/* ============================================================
   ROBOTICSFAQ.COM — SHARED STYLES
   Design language: engineering workshop / test equipment.
   Charcoal panels, instrument-yellow accent, datasheet mono.
   Edit the tokens below to re-theme the whole site.
   ============================================================ */
:root {
  --bg:        #F2F4F5;
  --surface:   #FFFFFF;
  --panel:     #22262B;   /* dark instrument panel */
  --panel-2:   #2C3138;
  --ink:       #1B1F24;
  --muted:     #5B6570;
  --line:      #DCE1E6;
  --accent:    #FFC20E;   /* instrument yellow */
  --accent-dk: #B8880A;
  --ok:        #2E9E5B;
  --err:       #C63A2F;
  --radius:    10px;
  --font-display: "Saira Condensed", "Arial Narrow", sans-serif;
  --font-body: "IBM Plex Sans", system-ui, -apple-system, sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } * { transition: none !important; animation: none !important; } }

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
  font-size: 16px;
}

.wrap { max-width: 1080px; margin: 0 auto; padding: 0 20px; }

h1, h2, h3 { font-family: var(--font-display); letter-spacing: .01em; line-height: 1.15; margin: 0 0 .4em; }
h1 { font-size: clamp(2rem, 5vw, 3rem); text-transform: uppercase; }
h2 { font-size: clamp(1.4rem, 3vw, 1.9rem); text-transform: uppercase; }
h3 { font-size: 1.15rem; }
p { margin: 0 0 1em; }
a { color: var(--ink); }
.small { font-size: .85rem; color: var(--muted); }

/* ---------- Header ---------- */
.site-header {
  background: var(--panel);
  border-bottom: 3px solid var(--accent);
  position: sticky; top: 0; z-index: 50;
}
.header-inner { display: flex; align-items: center; justify-content: space-between; min-height: 62px; gap: 16px; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: #fff; }
.brand-mark {
  width: 26px; height: 26px; border-radius: 6px;
  background:
    radial-gradient(circle at 50% 50%, var(--panel) 3px, transparent 3.5px),
    var(--accent);
  border: 2px solid var(--accent-dk);
}
.brand-text { font-family: var(--font-display); font-size: 1.35rem; font-weight: 700; text-transform: uppercase; line-height: 1; }
.brand-text small { display: block; font-family: var(--font-body); font-size: .62rem; font-weight: 400; color: #B9C0C8; text-transform: none; letter-spacing: .02em; margin-top: 3px; }
.site-nav { display: flex; gap: 4px; }
.site-nav a {
  color: #DDE2E7; text-decoration: none; font-weight: 500; font-size: .95rem;
  padding: 8px 14px; border-radius: 6px;
}
.site-nav a:hover { background: var(--panel-2); color: #fff; }
.site-nav a.active { background: var(--accent); color: var(--panel); font-weight: 600; }
.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: 10px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: #fff; margin: 5px 0; border-radius: 2px; }

@media (max-width: 720px) {
  .nav-toggle { display: block; }
  .site-nav {
    display: none; position: absolute; top: 62px; left: 0; right: 0;
    background: var(--panel); flex-direction: column; padding: 8px 20px 16px;
    border-bottom: 3px solid var(--accent);
  }
  .site-nav.open { display: flex; }
  .site-nav a { padding: 12px 14px; }
}

/* ---------- Hero ---------- */
.hero { background: var(--surface); border-bottom: 1px solid var(--line); padding: 56px 0 48px; }
.hero .eyebrow {
  font-family: var(--font-mono); font-size: .75rem; font-weight: 600;
  color: var(--accent-dk); text-transform: uppercase; letter-spacing: .12em;
}
.hero p.lead { max-width: 560px; color: var(--muted); font-size: 1.05rem; }
.btn {
  display: inline-block; background: var(--accent); color: var(--panel);
  font-weight: 600; text-decoration: none; padding: 12px 22px;
  border-radius: var(--radius); border: 2px solid var(--accent-dk);
  font-size: 1rem; cursor: pointer; font-family: var(--font-body);
}
.btn:hover { background: #FFD04A; }
.btn:focus-visible, a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible {
  outline: 3px solid var(--accent-dk); outline-offset: 2px;
}

