flex;flex-wrap:wrap;gap:10px;margin-top:22px}

/* Hero */
.hero{padding:72px 0 56px;background:linear-gradient(180deg,var(--blue-lt),#fff 85%);position:relative;overflow:hidden}
.hero h1 .sub{display:block;font-size:.52em;font-weight:700;color:var(--blue);margin-top:.35em}
.hero .meta{color:var(--muted);font-weight:600;margin-top:10px}
.spark{position:absolute;right:6%;top:40px;width:120px;opacity:.9}
@media (max-width:700px){.spark{display:none}}

/* Sections */
section{padding:64px 0;border-top:1px solid var(--line)}
section.alt{background:var(--soft)}
.sec-head{margin-bottom:28px;max-width:820px}
.part{display:inline-flex;align-items:center;gap:10px;font-weight:800;color:var(--blue);font-size:.85rem;letter-spacing:.08em;text-transform:uppercase;margin-bottom:10px}
.part b{display:inline-grid;place-items:center;width:28px;height:28px;border-radius:8px;background:var(--blue);color:#fff;font-size:.85rem;letter-spacing:0}

/* Grid and cards */
.grid{display:grid;gap:18px}
.g2{grid-template-columns:repeat(2,minmax(0,1fr))}
.g3{grid-template-columns:repeat(3,minmax(0,1fr))}
.g4{grid-template-columns:repeat(4,minmax(0,1fr))}
@media (max-width:900px){.g3,.g4{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media (max-width:640px){.g2,.g3,.g4{grid-template-columns:1fr}}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px}
.card.blue{background:var(--blue-lt);border-color:var(--blue-md)}
.card.dark{background:var(--blue-dk);color:#fff;border-color:var(--blue-dk)}
.card.dark h3,.card.dark h4{color:#fff}
.card.navy{background:var(--navy);color:#fff;border-color:var(--navy)}
.card.navy h3{color:#fff}
.card.orange{background:var(--orange-lt);border-color:#F3D3BD}
.card h3{margin-bottom:.35em}
.card p:last-child,.card ul:last-child{margin-bottom:0}
.tag{display:inline-block;font-size:.72rem;font-weight:800;letter-spacing:.1em;text-transform:uppercase;padding:3px 8px;border-radius:6px;background:var(--blue-lt);color:var(--blue);margin-bottom:10px}
.tag.o{background:var(--orange-lt);color:var(--orange)}
.tag.g{background:var(--green-lt);color:var(--green)}
.tag.a{background:var(--amber-lt);color:var(--amber)}
.tag.r{background:var(--red-lt);color:var(--red)}
ul.clean{list-style:none;padding:0;margin:0}
ul.clean li{padding:6px 0 6px 26px;position:relative}
ul.clean li::before{content:"";position:absolute;left:4px;top:15px;width:10px;height:10px;border-radius:3px;background:var(--blue)}
ul.x li::before{background:none;content:"\2715";color:var(--muted);top:6px;width:auto;height:auto;font-size:.85rem}
ul.check li::before{background:none;content:"\2713";color:var(--blue);top:5px;width:auto;height:auto;font-weight:800}
.big{font-size:clamp(2.4rem,5vw,3.4rem);font-weight:800;line-height:1;color:var(--blue);margin-bottom:8px}
.big.o{color:var(--orange)}
.quote{font-size:1.35rem;font-weight:700;line-height:1.35;color:var(--navy);border-left:5px solid var(--orange);padding:4px 0 4px 18px;margin:0 0 12px}
.quote cite{display:block;font-size:.9rem;font-style:normal;color:var(--blue);margin-top:10px;font-weight:700}
.callout{background:var(--navy);color:#fff;border-radius:var(--radius);padding:22px 26px;font-weight:700;font-size:1.12rem}
.callout .hl-o{color:#FFB688}
.arrow{display:grid;place-items:center;color:var(--orange);font-size:2rem;font-weight:800}

