/* Layout: porcelain page, product-led hero, a sapphire "cooling scale" as the signature visual, then evidence blocks a shopper and an AI answer engine can both quote. */
:root{
  --bg:#f8f4f2; --paper:#fffdfc; --ink:#26131b; --muted:#6f5a62; --line:#e7dad7;
  --rose:#9c4a60; --rose-soft:#f5e5e8; --ice:#2c5fc4; --ice-soft:#e7eefb; --good:#2f7a52; --warn:#a8641b; --bad:#a83a3a;
  --f-display:"Bodoni Moda", "Times New Roman", serif;
  --f-body:"Be Vietnam Pro", "Segoe UI", system-ui, sans-serif;
  --f-mono:"IBM Plex Mono", ui-monospace, Menlo, monospace;
}
@media (prefers-color-scheme: dark){:root:not([data-theme="light"]){
  --bg:#12070c; --paper:#1c0e14; --ink:#f6ecef; --muted:#bca6ae; --line:#3a2530;
  --rose:#e89cb0; --rose-soft:#2c141d; --ice:#93b5ff; --ice-soft:#151f38; --good:#7fd1a4; --warn:#f0b36a; --bad:#f09090; color-scheme:dark}}
:root[data-theme="dark"]{
  --bg:#12070c; --paper:#1c0e14; --ink:#f6ecef; --muted:#bca6ae; --line:#3a2530;
  --rose:#e89cb0; --rose-soft:#2c141d; --ice:#93b5ff; --ice-soft:#151f38; --good:#7fd1a4; --warn:#f0b36a; --bad:#f09090; color-scheme:dark}

*{box-sizing:border-box}
body{background:var(--bg);color:var(--ink);font-family:var(--f-body);font-size:16px;line-height:1.6;margin:0}
a{color:inherit}
.wrap{max-width:1160px;margin:0 auto;padding-left:max(16px,env(safe-area-inset-left,0px));padding-right:max(16px,env(safe-area-inset-right,0px))}
h1,h2,h3{line-height:1.15;text-wrap:balance;margin:0}
h2{font-size:clamp(1.7rem,3.4vw,2.5rem);font-weight:700;letter-spacing:-.01em}
h3{font-size:1.15rem;font-weight:600}
p{margin:0}
.lede{color:var(--muted);max-width:62ch}
.eyebrow{font-size:.75rem;letter-spacing:.14em;text-transform:uppercase;color:var(--rose);font-weight:600}
.serif{font-family:var(--f-display);font-style:italic;font-weight:500}
.mono{font-family:var(--f-mono);font-variant-numeric:tabular-nums}
section{padding-block:clamp(56px,8vw,96px)}
.sec-head{display:grid;gap:12px;margin-bottom:36px}
.btn{display:inline-flex;align-items:center;gap:8px;padding:13px 22px;border-radius:999px;font-weight:600;text-decoration:none;border:1px solid var(--ink);transition:transform .15s}
.btn:hover{transform:translateY(-1px)}
.btn:focus-visible,button:focus-visible,a:focus-visible{outline:2px solid var(--ice);outline-offset:3px}
.btn-solid{background:var(--ink);color:var(--bg)}
.btn-line{background:transparent}

/* top strip + nav */
.strip{background:var(--ink);color:var(--bg);font-size:.82rem;text-align:center}
.strip .wrap{padding-block:8px}
body::before{content:"";position:fixed;inset:0 0 auto;height:env(safe-area-inset-top,0px);z-index:10;background:var(--paper)}
header.nav{position:sticky;top:env(safe-area-inset-top,0px);z-index:9;background:color-mix(in srgb,var(--paper) 92%,transparent);backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
.nav .wrap{display:flex;align-items:center;gap:20px;padding-block:14px;flex-wrap:wrap}
.logo{display:flex;align-items:baseline;gap:8px;text-decoration:none}
.logo b{font-weight:700;letter-spacing:.12em}
.logo span{font-family:var(--f-display);font-style:italic;color:var(--rose);font-size:.95rem}
.nav ul{display:flex;gap:18px;list-style:none;margin:0 0 0 auto;padding:0;font-size:.92rem;flex-wrap:wrap}
.nav ul a{text-decoration:none;color:var(--muted)}
.nav ul a:hover{color:var(--ink)}
.lang{font-size:.8rem;color:var(--muted)}
.lang a{text-decoration:none;padding:2px 6px;border-radius:6px}
.lang a[aria-current]{background:var(--rose-soft);color:var(--rose);font-weight:600}

