/* ==========================================================================
   ZCWA Robot Vacuum — Official Website
   Design tokens
   ink      #0B1725  deep navy, drawn from the BR151 brushed-blue shell in shadow
   steel    #3C6E9E  the product's own body colour
   signal   #0A8F63  the green status LED on the robot's lid — used only for action
   haze     #EEF2F6  the cool light of a hard floor under daylight
   line     #D5DDE6  hairline
   ========================================================================== */

:root {
  --ink: #0b1725;
  --ink-soft: #23384f;
  --steel: #3c6e9e;
  --steel-dark: #24486b;
  --signal: #0a8f63;
  --signal-dark: #077048;
  --haze: #eef2f6;
  --haze-deep: #e2e9f0;
  --paper: #ffffff;
  --line: #d5dde6;
  --muted: #5a6b7d;
  --warn: #b4531f;

  --font-display: "Archivo", "Helvetica Neue", Arial, sans-serif;
  --font-body: "IBM Plex Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, monospace;

  --wrap: 1120px;
  --wrap-narrow: 760px;
  --gap: clamp(1rem, 3vw, 2rem);
  --sect: clamp(3.5rem, 8vw, 6.5rem);
  --radius: 4px;
}

/* ---------- reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 1.0625rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--steel-dark); text-underline-offset: 3px; }
a:hover { color: var(--ink); }

:focus-visible {
  outline: 3px solid var(--signal);
  outline-offset: 2px;
}

.wrap { width: 100%; max-width: var(--wrap); margin-inline: auto; padding-inline: var(--gap); }
.wrap--narrow { max-width: var(--wrap-narrow); }

.skip {
  position: absolute; left: -9999px; top: 0; z-index: 100;
  background: var(--ink); color: #fff; padding: .75rem 1.25rem;
}
.skip:focus { left: 0; }

/* ---------- typography ---------- */
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.02em;
  margin: 0 0 .6em;
  text-wrap: balance;
}
h1 { font-size: clamp(2.1rem, 5.2vw, 3.5rem); font-weight: 900; }
h2 { font-size: clamp(1.6rem, 3.4vw, 2.35rem); margin-top: 0; }
h3 { font-size: clamp(1.2rem, 2.2vw, 1.5rem); }
h4 { font-size: 1.0625rem; letter-spacing: -0.01em; }
p { margin: 0 0 1.1em; }
p, li { text-wrap: pretty; }

.lede { font-size: clamp(1.1rem, 2vw, 1.3rem); line-height: 1.55; color: var(--ink-soft); }

/* the eyebrow encodes what kind of information follows, not decoration */
.eyebrow {
  font-family: var(--font-mono);
  font-size: .75rem;
  font-weight: 500;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--steel);
  margin: 0 0 .9rem;
  display: block;
}

.answer {
  font-size: 1.1rem;
  line-height: 1.6;
  border-left: 3px solid var(--signal);
  padding: .1rem 0 .1rem 1.15rem;
  margin: 0 0 1.6rem;
}

/* ---------- header ---------- */
.masthead {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,.94);
  backdrop-filter: saturate(1.6) blur(10px);
  border-bottom: 1px solid var(--line);
}
.masthead__bar {
  display: flex; align-items: center; gap: 1rem;
  min-height: 70px;
}
.brand { display: flex; align-items: center; gap: .7rem; text-decoration: none; color: var(--ink); flex: 0 0 auto; }
.brand svg { width: 38px; height: 38px; flex: 0 0 auto; }
.brand__name { font-family: var(--font-display); font-weight: 900; font-size: 1.02rem; letter-spacing: -.02em; line-height: 1.1; display: block; }
.brand__tag { font-family: var(--font-mono); font-size: .62rem; letter-spacing: .17em; text-transform: uppercase; color: var(--steel); display: block; }

.nav { margin-left: auto; }
.nav ul { display: flex; gap: 1.4rem; list-style: none; margin: 0; padding: 0; }
.nav a {
  font-size: .93rem; font-weight: 500; text-decoration: none; color: var(--ink-soft);
  padding: .35rem 0; border-bottom: 2px solid transparent;
}
.nav a:hover, .nav a[aria-current="page"] { color: var(--ink); border-bottom-color: var(--signal); }

