/* ═══════════════════════════════════════════════════════════════════════
   HW Designs — shared site stylesheet (assets/site.css)
   Used by: /index.html (hub) · /esp32-s3/index.html · /esp32-s3/dvt/
   Theme: "circuit copper & cobalt" — ink-navy dark surfaces, cobalt
   primary, copper secondary. No green (the boards supply that).
   Every text/background pair verified ≥ 4.5:1 (most ≥ 6:1) WCAG AA.
   Colors and fonts live in :root below — edit once, applies site-wide.
   ═══════════════════════════════════════════════════════════════════════ */
:root{
  color-scheme: light;
  /* Light surfaces */
  --paper:#F6F7FB;         /* page background                  */
  --card:#FFFFFF;          /* cards & tables                   */
  --tint:#EDF1FA;          /* alternating section bands        */
  --ink:#12162E;           /* headings & body text  (16.6:1)   */
  --soft:#3F4966;          /* secondary text        (8.3:1)    */
  --label:#4E5878;         /* small labels          (6.6:1)    */
  --line:#DFE4F0;          /* borders                          */
  /* Dark surfaces */
  --navy:#0B1226;          /* hero & dark panels               */
  --navy-2:#151F42;        /* raised dark panels               */
  --bright:#F2F5FC;        /* text on navy          (17:1)     */
  --dim:#BAC4DE;           /* secondary on navy     (10.7:1)   */
  --faint:#8E9AC0;         /* tertiary on navy      (6.7:1)    */
  /* Accents */
  --cobalt:#1A4FD6;        /* primary — links, buttons, active (6.3:1 on paper) */
  --cobalt-ink:#1443B8;    /* primary text on cobalt-tint      */
  --cobalt-lt:#8FB1FF;     /* primary on navy       (8.8:1)    */
  --cobalt-tint:#E3EAFD;
  --copper:#C06A14;        /* secondary — decorative           */
  --copper-ink:#8F4E12;    /* secondary text        (6.0:1)    */
  --copper-lt:#F0A65A;     /* secondary on navy     (9.1:1)    */
  --copper-tint:#FBEEDD;
  --red-ink:#A8271F;       /* failures              (6.1:1)    */
  --red-tint:#FBE7E6;
  --gray-tint:#EDEFF5;
  --radius:10px;
  --sans:'Archivo',system-ui,-apple-system,'Segoe UI',sans-serif;
  --mono:'Spline Sans Mono',ui-monospace,'SF Mono',Menlo,Consolas,monospace;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:var(--sans);font-size:16.5px;line-height:1.6;color:var(--ink);background:var(--paper)}
::selection{background:var(--navy);color:#fff}
:focus-visible{outline:2px solid var(--cobalt);outline-offset:2px;border-radius:4px}
.wrap{max-width:1060px;margin:0 auto;padding:0 24px}
a{color:var(--cobalt)}

.skip{position:absolute;left:-999px;top:0;background:var(--navy);color:#fff;padding:10px 16px;z-index:99}
.skip:focus{left:12px;top:12px}

/* ── Header & pill-tab nav ─────────────────────────────────────────── */
.site-header{position:sticky;top:0;z-index:20;background:rgba(255,255,255,.94);backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
.header-inner{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:11px 24px;max-width:1060px;margin:0 auto}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none}
.logo{height:30px;width:auto;display:block}
.brand-fallback{font-weight:700;letter-spacing:.06em;color:var(--ink)}
.brand-docs{font-family:var(--mono);font-size:12px;color:var(--label);border:1px solid var(--line);border-radius:6px;padding:2px 7px}
.site-nav{display:flex;flex-wrap:wrap;gap:4px}
.site-nav a{font-size:14px;font-weight:500;color:var(--soft);text-decoration:none;padding:7px 12px;border-radius:999px;border:1px solid transparent;transition:background .15s ease,color .15s ease}
.site-nav a:hover{color:var(--cobalt-ink);background:var(--cobalt-tint)}
.site-nav a.active{color:var(--cobalt-ink);background:var(--cobalt-tint);border-color:#CBD8F8;font-weight:600}