/* AI OS diagram */
.os{border:3px solid var(--orange);border-radius:18px;padding:34px 20px 20px;position:relative;background:#fff}
.os-label{position:absolute;top:-13px;left:20px;background:#fff;padding:0 10px;color:var(--orange);font-weight:800;letter-spacing:.14em;font-size:.8rem}
.os-row{display:grid;grid-template-columns:1fr auto 1fr auto 1fr;gap:12px;align-items:stretch}
.os-box{border-radius:12px;padding:18px;color:#fff}
.os-box h4{color:#fff;margin:0 0 6px;font-size:1.05rem;letter-spacing:.06em;text-transform:uppercase}
.os-box p{margin:0;font-size:.95rem;opacity:.95}
.os-box.c{background:#5B8FD6}.os-box.w{background:var(--blue)}.os-box.a{background:var(--blue-dk)}
.os-row .arrow{font-size:1.6rem}
@media (max-width:700px){.os-row{grid-template-columns:1fr}.os-row .arrow{transform:rotate(90deg)}}

/* Data tiers */
.tier{border-radius:var(--radius);padding:22px;border:1px solid}
.tier.g{background:var(--green-lt);border-color:#BFE3CD}
.tier.a{background:var(--amber-lt);border-color:#F1DBA5}
.tier.r{background:var(--red-lt);border-color:#F0C4C4}
.tier h3{font-size:1.5rem;margin-bottom:.2em}
.tier .k{font-weight:800;letter-spacing:.12em;font-size:.78rem}
.tier.g .k,.tier.g h3{color:var(--green)}.tier.a .k,.tier.a h3{color:var(--amber)}.tier.r .k,.tier.r h3{color:var(--red)}
.tier .rule{border-top:1px solid rgba(0,0,0,.1);margin-top:12px;padding-top:12px;font-weight:600;font-size:.95rem}
.dot{display:inline-block;width:11px;height:11px;border-radius:50%;vertical-align:middle;margin-right:6px}
.dot.g{background:var(--green)}.dot.a{background:#E0A526}.dot.r{background:var(--red)}

/* Charts */
.chart{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px}
.chart h4{margin:0 0 4px;font-size:1rem}
.chart .sub{font-size:.85rem;color:var(--muted);margin-bottom:16px}
.bars{display:grid;gap:8px}
.bar{display:grid;grid-template-columns:minmax(110px,38%) 1fr;gap:10px;align-items:center;font-size:.9rem}
.bar .lbl{text-align:right;color:var(--navy)}
.bar .track{background:var(--soft);border-radius:6px;height:24px;position:relative}
.bar .fill{height:100%;border-radius:6px;background:var(--orange);display:flex;align-items:center;justify-content:flex-end;padding-right:8px;color:#fff;font-weight:800;font-size:.8rem;min-width:34px}
.bar .fill.blue{background:var(--blue)}
.bar .fill.navy{background:var(--navy)}
.bar .fill.lt{background:#5B9BE6}
.legend{display:flex;gap:16px;flex-wrap:wrap;font-size:.82rem;color:var(--muted);margin-bottom:12px}
.legend span::before{content:"";display:inline-block;width:12px;height:12px;border-radius:3px;margin-right:6px;vertical-align:-1px;background:var(--c)}
.vbars{display:flex;align-items:flex-end;gap:6px;height:220px;padding-top:10px;border-bottom:1px solid var(--line)}
.vbar{flex:1;display:flex;flex-direction:column;justify-content:flex-end;align-items:center;min-width:0;height:100%}
.vbar .col{width:100%;border-radius:5px 5px 0 0;display:flex;justify-content:center;color:#fff;font-weight:800;font-size:.75rem;padding-top:4px}
.vlabels{display:flex;gap:6px;margin-top:6px}
.vlabels span{flex:1;font-size:.68rem;color:var(--muted);text-align:center;line-height:1.2;min-width:0;overflow-wrap:anywhere}
@media (max-width:640px){.vlabels span{font-size:.55rem}.vbar .col{font-size:.6rem}}
.horizon{display:grid;gap:14px}
.horizon .row{display:grid;grid-template-columns:70px 1fr;gap:12px;align-items:center}
.horizon .yr{font-weight:800;color:var(--muted)}
.horizon .yr.now{color:var(--blue)}
.horizon .b{height:40px;border-radius:8px;display:flex;align-items:center;padding:0 14px;font-weight:700}
.ladder-steps{display:grid;gap:6px;margin-top:18px}
.ladder-steps div{display:grid;grid-template-columns:86px 1fr;gap:10px;font-size:.88rem;padding:6px 10px;border-radius:8px;background:var(--soft)}
.ladder-steps b{color:var(--blue)}