/* hero */
.hero{padding-block:clamp(40px,6vw,72px)}
.hero .wrap{display:grid;grid-template-columns:1.05fr .95fr;gap:clamp(28px,5vw,64px);align-items:center}
.hero h1{font-size:clamp(2.4rem,5.6vw,4.2rem);font-weight:700;letter-spacing:-.02em}
.hero h1 em{font-family:var(--f-display);font-weight:500;color:var(--ice)}
.hero-copy{display:grid;gap:22px;min-width:0}
.entity{border-left:2px solid var(--rose);padding-left:16px;color:var(--muted);font-size:.95rem;max-width:58ch}
.cta-row{display:flex;gap:12px;flex-wrap:wrap}
.trust{display:flex;flex-wrap:wrap;gap:8px 18px;font-size:.85rem;color:var(--muted)}
.trust li{list-style:none;display:flex;gap:6px;align-items:center}
.trust ul{display:contents}
.trust li::before{content:"";width:6px;height:6px;border-radius:50%;background:var(--good)}
.hero-media{position:relative;aspect-ratio:4/5;max-width:100%;border-radius:28px;background:radial-gradient(120% 90% at 70% 20%,var(--ice-soft),var(--rose-soft) 70%);overflow:hidden}
.hero-media img{width:100%;height:100%;object-fit:cover;display:block}
.device{position:absolute;inset:0;display:grid;place-items:center}
.device i{display:block;width:34%;aspect-ratio:1/3;border-radius:60px 60px 40px 40px;background:linear-gradient(160deg,#e9c9bf,#b98778);box-shadow:0 30px 60px -20px rgba(60,20,30,.45);position:relative;transform:rotate(-14deg)}
.device i::after{content:"";position:absolute;left:18%;right:18%;top:7%;height:16%;border-radius:12px;background:linear-gradient(180deg,#cfe0ff,#6f97e6);box-shadow:0 0 30px #8fb3ff}
.readout{position:absolute;left:16px;right:16px;bottom:16px;display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--line);border-radius:16px;overflow:hidden}
.readout div{background:var(--paper);padding:12px 14px}
.readout b{display:block;font-family:var(--f-mono);font-size:1.25rem;font-weight:500}
.readout small{color:var(--muted);font-size:.72rem}

/* lineup table */
.table-scroll{overflow-x:auto;border:1px solid var(--line);border-radius:20px;background:var(--paper)}
table{border-collapse:collapse;width:100%;min-width:720px;font-size:.93rem}
th,td{padding:14px 18px;text-align:left;border-bottom:1px solid var(--line);vertical-align:top}
thead th{font-size:.78rem;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);font-weight:600}
tbody th{font-weight:500;color:var(--muted);white-space:nowrap}
td.num{font-family:var(--f-mono);font-variant-numeric:tabular-nums}
.col-hero{background:var(--rose-soft)}
.model-name{font-weight:700;font-size:1.05rem;color:var(--ink);text-transform:none;letter-spacing:0;display:block}
.tag{display:inline-block;font-size:.7rem;padding:2px 8px;border-radius:999px;background:var(--ink);color:var(--bg);margin-top:4px;letter-spacing:.04em}
.price{font-family:var(--f-mono);font-size:1.1rem;color:var(--ink)}
.price s{color:var(--muted);font-size:.8rem;margin-left:6px}
.pick{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-top:20px}
.pick p{font-size:.92rem;color:var(--muted)}
.pick b{color:var(--ink)}

/* cooling scale */
.tech .wrap{display:grid;gap:40px}
.scale{background:var(--paper);border:1px solid var(--line);border-radius:24px;padding:28px clamp(18px,3vw,36px)}
.scale-bar{position:relative;height:14px;border-radius:999px;background:linear-gradient(90deg,var(--ice),#9cc0ff 45%,var(--rose-soft));margin:56px 0 46px}
.mark{position:absolute;top:50%;transform:translate(-50%,-50%);display:grid;justify-items:center}
.mark span{width:18px;height:18px;border-radius:50%;background:var(--paper);border:3px solid var(--ink)}
.mark label{position:absolute;bottom:26px;white-space:nowrap;font-size:.8rem;font-weight:600}
.mark em{position:absolute;top:24px;font-style:normal;font-family:var(--f-mono);font-size:.8rem;color:var(--muted)}
.ticks{display:flex;justify-content:space-between;font-family:var(--f-mono);font-size:.75rem;color:var(--muted)}
.pillars{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.pillar{display:grid;gap:10px;align-content:start;padding-top:18px;border-top:1px solid var(--ink)}
.pillar .big{font-family:var(--f-mono);font-size:2.3rem;line-height:1;color:var(--ice)}
.pillar p{color:var(--muted);font-size:.93rem}
.src{font-size:.75rem;color:var(--muted);opacity:.85}