.nav-toggle { display: none; }

@media (max-width: 900px) {
  .nav-toggle {
    display: inline-flex; align-items: center; gap: .5rem; margin-left: auto;
    background: none; border: 1px solid var(--line); border-radius: var(--radius);
    font-family: var(--font-mono); font-size: .72rem; letter-spacing: .12em; text-transform: uppercase;
    padding: .55rem .8rem; color: var(--ink); cursor: pointer;
  }
  .nav {
    display: none; margin: 0;
    position: absolute; left: 0; right: 0; top: 100%;
    background: var(--paper); border-bottom: 1px solid var(--line);
    padding: .5rem var(--gap) 1.25rem;
  }
  .nav[data-open="true"] { display: block; }
  .nav ul { flex-direction: column; gap: 0; }
  .nav li { border-bottom: 1px solid var(--line); }
  .nav a { display: block; padding: .85rem 0; border-bottom: none; }
}

/* ---------- disclosure ---------- */
/* The Amazon statement now lives only at the end of the site, so it gets its
   own band above the small print rather than being buried inside it. */
.footer__disclosure {
  border-top: 1px solid #22384f;
  padding: 1.5rem 0 1.25rem;
  margin-bottom: .25rem;
}
.footer__disclosure p {
  margin: 0;
  font-size: .93rem;
  line-height: 1.55;
  color: #e4ecf4;
  max-width: 62ch;
}
.disclosure-inline {
  background: var(--haze);
  border: 1px solid var(--line);
  border-left: 3px solid var(--steel);
  padding: .85rem 1.1rem;
  font-size: .88rem;
  line-height: 1.55;
  color: var(--ink-soft);
  margin: 0 0 2rem;
  border-radius: var(--radius);
}
.disclosure-inline strong { color: var(--ink); }

/* ---------- hero ---------- */
.hero {
  position: relative;
  background: linear-gradient(180deg, var(--haze) 0%, #f7f9fb 62%, var(--paper) 100%);
  overflow: hidden;
  padding: clamp(2.5rem, 6vw, 4.5rem) 0 clamp(2rem, 5vw, 3.5rem);
  border-bottom: 1px solid var(--line);
}
.hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.02fr);
  gap: clamp(1.5rem, 4vw, 3.5rem);
  align-items: center;
  position: relative;
  z-index: 2;
}
@media (max-width: 860px) { .hero__grid { grid-template-columns: 1fr; } }

.hero h1 { margin-bottom: .45em; }
.hero h1 em { font-style: normal; color: var(--steel-dark); }

/* SIGNATURE: the coverage path. The BR151 navigates a Z-shaped
   boustrophedon route; that route is the page's opening image. */
.coverage {
  position: relative;
  aspect-ratio: 1 / 1;
  max-width: 560px;
  margin-inline: auto;
  width: 100%;
}
.coverage__svg { position: absolute; inset: 0; width: 100%; height: 100%; }
.coverage__path {
  fill: none;
  stroke: var(--signal);
  stroke-width: 1.6;
  stroke-linecap: round;
  stroke-linejoin: round;
  opacity: .55;
  stroke-dasharray: 1400;
  stroke-dashoffset: 1400;
  animation: trace 6s cubic-bezier(.42,0,.58,1) .35s forwards;
}
.coverage__plan { fill: none; stroke: var(--line); stroke-width: 1; }
.coverage__dot {
  fill: var(--signal);
  opacity: 0;
  animation: pop .5s ease 6s forwards;
}
.coverage__img {
  position: absolute;
  inset: 14% 12% auto 12%;
  filter: drop-shadow(0 26px 40px rgba(11,23,37,.22));
}
.coverage__img img { width: 100%; height: auto; }

@keyframes trace { to { stroke-dashoffset: 0; } }
@keyframes pop { from { opacity: 0; transform: scale(.4); } to { opacity: 1; transform: scale(1); } }
@media (prefers-reduced-motion: reduce) {
  .coverage__path { animation: none; stroke-dashoffset: 0; opacity: .35; }
  .coverage__dot { animation: none; opacity: 1; }
}
@media (max-width: 860px) {
  .coverage { max-width: 420px; }
  .coverage__img { inset: 16% 14% auto 14%; }
}

/* ---------- spec strip ---------- */
.specstrip {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--paper);
}
.specstrip div { padding: 1.15rem .9rem; border-right: 1px solid var(--line); }
.specstrip div:last-child { border-right: none; }
.specstrip dt, .specstrip .k {
  font-family: var(--font-mono); font-size: .68rem; letter-spacing: .13em;
  text-transform: uppercase; color: var(--muted); margin: 0 0 .3rem;
}
.specstrip .v { font-family: var(--font-display); font-weight: 800; font-size: clamp(1.1rem, 2.3vw, 1.5rem); letter-spacing: -.02em; }
@media (max-width: 780px) {
  .specstrip { grid-template-columns: repeat(2, 1fr); }
  .specstrip div { border-bottom: 1px solid var(--line); }
  .specstrip div:nth-child(2n) { border-right: none; }
}

