/* ============================================================
   HP Driver Hub — design system
   A precise, technical "spec sheet" aesthetic: deep navy,
   hairline rules, mono microlabels, generous whitespace.
   ============================================================ */

:root {
  --ink:     #111A24;
  --muted:   #5A6673;
  --soft:    #F6F8FA;
  --line:    #E3E8EE;
  --brand:   #0B3A6F;
  --brand-mid: #1160B0;
  --brand-soft:#EAF2FB;
  --signal:  #00A3A3;
  --signal-soft:#E4F7F7;
  --warn:    #A85B00;
  --warn-soft:#FCF2E4;
  --radius:  8px;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
html, body { overflow-x: hidden; }
body { -webkit-font-smoothing: antialiased; }

h1, h2, h3, p, li, dt, dd, summary, a { overflow-wrap: break-word; }

/* ---------- Skip link ---------- */
.skip-link {
  position: absolute; left: -9999px;
}
.skip-link:focus {
  left: 12px; top: 12px; z-index: 100;
  background: var(--ink); color: #fff;
  padding: .55rem 1rem; border-radius: var(--radius);
}

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: #E4E9F0;   /* deeper gray header */
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--line);
}

.brandmark {
  display: inline-flex; align-items: center; justify-content: center;
  width: 36px; height: 36px; flex: none;
  border-radius: var(--radius);
  background: var(--brand);
  color: #fff;
}
.brandmark svg { width: 22px; height: 22px; }

/* ---------- Hamburger ---------- */
.nav-toggle {
  display: inline-flex; flex-direction: column; justify-content: center;
  gap: 5px; width: 42px; height: 42px; padding: 0 10px;
  border: 1px solid var(--line); border-radius: var(--radius);
  background: #fff; cursor: pointer;
}
.nav-toggle span {
  display: block; height: 2px; width: 100%;
  background: var(--ink); border-radius: 2px;
  transition: transform .22s ease, opacity .18s ease;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.mobile-nav {
  display: grid; grid-template-rows: 0fr;
  border-top: 1px solid transparent;
  transition: grid-template-rows .26s ease;
}
.mobile-nav > div { overflow: hidden; }
.mobile-nav.is-open { grid-template-rows: 1fr; border-top-color: var(--line); }

.mobile-nav > div { background: #E4E9F0; }
.mobile-link {
  display: block; padding: .78rem 0;
  font-size: 15px; font-weight: 500; color: var(--muted);
  border-bottom: 1px solid var(--line);
  transition: color .15s ease;
}
.mobile-link:hover { color: var(--brand); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  padding: .68rem 1.25rem;
  border-radius: var(--radius);
  font-size: 14px; font-weight: 600; line-height: 1.2;
  border: 1px solid transparent;
  cursor: pointer; white-space: nowrap;
  transition: background .15s ease, border-color .15s ease, color .15s ease;
}
.btn-primary { background: var(--brand); color: #fff; border-color: var(--brand); }
.btn-primary:hover { background: var(--brand-mid); border-color: var(--brand-mid); }

.btn-ghost { background: #fff; color: var(--ink); border-color: var(--line); }
.btn-ghost:hover { border-color: var(--brand); color: var(--brand); }

/* ---------- Hero ---------- */
.hero {
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(180deg, #fff 0%, var(--soft) 100%);
}
.eyebrow {
  display: inline-block;
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px; font-weight: 500;
  text-transform: uppercase; letter-spacing: .16em;
  color: var(--brand);
  padding-left: 14px; position: relative;
}
.eyebrow::before {
  content: ""; position: absolute; left: 0; top: 50%;
  width: 8px; height: 2px; background: var(--signal);
}

/* ---------- Breadcrumb ---------- */
.breadcrumb {
  display: flex; flex-wrap: wrap; align-items: center; gap: .5rem;
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px; text-transform: uppercase; letter-spacing: .12em;
  color: var(--muted);
}
.breadcrumb a { transition: color .15s ease; }
.breadcrumb a:hover { color: var(--brand); }

/* ---------- Tags ---------- */
.tag {
  display: inline-block;
  padding: .18rem .5rem;
  border-radius: 4px; border: 1px solid transparent;
  font-family: "IBM Plex Mono", monospace;
  font-size: 10px; font-weight: 500;
  text-transform: uppercase; letter-spacing: .08em;
  white-space: nowrap;
}
.tag-brand  { background: var(--brand-soft);  color: var(--brand);  border-color: rgba(11,58,111,.18); }
.tag-signal { background: var(--signal-soft); color: #04706F;        border-color: rgba(0,163,163,.25); }
.tag-warn   { background: var(--warn-soft);   color: var(--warn);   border-color: rgba(168,91,0,.2); }