/* ── Hero (ink-navy with faint circuit dot-grid) ───────────────────── */
.hero{background:var(--navy) radial-gradient(circle at 1px 1px,rgba(143,177,255,.13) 1px,transparent 1.6px);background-size:auto,26px 26px;color:var(--bright);padding:64px 0 60px}
.hero-grid{display:grid;grid-template-columns:1fr 250px;gap:52px;align-items:center}
.eyebrow{font-family:var(--mono);font-size:12px;letter-spacing:.18em;text-transform:uppercase;color:var(--copper-lt);margin:0;display:flex;align-items:center;gap:9px}
.rgb-dot{width:9px;height:9px;border-radius:50%;background:#6FE08A;animation:ledcycle 6s ease-in-out infinite;flex:none}
@keyframes ledcycle{0%,100%{background:#FF6A5A}33%{background:#6FE08A}66%{background:#6FB2FF}}
.hero h1{font-size:clamp(38px,6vw,62px);line-height:1.04;letter-spacing:-.015em;font-weight:700;margin:16px 0 16px;color:#fff;max-width:16ch}
.lede{font-size:clamp(17px,2vw,19.5px);color:var(--dim);max-width:58ch;margin:0 0 26px}
.cta-row{display:flex;flex-wrap:wrap;gap:12px;margin:0 0 18px}
.btn{display:inline-block;padding:12px 22px;border-radius:8px;font-weight:600;font-size:15.5px;text-decoration:none;border:1px solid transparent}
.btn-light{background:var(--cobalt);color:#fff}
.btn-light:hover{background:#1443B8}
.btn-ghost{border-color:rgba(186,196,222,.5);color:var(--bright)}
.btn-ghost:hover{border-color:var(--bright)}
.quickfacts{font-family:var(--mono);font-size:13px;color:var(--faint);margin:0}

/* Product shot: white card floating on navy with cobalt + copper glow.
   (Board renders now have white backgrounds, so the frame is light.)   */
.hero-shot{position:relative;margin:0;justify-self:center;background:#fff;border-radius:16px;padding:16px 12px;box-shadow:0 24px 70px rgba(4,8,20,.55)}
.hero-shot::before{content:"";position:absolute;inset:-18%;z-index:-1;background:radial-gradient(closest-side at 35% 40%,rgba(90,134,255,.4),transparent 70%),radial-gradient(closest-side at 70% 75%,rgba(240,166,90,.22),transparent 72%);pointer-events:none}
.hero-shot img{position:relative;display:block;height:440px;width:auto;max-width:100%}

/* ── Sections ──────────────────────────────────────────────────────── */
.section{padding:72px 0}
main > .section:nth-child(even){background:var(--tint)}
section{scroll-margin-top:96px}
.kicker{font-family:var(--mono);font-size:12px;letter-spacing:.18em;text-transform:uppercase;color:var(--copper-ink);margin:0}
.section h2{font-size:clamp(26px,3.4vw,34px);letter-spacing:-.01em;margin:10px 0 10px}
.section-intro{color:var(--soft);max-width:62ch;margin:0}

/* ── Getting-started steps ─────────────────────────────────────────── */
.steps{list-style:none;margin:36px 0 0;padding:0;display:grid;gap:14px}
.step{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:24px 26px;display:grid;grid-template-columns:44px 1fr;gap:20px}
.step-no{font-family:var(--mono);font-size:16px;color:#fff;background:var(--cobalt);width:40px;height:40px;border-radius:8px;display:grid;place-items:center}
.step h3{margin:7px 0 8px;font-size:19px}
.step p{margin:0 0 10px;color:var(--soft)}
.step p:last-child{margin-bottom:0}
pre{background:#F0F2F8;color:#181D36;border:1px solid var(--line);border-left:3px solid var(--cobalt);border-radius:8px;padding:14px 18px;overflow-x:auto;font-family:var(--mono);font-size:13.5px;line-height:1.6;margin:12px 0}
code{font-family:var(--mono)}
p code,li code,td code{background:#E7EAF4;border-radius:5px;padding:2px 6px;font-size:.88em}
.settings{border-collapse:collapse;margin:12px 0 4px;font-size:14.5px}
.settings th,.settings td{text-align:left;padding:8px 22px 8px 0;border-bottom:1px solid var(--line)}
.settings th{font-weight:600;color:var(--ink)}
.settings td{font-family:var(--mono);font-size:13.5px;color:var(--soft)}
.hint{font-size:14px;color:var(--label)}