/* ---------- sections ---------- */
.section { padding: var(--sect) 0; }
.section--haze { background: var(--haze); }
.section--tight { padding-block: clamp(2.5rem, 5vw, 3.5rem); }
.section__head { max-width: 42rem; margin-bottom: clamp(1.8rem, 4vw, 2.8rem); }

/* ---------- feature rows ---------- */
.feature {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: clamp(1.5rem, 4vw, 3.5rem);
  align-items: center;
  padding-block: clamp(1.75rem, 4vw, 2.75rem);
  border-bottom: 1px solid var(--line);
}
.feature:last-child { border-bottom: none; }
.feature:nth-child(even) .feature__media { order: -1; }
@media (max-width: 800px) {
  .feature { grid-template-columns: 1fr; }
  .feature:nth-child(even) .feature__media { order: 0; }
}
.feature__media img { border-radius: var(--radius); border: 1px solid var(--line); background: var(--paper); }
.feature figcaption {
  font-family: var(--font-mono); font-size: .72rem; color: var(--muted);
  margin-top: .6rem; line-height: 1.5;
}
.feature ul { padding-left: 1.1rem; margin: 0; }
.feature li { margin-bottom: .4rem; }

/* ---------- product card ---------- */
.card {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 1px 0 rgba(11,23,37,.04), 0 14px 34px -22px rgba(11,23,37,.35);
}
.card__top {
  display: grid; grid-template-columns: minmax(0, .95fr) minmax(0, 1.05fr);
  gap: clamp(1.25rem, 3vw, 2.5rem);
  padding: clamp(1.25rem, 3vw, 2.25rem);
  align-items: center;
}
@media (max-width: 760px) { .card__top { grid-template-columns: 1fr; } }
.card__img { background: var(--haze); border-radius: var(--radius); padding: .5rem; }
.card__title { font-size: clamp(1.25rem, 2.6vw, 1.65rem); margin-bottom: .5rem; }
.card__model {
  font-family: var(--font-mono); font-size: .72rem; letter-spacing: .12em;
  text-transform: uppercase; color: var(--muted); display: block; margin-bottom: .55rem;
}
.card ul { padding-left: 1.05rem; margin: 0 0 1.25rem; }
.card li { margin-bottom: .35rem; font-size: .97rem; }
.card__foot {
  border-top: 1px solid var(--line);
  background: var(--haze);
  padding: 1.4rem clamp(1.25rem, 3vw, 2.25rem) 1.6rem;
  text-align: center;
}
.card__note {
  font-family: var(--font-mono); font-size: .7rem; letter-spacing: .1em;
  text-transform: uppercase; color: var(--muted); margin: .85rem 0 0;
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .55rem;
  font-family: var(--font-display); font-weight: 800; font-size: 1.02rem; letter-spacing: -.01em;
  background: var(--signal); color: #fff; text-decoration: none;
  padding: .95rem 2.4rem; border: none; border-radius: var(--radius);
  min-height: 52px; cursor: pointer;
  transition: background .16s ease, transform .16s ease;
}
.btn:hover { background: var(--signal-dark); color: #fff; transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn--block { display: flex; width: 100%; max-width: 22rem; margin-inline: auto; }
.btn--ghost {
  background: transparent; color: var(--ink); border: 1.5px solid var(--ink);
}
.btn--ghost:hover { background: var(--ink); color: #fff; }
.btn svg { flex: 0 0 auto; }

/* hero: primary and secondary side by side, wrapping on narrow screens */
.cta-row { display: flex; flex-wrap: wrap; gap: .75rem; }
.cta-row .btn { flex: 0 1 auto; }
@media (max-width: 460px) { .cta-row .btn { flex: 1 1 100%; } }

/* the CTA is always centred in a card, per the card contract */
.cta-center { text-align: center; }
.cta-center--multi {
  display: flex; flex-wrap: wrap; gap: .7rem; justify-content: center;
}
.cta-center--multi .card__note { flex: 1 0 100%; }