.meta-chip {
  display: inline-flex; align-items: center;
  padding: .6rem .85rem;
  border: 1px solid var(--line); border-radius: var(--radius);
  background: #fff;
  font-family: "IBM Plex Mono", monospace;
  font-size: 11.5px; color: var(--muted);
}

/* ---------- Spec card (the signature element) ---------- */
.spec-card {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #fff;
  padding: 1.4rem;
  /* the accent bar down the left edge is the site's visual signature */
  border-left: 3px solid var(--brand);
}
.spec-card__title {
  font-family: "IBM Plex Mono", monospace;
  font-size: 10.5px; font-weight: 500;
  text-transform: uppercase; letter-spacing: .14em;
  color: var(--muted);
}
.spec-row {
  display: flex; align-items: flex-start; justify-content: space-between;
  gap: 1rem; padding: .72rem 0;
  border-bottom: 1px solid var(--line);
}
.spec-row:last-child { border-bottom: 0; padding-bottom: 0; }
.spec-card dl { margin-top: .5rem; }
.spec-row dt { font-size: 13px; color: var(--muted); }
.spec-row dd { font-size: 13px; font-weight: 500; text-align: right; color: var(--ink); }

/* ---------- Cards ---------- */
.card {
  display: flex; flex-direction: column;
  padding: 1.4rem;
  border: 1px solid var(--line); border-radius: 12px;
  background: #fff;
  transition: border-color .18s ease, transform .18s ease;
}
.card:hover { border-color: var(--brand); transform: translateY(-2px); }
.card__title {
  margin-top: .85rem;
  font-size: 17px; font-weight: 600; line-height: 1.35;
  color: var(--ink);
}
.card:hover .card__title { color: var(--brand); }
.card__desc {
  margin-top: .5rem; flex: 1;
  font-size: 13.5px; line-height: 1.6; color: var(--muted);
}
.card__foot {
  display: flex; align-items: center; justify-content: space-between;
  margin-top: 1.2rem; padding-top: .9rem;
  border-top: 1px solid var(--line);
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px; color: var(--muted);
}
.card__arrow { transition: transform .18s ease, color .18s ease; }
.card:hover .card__arrow { color: var(--brand); transform: translateX(3px); }

/* ---------- OS tabs ---------- */
.os-tabs {
  display: inline-flex; gap: .25rem;
  margin-top: 1.5rem; padding: .25rem;
  border: 1px solid var(--line); border-radius: var(--radius);
  background: #fff;
  max-width: 100%; overflow-x: auto;
  scrollbar-width: none;
}
.os-tabs::-webkit-scrollbar { display: none; }
.os-tab {
  padding: .45rem 1rem;
  border-radius: 5px; border: 0;
  background: transparent;
  font-size: 14px; font-weight: 600; color: var(--muted);
  white-space: nowrap; cursor: pointer;
  transition: background .15s ease, color .15s ease;
}
.os-tab:hover { color: var(--ink); }
.os-tab.is-active { background: var(--brand); color: #fff; }

/* ---------- Download table ---------- */
.dl-table {
  border: 1px solid var(--line); border-radius: 12px;
  background: #fff; overflow: hidden;
}
.dl-row {
  display: flex; flex-direction: column; gap: .9rem;
  padding: 1.15rem 1.25rem;
  border-bottom: 1px solid var(--line);
}
.dl-row:last-child { border-bottom: 0; }
.dl-row__meta {
  display: flex; flex-wrap: wrap; gap: .4rem;
  margin-top: .6rem;
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px; color: var(--muted);
}
.dl-row__meta span {
  padding: .15rem .45rem;
  background: var(--soft); border-radius: 4px;
}
.dl-row__btn { width: 100%; }

@media (min-width: 640px) {
  .dl-row { flex-direction: row; align-items: center; justify-content: space-between; }
  .dl-row__btn { width: auto; flex: none; }
}