/* ── Board tour ────────────────────────────────────────────────────── */
.tour-grid{display:grid;grid-template-columns:1fr 1fr;gap:22px;margin:36px 0 0}
.tour-col h3{margin:0 0 12px;font-size:19px}
.render-frame{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:20px;display:flex;justify-content:center}
.render-frame img{display:block;height:520px;width:auto;max-width:100%}
.feat{list-style:none;margin:18px 0 0;padding:0;display:grid;gap:9px}
.feat li{position:relative;padding-left:20px;color:var(--soft);font-size:15.5px}
.feat li::before{content:"";position:absolute;left:0;top:9px;width:8px;height:8px;background:var(--copper)}
.notes{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin:30px 0 0}
.note{background:var(--card);border:1px solid var(--line);border-top:3px solid var(--copper);border-radius:var(--radius);padding:20px 22px}
.note h4{margin:0 0 8px;font-size:16px}
.note p{margin:0;color:var(--soft);font-size:14.5px}
.dims{font-family:var(--mono);font-size:13.5px;color:var(--label);margin:26px 0 0}
.diagram-frame{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:20px 20px 16px;margin:26px 0 0}
.diagram-frame > a{display:block}
.diagram-frame img{display:block;width:100%;height:auto}
.diagram-caption{font-size:14px;color:var(--label);margin:12px 2px 0;line-height:1.55}
.diagram-caption b{color:var(--soft)}

/* ── Spec grid ─────────────────────────────────────────────────────── */
.grid-specs{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin:36px 0 0}
.spec{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:18px 20px}
.spec .label{font-family:var(--mono);font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:var(--copper-ink)}
.spec .val{margin-top:8px;font-weight:600;font-size:15px;line-height:1.5}

/* ── Downloads table ───────────────────────────────────────────────── */
.dl-table{width:100%;border-collapse:collapse;margin:32px 0 0;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden}
.dl-table thead th{font-family:var(--mono);font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:var(--label);text-align:left;padding:14px 20px;border-bottom:1px solid var(--line);font-weight:500;background:var(--card)}
.dl-table td{padding:16px 20px;border-bottom:1px solid var(--line);vertical-align:top;background:var(--card)}
.dl-table tbody tr:last-child td{border-bottom:none}
.dl-table tbody tr:hover td{background:#F3F6FD}
.dl-name{font-weight:600}
.dl-desc{color:var(--soft);font-size:15px}
.dl-file a{font-family:var(--mono);font-size:13.5px;text-underline-offset:3px}
.table-note{font-size:14px;color:var(--label);margin:14px 0 0}

/* ── Example cards ─────────────────────────────────────────────────── */
.grid-ex{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin:36px 0 0}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:24px;display:flex;flex-direction:column;gap:10px}
.card h3{margin:0;font-size:18px}
.card p{margin:0;color:var(--soft);font-size:15px;flex:1}
.btn-sm{align-self:flex-start;font-size:14px;font-weight:600;color:var(--cobalt-ink);border:1.5px solid var(--cobalt);border-radius:7px;padding:8px 14px;text-decoration:none}
.btn-sm:hover{background:var(--cobalt);border-color:var(--cobalt);color:#fff}