/* Road map */
.road{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:10px;counter-reset:r}
.road a{display:block;text-decoration:none;color:var(--navy);background:#fff;border:1px solid var(--line);border-radius:12px;padding:16px;transition:.15s}
.road a:hover{border-color:var(--blue);transform:translateY(-2px)}
.road .k{font-size:.72rem;font-weight:800;letter-spacing:.12em;color:var(--orange)}
.road h4{margin:.3em 0 .2em;font-size:1rem}
.road p{margin:0;font-size:.85rem;color:var(--muted)}
@media (max-width:900px){.road{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media (max-width:480px){.road{grid-template-columns:1fr}}

/* Model ladder */
.mladder{display:grid;gap:10px}
.mladder div{display:grid;grid-template-columns:44px 220px 1fr;gap:12px;align-items:center;padding:14px 16px;border-radius:12px}
.mladder .n{font-weight:800;font-size:1.1rem}
.mladder div:nth-child(1){background:var(--blue-lt)}
.mladder div:nth-child(2){background:var(--blue-md)}
.mladder div:nth-child(3){background:var(--blue);color:#fff}
.mladder div:nth-child(4){background:var(--blue-dk);color:#fff}
@media (max-width:640px){.mladder div{grid-template-columns:36px 1fr}.mladder div span:last-child{grid-column:2}}

/* Code / skill file */
pre.skill{background:var(--navy);color:#E6EDF5;border-radius:var(--radius);padding:20px;overflow:auto;font-family:var(--mono);font-size:.84rem;line-height:1.55;margin:0;white-space:pre-wrap}
pre.skill .c{color:#FFB688}
pre.skill .f{color:#8FB8F0}

/* Tables */
.table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:var(--radius);background:#fff}
table{border-collapse:collapse;width:100%;font-size:.93rem}
th,td{text-align:left;padding:12px 14px;border-bottom:1px solid var(--line);vertical-align:top}
th{background:var(--blue-lt);color:var(--blue-dk);font-size:.8rem;letter-spacing:.06em;text-transform:uppercase}
tr:last-child td{border-bottom:0}

/* Steps */
.steps{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px}
.step{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:20px;border-top:5px solid var(--blue)}
.step .n{font-weight:800;color:var(--orange);font-size:1.4rem}
@media (max-width:900px){.steps{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media (max-width:520px){.steps{grid-template-columns:1fr}}

/* FAQ */
details.faq{background:#fff;border:1px solid var(--line);border-radius:12px;padding:0 18px;margin-bottom:10px}
details.faq summary{cursor:pointer;font-weight:700;padding:16px 28px 16px 0;list-style:none;position:relative}
details.faq summary::-webkit-details-marker{display:none}
details.faq summary::after{content:"+";position:absolute;right:0;top:12px;font-size:1.4rem;color:var(--blue)}
details.faq[open] summary::after{content:"\2212"}
details.faq .ans{padding:0 0 16px;color:var(--navy)}
.faq-group{margin-bottom:28px}
.faq-group h3{color:var(--blue);margin-bottom:12px}

/* References */
.refs{columns:2;column-gap:36px;font-size:.92rem}
.refs li{break-inside:avoid;margin-bottom:10px}
@media (max-width:760px){.refs{columns:1}}

/* Downloads */
.dl{display:flex;gap:14px;align-items:flex-start;background:#fff;border:1px solid var(--line);border-radius:12px;padding:16px;text-decoration:none;color:var(--navy)}
.dl:hover{border-color:var(--blue)}
.dl .ic{flex:none;width:42px;height:42px;border-radius:10px;background:var(--blue-lt);color:var(--blue);display:grid;place-items:center;font-weight:800;font-size:.7rem;letter-spacing:.04em}
.dl .ic.o{background:var(--orange-lt);color:var(--orange)}
.dl h4{margin:0 0 2px;font-size:1rem}
.dl p{margin:0;font-size:.86rem;color:var(--muted)}