/* ---------- Steps ---------- */
.step {
  display: flex; gap: 1.1rem;
  padding: 1.15rem 0;
  border-bottom: 1px solid var(--line);
}
.step:last-child { border-bottom: 0; }
.step__num {
  display: flex; align-items: center; justify-content: center;
  width: 30px; height: 30px; flex: none;
  border-radius: 6px;
  background: var(--brand-soft); color: var(--brand);
  font-family: "IBM Plex Mono", monospace;
  font-size: 13px; font-weight: 500;
}
.step__title { font-size: 15.5px; font-weight: 600; color: var(--ink); }
.step__desc  { margin-top: .3rem; font-size: 14.5px; line-height: 1.65; color: var(--muted); }

/* ---------- Checklist items ---------- */
.check-item {
  position: relative;
  padding-left: 1.5rem;
  font-size: 15px; line-height: 1.7; color: rgba(17,26,36,.82);
}
.check-item::before {
  content: ""; position: absolute;
  left: 0; top: .62em;
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--signal);
}

/* ---------- FAQ ---------- */
.faq {
  border: 1px solid var(--line); border-radius: 12px;
  background: #fff; overflow: hidden;
}
.faq__item { border-bottom: 1px solid var(--line); }
.faq__item:last-child { border-bottom: 0; }
.faq__item summary {
  display: flex; align-items: center; justify-content: space-between; gap: 1rem;
  padding: 1.05rem 1.25rem;
  font-size: 15px; font-weight: 500; color: var(--ink);
  cursor: pointer; list-style: none;
}
.faq__item summary::-webkit-details-marker { display: none; }
.faq__item summary:hover { color: var(--brand); }
.faq__icon {
  flex: none;
  font-family: "IBM Plex Mono", monospace;
  color: var(--muted);
  transition: transform .2s ease, color .2s ease;
}
.faq__item[open] .faq__icon { transform: rotate(45deg); color: var(--brand); }
.faq__item p {
  padding: 0 1.25rem 1.15rem;
  font-size: 14.5px; line-height: 1.7; color: var(--muted);
}

/* ---------- Prose (legal pages) ---------- */
.prose { font-size: 15.5px; line-height: 1.8; color: rgba(17,26,36,.8); }
.prose p { margin-top: 1rem; }
.prose h2 {
  margin-top: 2.2rem;
  font-size: 19px; font-weight: 700; letter-spacing: -.01em;
  color: var(--ink);
}
.prose ul { margin-top: 1rem; padding-left: 1.2rem; list-style: disc; }
.prose li { margin-top: .45rem; }
.prose strong { font-weight: 600; color: var(--ink); }
.prose a, .link {
  color: var(--brand); text-decoration: underline; text-underline-offset: 2px;
}
.prose a:hover, .link:hover { color: var(--brand-mid); }

/* ---------- Forms ---------- */
.form-label {
  display: block; margin-bottom: .4rem;
  font-size: 13.5px; font-weight: 600; color: var(--ink);
}
.form-input {
  width: 100%;
  padding: .72rem .9rem;
  border: 1px solid var(--line); border-radius: var(--radius);
  background: #fff;
  font-family: inherit; font-size: 15px; color: var(--ink);
  transition: border-color .15s ease, box-shadow .15s ease;
}
.form-input::placeholder { color: #9AA5B1; }
.form-input:focus {
  outline: none;
  border-color: var(--brand);
  box-shadow: 0 0 0 3px rgba(11,58,111,.1);
}
textarea.form-input { min-height: 140px; resize: vertical; }

/* Honeypot — hidden from humans, filled by bots */
.hp-field {
  position: absolute !important;
  left: -9999px !important;
  width: 1px; height: 1px; overflow: hidden;
}

.alert { padding: 1.15rem 1.25rem; border-radius: var(--radius); border: 1px solid; }
.alert-ok  { background: #ECFDF5; border-color: #A7F3D0; color: #065F46; }
.alert-bad { background: #FEF2F2; border-color: #FECACA; color: #991B1B; }

/* ---------- Focus visibility ---------- */
a:focus-visible, button:focus-visible, summary:focus-visible,
input:focus-visible, textarea:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------- Small screens ---------- */
@media (max-width: 640px) {
  .btn { width: 100%; }
  .meta-chip { justify-content: center; }
  .spec-card { padding: 1.15rem; }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; scroll-behavior: auto !important; }
}

/* ---------- Footer: slightly deeper gray so it separates from content ---------- */
footer.bg-soft, footer {
  background: #DDE3EC;
  border-top: 1px solid var(--line);
}