/* ── Support ───────────────────────────────────────────────────────── */
.grid-support{display:grid;grid-template-columns:1fr 1.3fr;gap:14px;margin:36px 0 0}
.contact{background:var(--navy-2);color:var(--bright);border-radius:var(--radius);padding:26px 28px}
.contact h3{margin:0 0 8px;font-size:19px;color:#fff}
.contact p{margin:0 0 14px;color:var(--dim);font-size:15px}
.contact p:last-child{margin:0}
.contact a{color:var(--cobalt-lt);font-family:var(--mono);font-size:15px}
.faq{display:grid;gap:10px;align-content:start}
details{background:var(--card);border:1px solid var(--line);border-radius:var(--radius)}
summary{list-style:none;cursor:pointer;padding:16px 20px;font-weight:600;display:flex;justify-content:space-between;gap:12px}
summary::-webkit-details-marker{display:none}
summary::after{content:"+";font-family:var(--mono);color:var(--copper-ink)}
details[open] summary::after{content:"–"}
details p{margin:0;padding:0 20px 16px;color:var(--soft);font-size:15px}

/* ── Hub board cards ───────────────────────────────────────────────── */
.grid-boards{display:grid;gap:16px}
.board-card{display:grid;grid-template-columns:200px 1fr;gap:26px;align-items:center;background:var(--card);border:1px solid var(--line);border-radius:14px;padding:22px;text-decoration:none;transition:border-color .15s ease,box-shadow .15s ease}
.board-card:hover{border-color:var(--cobalt);box-shadow:0 8px 28px rgba(26,79,214,.12)}
.thumb{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:14px 10px;display:flex;justify-content:center}
.thumb img{display:block;height:230px;width:auto;max-width:100%}
.b-name{display:block;font-size:21px;font-weight:700;color:var(--ink);margin:0 0 6px}
.b-desc{display:block;color:var(--soft);font-size:15.5px;margin:0 0 12px}
.b-tags{display:block;font-family:var(--mono);font-size:12.5px;color:var(--copper-ink);margin:0 0 14px}
.b-go{display:inline-block;font-weight:600;font-size:15px;color:var(--cobalt)}
.board-card:hover .b-go{text-decoration:underline;text-underline-offset:4px}
.more-note{font-size:14.5px;color:var(--label);margin:20px 0 0}

/* ── Status pills & progress (DVT report) ──────────────────────────── */
.pill{display:inline-block;font-family:var(--mono);font-size:11.5px;letter-spacing:.06em;font-weight:500;border-radius:999px;padding:3px 10px;border:1px solid transparent;white-space:nowrap}
.pill-pass{background:var(--cobalt-tint);color:var(--cobalt-ink);border-color:#C9D7FA}
.pill-fail{background:var(--red-tint);color:var(--red-ink);border-color:#F2CBC8}
.pill-open{background:var(--copper-tint);color:var(--copper-ink);border-color:#F0D9BC}
.pill-na{background:var(--gray-tint);color:var(--label);border-color:#DCE0EC}
.progress{height:10px;border-radius:999px;background:var(--gray-tint);overflow:hidden;border:1px solid var(--line)}
.progress > span{display:block;height:100%;background:linear-gradient(90deg,var(--cobalt),#5A86FF)}

/* ── Footer ────────────────────────────────────────────────────────── */
.site-footer{border-top:1px solid var(--line);padding:26px 0 42px;background:var(--paper)}
.footer-inner{display:flex;flex-wrap:wrap;justify-content:space-between;gap:10px;font-size:14px;color:var(--label)}
.site-footer a{color:var(--label)}

/* ── Responsive ────────────────────────────────────────────────────── */
@media (max-width:900px){
  .hero-grid{grid-template-columns:1fr;gap:36px}
  .hero-shot{justify-self:start}
  .hero-shot img{height:380px}
  .tour-grid{grid-template-columns:1fr}
  .render-frame img{height:440px}
  .notes{grid-template-columns:1fr}
  .grid-specs{grid-template-columns:repeat(2,1fr)}
  .grid-ex{grid-template-columns:1fr}
  .grid-support{grid-template-columns:1fr}
  .board-card{grid-template-columns:1fr}
  .thumb img{height:200px}
}
@media (max-width:560px){
  .grid-specs{grid-template-columns:1fr}
  .step{grid-template-columns:1fr;gap:10px}
  .dl-desc-col{display:none}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .rgb-dot{animation:none;background:var(--cobalt-lt)}
  .site-nav a,.board-card{transition:none}
}