/* ---------- tables ---------- */
.table-scroll { overflow-x: auto; -webkit-overflow-scrolling: touch; margin-bottom: 1.75rem; }
table { width: 100%; border-collapse: collapse; font-size: .95rem; }
caption {
  text-align: left; font-family: var(--font-mono); font-size: .72rem;
  letter-spacing: .12em; text-transform: uppercase; color: var(--muted);
  padding-bottom: .7rem;
}
th, td { text-align: left; padding: .75rem .9rem; border-bottom: 1px solid var(--line); vertical-align: top; }
thead th {
  font-family: var(--font-mono); font-size: .7rem; letter-spacing: .1em; text-transform: uppercase;
  color: var(--muted); font-weight: 400; border-bottom: 1.5px solid var(--ink);
}
tbody th { font-weight: 600; width: 38%; }
tbody td.num, .mono { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }
tbody tr:last-child th, tbody tr:last-child td { border-bottom: none; }

/* ---------- pros / cons ---------- */
.verdict { display: grid; grid-template-columns: 1fr 1fr; gap: 1.25rem; margin-bottom: 2rem; }
@media (max-width: 700px) { .verdict { grid-template-columns: 1fr; } }
.verdict > div { border: 1px solid var(--line); border-radius: var(--radius); padding: 1.25rem 1.4rem; background: var(--paper); }
.verdict h3 { font-size: 1rem; font-weight: 800; margin-bottom: .8rem; display: flex; align-items: center; gap: .5rem; }
.verdict--pro { border-top: 3px solid var(--signal); }
.verdict--con { border-top: 3px solid var(--warn); }
.verdict ul { margin: 0; padding-left: 1.1rem; }
.verdict li { margin-bottom: .5rem; font-size: .95rem; }

/* ---------- steps ---------- */
.steps { list-style: none; counter-reset: s; margin: 0 0 2rem; padding: 0; }
.steps li {
  counter-increment: s;
  position: relative;
  padding: 0 0 1.35rem 3.1rem;
  border-left: 1px solid var(--line);
  margin-left: 1rem;
}
.steps li::before {
  content: counter(s, decimal-leading-zero);
  position: absolute; left: -1rem; top: 0;
  width: 2rem; height: 2rem; border-radius: 50%;
  background: var(--ink); color: #fff;
  font-family: var(--font-mono); font-size: .72rem;
  display: grid; place-items: center;
}
.steps li:last-child { border-left-color: transparent; padding-bottom: 0; }
.steps strong { display: block; font-family: var(--font-display); font-weight: 800; font-size: 1.05rem; margin-bottom: .25rem; }

/* ---------- FAQ ---------- */
.faq { border-top: 1.5px solid var(--ink); }
.faq details { border-bottom: 1px solid var(--line); }
.faq summary {
  cursor: pointer; list-style: none;
  padding: 1.1rem 2.5rem 1.1rem 0;
  font-family: var(--font-display); font-weight: 800; font-size: 1.05rem;
  letter-spacing: -.01em; position: relative;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; position: absolute; right: .3rem; top: 50%; transform: translateY(-50%);
  font-family: var(--font-mono); font-size: 1.35rem; color: var(--steel); line-height: 1;
}
.faq details[open] summary::after { content: "–"; }
.faq summary:hover { color: var(--steel-dark); }
.faq__a { padding: 0 0 1.3rem; max-width: 60ch; }
.faq__a p:last-child { margin-bottom: 0; }

/* ---------- link tiles ---------- */
.tiles { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 1px; background: var(--line); border: 1px solid var(--line); }
.tiles a {
  background: var(--paper); padding: 1.5rem 1.4rem; text-decoration: none; color: var(--ink);
  display: block; transition: background .15s ease;
}
.tiles a:hover { background: var(--haze); }
.tiles h3 { font-size: 1.05rem; margin-bottom: .3rem; }
.tiles p { font-size: .9rem; color: var(--muted); margin: 0; }
.tiles .arrow { font-family: var(--font-mono); color: var(--steel); }

/* ---------- gallery ---------- */
.gallery { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 1rem; }
.gallery figure { margin: 0; }
.gallery img { border: 1px solid var(--line); border-radius: var(--radius); }
.gallery figcaption { font-family: var(--font-mono); font-size: .7rem; color: var(--muted); margin-top: .5rem; line-height: 1.45; }