/* ---------- Sections & tool grid ---------- */
.section { padding: 48px 0; }
.tool-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 16px; margin-top: 20px; }
.tool-card {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 20px; text-decoration: none; display: block;
  transition: transform .12s ease, box-shadow .12s ease;
}
.tool-card.live:hover { transform: translateY(-3px); box-shadow: 0 6px 18px rgba(27,31,36,.08); border-color: var(--accent-dk); }
.tool-card.soon { opacity: .55; cursor: default; }
.tool-card h3 { margin: 10px 0 6px; }
.tool-card p { color: var(--muted); font-size: .9rem; margin: 0; }
.tool-status {
  font-family: var(--font-mono); font-size: .68rem; font-weight: 600; letter-spacing: .1em;
  color: var(--accent-dk);
}
.tool-card.soon .tool-status { color: var(--muted); }

/* ---------- Calculator layout ---------- */
.tool-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; align-items: start; margin-top: 24px; }
@media (max-width: 820px) { .tool-layout { grid-template-columns: 1fr; } }

.form-panel { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; }
.field { margin-bottom: 16px; }
.field label { display: block; font-weight: 600; font-size: .9rem; margin-bottom: 5px; }
.field .hint { font-size: .78rem; color: var(--muted); margin-top: 3px; }
.field input, .field select {
  width: 100%; padding: 10px 12px; font-size: 1rem; font-family: var(--font-body);
  border: 1px solid var(--line); border-radius: 8px; background: #FBFCFD; color: var(--ink);
}
.field input:focus, .field select:focus { border-color: var(--accent-dk); }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.error-msg { color: var(--err); font-size: .85rem; display: none; margin-top: 8px; }

/* ---------- Signature: the nameplate results panel ---------- */
.nameplate {
  background: var(--panel); color: #E8ECEF; border-radius: var(--radius);
  padding: 26px 24px; position: relative;
  border: 1px solid #3A4048;
  box-shadow: inset 0 1px 0 rgba(255,255,255,.06);
}
.nameplate::before, .nameplate::after,
.nameplate .screw-b::before, .nameplate .screw-b::after {
  content: ""; position: absolute; width: 9px; height: 9px; border-radius: 50%;
  background: radial-gradient(circle at 35% 35%, #7A828C, #454B53 70%);
}
.nameplate::before { top: 9px; left: 9px; }
.nameplate::after  { top: 9px; right: 9px; }
.nameplate .screw-b::before { bottom: 9px; left: 9px; }
.nameplate .screw-b::after  { bottom: 9px; right: 9px; }
.nameplate-head {
  font-family: var(--font-mono); font-size: .72rem; letter-spacing: .16em;
  color: var(--accent); text-transform: uppercase; margin-bottom: 14px;
}
.spec-row {
  display: flex; justify-content: space-between; align-items: baseline; gap: 12px;
  padding: 10px 0; border-bottom: 1px dashed #3A4048;
}
.spec-row:last-of-type { border-bottom: 0; }
.spec-label { font-size: .85rem; color: #AEB6BF; }
.spec-value { font-family: var(--font-mono); font-weight: 600; font-size: 1.05rem; color: #fff; white-space: nowrap; }
.spec-value.hot { color: var(--accent); font-size: 1.25rem; }
.spec-sub { font-family: var(--font-mono); font-size: .75rem; color: #8A929B; display: block; text-align: right; }
.nameplate .verdict {
  margin-top: 16px; padding: 12px 14px; border-radius: 8px;
  background: var(--panel-2); font-size: .88rem; color: #D5DAE0;
}
.copy-btn {
  margin-top: 14px; width: 100%; background: transparent; color: var(--accent);
  border: 1.5px solid var(--accent); border-radius: 8px; padding: 10px;
  font-family: var(--font-body); font-weight: 600; font-size: .9rem; cursor: pointer;
}
.copy-btn:hover { background: rgba(255,194,14,.12); }