/* Glossary */
dl.gloss{display:grid;grid-template-columns:200px 1fr;gap:10px 22px;margin:0}
dl.gloss dt{font-weight:800;color:var(--blue-dk)}
dl.gloss dd{margin:0}
@media (max-width:640px){dl.gloss{grid-template-columns:1fr}dl.gloss dd{margin-bottom:10px}}

/* Footer */
.site-footer{background:var(--navy);color:#C9D3DE;padding:44px 0;font-size:.92rem}
.site-footer a{color:#fff}
.site-footer .wrap{display:flex;flex-wrap:wrap;gap:24px;justify-content:space-between;align-items:center}
.site-footer .links{display:flex;gap:18px;flex-wrap:wrap}

/* Screens */
.shot{border:1px solid var(--line);border-radius:12px;overflow:hidden;box-shadow:0 12px 30px rgba(18,73,143,.10);background:#fff}
.shot .bar-top{height:28px;background:#EEF2F7;display:flex;gap:6px;align-items:center;padding:0 12px}
.shot .bar-top i{width:10px;height:10px;border-radius:50%;background:#CBD5E1;display:block}

/* About */
.about{display:grid;grid-template-columns:180px 1fr;gap:28px;align-items:center}
.about img{border-radius:16px;width:180px}
@media (max-width:640px){.about{grid-template-columns:1fr}.about img{width:140px}}

/* Plan page */
.plan-section{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:24px;margin-bottom:18px}
.plan-section h2{font-size:1.35rem;display:flex;gap:10px;align-items:center}
.plan-section h2 .n{display:inline-grid;place-items:center;width:32px;height:32px;border-radius:9px;background:var(--blue);color:#fff;font-size:1rem}
.plan-section .hint{color:var(--muted);font-size:.92rem;margin-bottom:14px}
label.f{display:block;font-weight:700;font-size:.9rem;margin:12px 0 6px}
input[type=text],input[type=date],input[type=number],textarea,select{width:100%;font:inherit;font-size:.95rem;padding:10px 12px;border:1.5px solid var(--line);border-radius:9px;background:#fff;color:var(--navy)}
input:focus,textarea:focus,select:focus{outline:none;border-color:var(--blue);box-shadow:0 0 0 3px rgba(24,91,175,.15)}
textarea{min-height:84px;resize:vertical}
.chk{display:flex;gap:10px;align-items:flex-start;padding:8px 0}
.chk input{margin-top:5px;width:18px;height:18px;accent-color:var(--blue);flex:none}
.plan-table input,.plan-table select{padding:7px 9px;font-size:.9rem}
.plan-table td{padding:8px}
.plan-toolbar{position:sticky;top:64px;z-index:20;background:rgba(255,255,255,.96);border-bottom:1px solid var(--line);padding:10px 0;margin-bottom:20px}
.plan-toolbar .wrap{display:flex;gap:10px;flex-wrap:wrap;align-items:center}
.save-note{font-size:.85rem;color:var(--muted);margin-left:auto}
.calc{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}
@media (max-width:700px){.calc{grid-template-columns:1fr 1fr}}
.calc-out{font-size:1.8rem;font-weight:800;color:var(--blue)}

@media print{
  .site-header,.site-footer,.plan-toolbar,.no-print,.btn{display:none !important}
  body{font-size:11pt}
  section{padding:16px 0;border:0}
  .plan-section{break-inside:avoid;border:1px solid #ccc}
  input,textarea,select{border:1px solid #bbb}
  a{color:var(--navy);text-decoration:none}
}

/* Collapse custom inline grids on small screens */
@media (max-width:760px){
  .grid[style*="grid-template-columns"]:not(#habits){grid-template-columns:1fr !important}
  .grid > .arrow{transform:rotate(90deg);padding:2px 0}
  .bar{grid-template-columns:minmax(90px,40%) 1fr;font-size:.82rem}
}