/* routine */
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;counter-reset:s}
.step{background:var(--paper);border:1px solid var(--line);border-radius:18px;padding:20px;display:grid;gap:8px;align-content:start}
.step::before{counter-increment:s;content:"Bước " counter(s);font-size:.72rem;letter-spacing:.12em;text-transform:uppercase;color:var(--rose);font-weight:600}
.step p{font-size:.9rem;color:var(--muted)}
.plan{margin-top:20px;display:flex;flex-wrap:wrap;gap:10px;font-size:.9rem}
.plan span{padding:8px 14px;border-radius:999px;background:var(--ice-soft);color:var(--ink)}

/* quiz */
.quiz{background:var(--ink);color:var(--bg);border-radius:28px;padding:clamp(24px,4vw,48px)}
.quiz .lede{color:color-mix(in srgb,var(--bg) 70%,transparent)}
.quiz .eyebrow{color:var(--rose)}
.q-grid{display:grid;grid-template-columns:1fr 1fr;gap:28px;margin-top:28px}
fieldset{border:0;margin:0;padding:0;display:grid;gap:12px;min-width:0}
legend{font-weight:600;margin-bottom:10px}
.chips{display:flex;flex-wrap:wrap;gap:8px}
.chips input{position:absolute;opacity:0;pointer-events:none}
.chips label{display:flex;align-items:center;gap:8px;padding:8px 14px 8px 8px;border-radius:999px;border:1px solid color-mix(in srgb,var(--bg) 30%,transparent);cursor:pointer;font-size:.88rem}
.chips input:checked+label{background:var(--bg);color:var(--ink);border-color:var(--bg)}
.chips input:focus-visible+label{outline:2px solid var(--ice);outline-offset:2px}
.sw{width:22px;height:22px;border-radius:50%;border:1px solid rgba(255,255,255,.4)}
.result{margin-top:28px;padding:20px;border-radius:18px;background:color-mix(in srgb,var(--bg) 10%,transparent);display:grid;gap:8px}
.result b{font-size:1.15rem}
.result .verdict-good{color:#8fe0b2}.result .verdict-warn{color:#f5c07e}.result .verdict-bad{color:#f5a0a0}
.result small{opacity:.75}

/* app */
.app .wrap{display:grid;grid-template-columns:.9fr 1.1fr;gap:clamp(28px,5vw,64px);align-items:center}
.phone{justify-self:center;width:260px;max-width:100%;aspect-ratio:9/18.5;border-radius:40px;border:10px solid var(--ink);background:var(--paper);padding:22px 16px;display:grid;gap:12px;align-content:start;box-shadow:0 30px 60px -30px rgba(40,10,20,.5)}
.phone .ph-top{display:flex;justify-content:space-between;font-size:.72rem;color:var(--muted)}
.ring{width:120px;aspect-ratio:1;border-radius:50%;margin:6px auto;background:conic-gradient(var(--ice) 0 58%,var(--line) 58% 100%);display:grid;place-items:center}
.ring div{width:96px;aspect-ratio:1;border-radius:50%;background:var(--paper);display:grid;place-items:center;text-align:center;font-size:.7rem;color:var(--muted)}
.ring b{display:block;font-family:var(--f-mono);font-size:1.4rem;color:var(--ink)}
.ph-row{display:flex;justify-content:space-between;font-size:.78rem;padding:9px 12px;border-radius:12px;background:var(--bg)}
.ph-row b{font-family:var(--f-mono);font-weight:500}
.ph-note{font-size:.68rem;text-align:center;color:var(--muted)}
.feat{display:grid;gap:18px;margin-top:24px}
.feat div{display:grid;grid-template-columns:28px 1fr;gap:12px}
.feat i{font-style:normal;font-family:var(--f-mono);color:var(--ice)}
.feat p{color:var(--muted);font-size:.93rem}

/* compare */
.vs td:first-child{font-weight:500}
.yes{color:var(--good)}.mid{color:var(--warn)}

/* proof */
.proof-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--line);border:1px solid var(--line);border-radius:20px;overflow:hidden}
.proof-grid div{background:var(--paper);padding:20px;display:grid;gap:6px;align-content:start}
.proof-grid b{font-size:.95rem}
.proof-grid code{font-family:var(--f-mono);font-size:.78rem;color:var(--muted);word-break:break-all}
.guar{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-top:28px}
.guar div{display:grid;gap:6px;padding:20px;border-radius:18px;background:var(--rose-soft)}
.guar b{font-family:var(--f-mono);font-size:1.6rem;font-weight:500;color:var(--rose)}
.guar p{font-size:.88rem;color:var(--muted)}
.review{margin-top:28px;display:grid;grid-template-columns:auto 1fr;gap:18px;align-items:center;padding:22px;border:1px solid var(--line);border-radius:18px;background:var(--paper)}
.review .stars{font-family:var(--f-mono);color:var(--rose);font-size:1.2rem}
.review q{font-family:var(--f-display);font-style:italic;font-size:1.25rem}