/* ---------- Article / explanation content ---------- */
.content { max-width: 720px; }
.content h2 { margin-top: 1.8em; }
.content code, .formula {
  font-family: var(--font-mono); font-size: .9em;
  background: #E9EDF0; padding: 2px 6px; border-radius: 4px;
}
.formula { display: block; padding: 12px 16px; margin: 12px 0; border-left: 3px solid var(--accent); overflow-x: auto; }
.callout {
  background: var(--surface); border: 1px solid var(--line); border-left: 4px solid var(--accent);
  border-radius: 8px; padding: 14px 16px; margin: 16px 0; font-size: .95rem;
}
table.data { border-collapse: collapse; width: 100%; margin: 12px 0; font-size: .92rem; }
table.data th, table.data td { border: 1px solid var(--line); padding: 8px 12px; text-align: left; }
table.data th { background: var(--surface); font-family: var(--font-mono); font-size: .78rem; letter-spacing: .06em; text-transform: uppercase; }
table.data tr:nth-child(even) td { background: #FAFBFC; }

/* ---------- Parts / affiliate cards ---------- */
.parts-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 14px; margin-top: 16px; }
.part-card {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 16px; font-size: .9rem;
}
.part-card h4 { margin: 0 0 6px; font-size: .98rem; }
.part-card p { color: var(--muted); margin: 0 0 10px; }
.part-card a { color: var(--accent-dk); font-weight: 600; text-decoration: none; }
.part-card a:hover { text-decoration: underline; }

/* ---------- Blog list ---------- */
.post-list { list-style: none; padding: 0; margin: 20px 0 0; }
.post-list li { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 20px; margin-bottom: 12px; }
.post-list a { font-weight: 600; text-decoration: none; font-size: 1.05rem; }
.post-list a:hover { color: var(--accent-dk); }
.post-list .meta { font-family: var(--font-mono); font-size: .75rem; color: var(--muted); }

/* ---------- Ad slots (fill with AdSense code later) ---------- */
.ad-slot {
  min-height: 90px; margin: 28px 0; border: 1px dashed var(--line); border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  color: var(--muted); font-family: var(--font-mono); font-size: .72rem; letter-spacing: .1em;
}

/* ---------- Footer ---------- */
.site-footer { background: var(--panel); color: #B9C0C8; margin-top: 64px; border-top: 3px solid var(--accent); }
.footer-inner { display: grid; grid-template-columns: 2fr 1fr 1.4fr; gap: 32px; padding: 40px 20px; font-size: .88rem; }
@media (max-width: 720px) { .footer-inner { grid-template-columns: 1fr; gap: 20px; } }
.footer-brand { font-family: var(--font-display); font-size: 1.2rem; font-weight: 700; color: #fff; text-transform: uppercase; margin-bottom: 8px; }
.footer-head { font-family: var(--font-mono); font-size: .72rem; letter-spacing: .14em; text-transform: uppercase; color: var(--accent); margin-bottom: 10px; }
.footer-col a, .footer-col .soon { display: block; color: #B9C0C8; text-decoration: none; padding: 3px 0; }
.footer-col a:hover { color: #fff; }
.footer-col .soon { opacity: .5; }
.footer-col .small { color: #8A929B; }

/* ---------- Related posts box ---------- */
.related-box { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 20px; margin: 24px 0; }
.related-box a { display: block; padding: 5px 0; font-weight: 600; text-decoration: none; }
.related-box a:hover { color: var(--accent-dk); }

/* ---------- PID visualizer ---------- */
.pid-canvas-wrap { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; }
canvas#pid-plot { width: 100%; height: auto; display: block; }
.slider-field { margin-bottom: 14px; }
.slider-field label { display: flex; justify-content: space-between; font-weight: 600; font-size: .9rem; margin-bottom: 4px; }
.slider-field label output { font-family: var(--font-mono); color: var(--accent-dk); }
.slider-field input[type=range] { width: 100%; accent-color: var(--accent-dk); }
.preset-row { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 6px; }
.preset-row button { background: var(--bg); border: 1px solid var(--line); border-radius: 6px; padding: 6px 12px; font-family: var(--font-mono); font-size: .78rem; cursor: pointer; }
.preset-row button:hover { border-color: var(--accent-dk); }

/* ---------- Simple content pages ---------- */
.page-body { padding: 40px 0; }