/* ---------- breadcrumbs ---------- */
.crumbs { font-family: var(--font-mono); font-size: .74rem; letter-spacing: .06em; padding: 1.1rem 0 0; color: var(--muted); }
.crumbs ol { list-style: none; display: flex; flex-wrap: wrap; gap: .45rem; margin: 0; padding: 0; }
.crumbs a { color: var(--muted); }
.crumbs a:hover { color: var(--ink); }
.crumbs li + li::before { content: "/"; margin-right: .45rem; color: var(--line); }

/* ---------- meta line ---------- */
.pagemeta {
  font-family: var(--font-mono); font-size: .73rem; color: var(--muted);
  border-top: 1px solid var(--line); border-bottom: 1px solid var(--line);
  padding: .7rem 0; margin: 0 0 2rem; display: flex; flex-wrap: wrap; gap: 1.2rem;
}

/* ---------- prose ---------- */
.prose h2 { margin-top: 2.6rem; }
.prose h3 { margin-top: 1.9rem; }
.prose > *:first-child { margin-top: 0; }
.prose ul, .prose ol { padding-left: 1.25rem; margin-bottom: 1.3rem; }
.prose li { margin-bottom: .45rem; }
.prose blockquote {
  margin: 1.6rem 0; padding: .2rem 0 .2rem 1.2rem;
  border-left: 3px solid var(--steel); color: var(--ink-soft); font-size: 1.03rem;
}

/* ---------- sticky mobile CTA ---------- */
.sticky-cta { display: none; }
@media (max-width: 720px) {
  .sticky-cta {
    display: block; position: fixed; left: 0; right: 0; bottom: 0; z-index: 60;
    background: rgba(255,255,255,.96); backdrop-filter: blur(8px);
    border-top: 1px solid var(--line);
    padding: .6rem var(--gap) calc(.6rem + env(safe-area-inset-bottom));
  }
  .sticky-cta .btn { width: 100%; min-height: 50px; }
  body { padding-bottom: 4.5rem; }
}

/* ---------- footer ---------- */
.footer { background: var(--ink); color: #b7c6d6; padding: clamp(3rem, 6vw, 4.5rem) 0 2rem; font-size: .92rem; }
.footer a { color: #e4ecf4; }
.footer a:hover { color: #fff; }
.footer__grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 2rem; margin-bottom: 2.5rem; }
@media (max-width: 860px) { .footer__grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 520px) { .footer__grid { grid-template-columns: 1fr; } }
.footer h4 { color: #fff; font-size: .74rem; font-family: var(--font-mono); font-weight: 500; letter-spacing: .14em; text-transform: uppercase; margin-bottom: .9rem; }
.footer ul { list-style: none; margin: 0; padding: 0; }
.footer li { margin-bottom: .5rem; }
.footer__brand svg { width: 42px; height: 42px; margin-bottom: .9rem; }
.footer__legal { padding-top: 1.25rem; font-size: .82rem; line-height: 1.6; color: #8ea3b8; }
.footer address { font-style: normal; line-height: 1.7; }

/* ---------- cookie banner ---------- */
.cookiebar {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 80;
  background: var(--ink); color: #dce6f0;
  padding: 1.1rem var(--gap) calc(1.1rem + env(safe-area-inset-bottom));
  display: none; box-shadow: 0 -8px 30px rgba(11,23,37,.25);
}
.cookiebar[data-show="true"] { display: block; }
.cookiebar__in { max-width: var(--wrap); margin-inline: auto; display: flex; flex-wrap: wrap; gap: 1rem; align-items: center; }
.cookiebar p { margin: 0; font-size: .88rem; flex: 1 1 22rem; line-height: 1.5; }
.cookiebar a { color: #fff; }
.cookiebar__btns { display: flex; gap: .6rem; }
.cookiebar button {
  font-family: var(--font-display); font-weight: 700; font-size: .88rem;
  padding: .6rem 1.4rem; border-radius: var(--radius); cursor: pointer; border: 1px solid #4a627c;
  background: transparent; color: #dce6f0;
}
.cookiebar button.is-accept { background: var(--signal); border-color: var(--signal); color: #fff; }
.cookiebar button:hover { border-color: #fff; }

/* ---------- misc ---------- */
.notice {
  background: #fff8f2; border: 1px solid #f0d6c0; border-left: 3px solid var(--warn);
  padding: 1rem 1.2rem; border-radius: var(--radius); font-size: .93rem; margin-bottom: 1.75rem;
}
.notice p:last-child { margin-bottom: 0; }
.vis-hidden { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
hr { border: none; border-top: 1px solid var(--line); margin: 2.5rem 0; }