/* faq */
.faq{display:grid;gap:10px;max-width:860px}
details{border:1px solid var(--line);border-radius:16px;background:var(--paper);padding:0 20px}
summary{cursor:pointer;padding:18px 0;font-weight:600;list-style:none;display:flex;justify-content:space-between;gap:16px}
summary::-webkit-details-marker{display:none}
summary::after{content:"+";font-family:var(--f-mono);color:var(--rose)}
details[open] summary::after{content:"–"}
details p{padding-bottom:18px;color:var(--muted)}

/* buy + footer */
.buy{background:var(--ink);color:var(--bg)}
.buy .wrap{display:grid;grid-template-columns:1fr 1fr;gap:32px;align-items:center}
.stores{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.stores a{display:grid;gap:4px;padding:18px;border-radius:16px;border:1px solid color-mix(in srgb,var(--bg) 25%,transparent);text-decoration:none}
.stores a:hover{background:color-mix(in srgb,var(--bg) 8%,transparent)}
.stores small{opacity:.7;font-size:.8rem}
footer{padding-block:40px;font-size:.85rem;color:var(--muted)}
footer .wrap{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:28px}
footer h4{margin:0 0 10px;color:var(--ink);font-size:.85rem}
footer ul{list-style:none;padding:0;margin:0;display:grid;gap:6px}
footer a{text-decoration:none}
footer a:hover{color:var(--ink)}
.legal{grid-column:1/-1;border-top:1px solid var(--line);padding-top:18px}

@media (max-width:900px){
  .hero .wrap,.app .wrap,.buy .wrap,.q-grid{grid-template-columns:1fr}
  .pillars,.pick{grid-template-columns:1fr}
  .steps,.guar{grid-template-columns:1fr 1fr}
  .proof-grid{grid-template-columns:1fr}
  footer .wrap{grid-template-columns:1fr 1fr}
  .nav ul{display:none}
  .hero-media{aspect-ratio:1/1}
}
@media (max-width:520px){
  .steps,.guar,.stores{grid-template-columns:1fr}
  .readout b{font-size:1rem}
  .review{grid-template-columns:1fr}
}
@media (prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important}}

/* ---- subpages ---- */
.crumbs{font-size:.82rem;color:var(--muted);display:flex;flex-wrap:wrap;gap:6px}
.crumbs a{text-decoration:none}.crumbs a:hover{color:var(--ink)}
.page-hero{padding-block:clamp(36px,6vw,64px) 8px}
.page-hero .wrap{display:grid;gap:16px}
.page-hero h1{font-size:clamp(2rem,4.6vw,3.2rem);font-weight:700;letter-spacing:-.015em;max-width:22ch}
.answer{background:var(--paper);border:1px solid var(--line);border-left:3px solid var(--ice);border-radius:14px;padding:18px 20px;max-width:72ch}
.answer b{display:block;font-size:.72rem;letter-spacing:.12em;text-transform:uppercase;color:var(--ice);margin-bottom:6px}
.page-body{padding-block:32px 72px}
.page-body .wrap{display:grid;gap:44px}
.prose{display:grid;gap:14px;max-width:72ch;min-width:0}
.prose h2{font-size:clamp(1.4rem,2.6vw,1.9rem)}
.prose ul,.prose ol{margin:0;padding-left:1.2em;display:grid;gap:6px}
.prose p,.prose li{color:var(--muted)}
.prose strong{color:var(--ink)}
.kv{display:grid;grid-template-columns:minmax(140px,1fr) 2fr;border:1px solid var(--line);border-radius:16px;overflow:hidden;background:var(--paper);max-width:860px;margin:0}
.kv dt,.kv dd{margin:0;padding:12px 16px;border-bottom:1px solid var(--line)}
.kv dt{color:var(--muted);font-size:.9rem}
.kv dd{font-family:var(--f-mono);font-size:.92rem;font-variant-numeric:tabular-nums}
.kv dt:last-of-type,.kv dd:last-of-type{border-bottom:0}
.cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:14px}
.cards a{display:grid;gap:6px;align-content:start;padding:18px;border:1px solid var(--line);border-radius:16px;background:var(--paper);text-decoration:none}
.cards a:hover{border-color:var(--ink)}
.cards small{color:var(--rose);font-size:.72rem;letter-spacing:.1em;text-transform:uppercase;font-weight:600}
.cards span{color:var(--muted);font-size:.9rem}
.updated{font-size:.8rem;color:var(--muted)}
@media (max-width:520px){.kv{grid-template-columns:1fr}.kv dt{border-bottom:0;padding-bottom:0}}