:root{
  --navy:#0d2238; --navy-2:#14324f; --steel:#2b5d86; --accent:#f0a400; --accent-d:#c98800;
  --teal:#1aa39a; --ink:#1b2430; --muted:#5b6876; --line:#dfe5ec; --bg:#f4f7fa; --white:#fff;
  --radius:12px; --shadow:0 10px 30px rgba(13,34,56,.08);
  --font:-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans CJK SC","Noto Sans SC","Source Han Sans SC",sans-serif;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:72px}
body{margin:0;font-family:var(--font);color:var(--ink);background:var(--white);line-height:1.7;-webkit-font-smoothing:antialiased}
img{max-width:100%;display:block;height:auto}
a{color:var(--steel)}
h1,h2,h3,h4{line-height:1.3;margin:0}
.wrap{max-width:1180px;margin:0 auto;padding:0 20px}
.eyebrow{display:inline-block;font-size:.82rem;font-weight:700;letter-spacing:.12em;color:var(--accent-d);margin:0 0 10px;text-transform:uppercase}
.eyebrow::before{content:"";display:inline-block;width:18px;height:3px;background:var(--accent);vertical-align:middle;margin-right:8px;border-radius:2px}

/* buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;padding:12px 22px;border-radius:8px;font-weight:700;font-size:1rem;text-decoration:none;border:2px solid transparent;cursor:pointer;font-family:inherit;transition:.2s}
.btn-primary{background:var(--accent);color:#1b1300}
.btn-primary:hover{background:var(--accent-d);color:#fff}
.btn-ghost{border-color:rgba(255,255,255,.5);color:#fff}
.btn-ghost:hover{background:rgba(255,255,255,.1)}
.btn-ghost-dark{border-color:var(--line);color:var(--navy);background:#fff}
.btn-ghost-dark:hover{border-color:var(--steel)}
.btn-block{width:100%}

/* topbar */
.topbar{position:sticky;top:0;z-index:50;background:rgba(13,34,56,.97);backdrop-filter:blur(6px);color:#fff;box-shadow:0 2px 10px rgba(0,0,0,.15)}
.topbar-inner{display:flex;align-items:center;justify-content:space-between;height:64px}
.brand{display:flex;align-items:center;gap:10px;color:#fff;text-decoration:none}
.brand-mark{display:flex;align-items:center}
.brand-mark img{height:40px;width:auto;display:block}
.brand-text{display:flex;flex-direction:column;line-height:1.2}
.brand-text strong{font-size:1.08rem;letter-spacing:.04em}
.brand-text small{font-size:.72rem;color:#9fb3c8}
.nav{display:flex;align-items:center;gap:4px}
.nav a{color:#d6e2ee;text-decoration:none;padding:8px 12px;border-radius:6px;font-size:.95rem}
.nav a:hover{color:#fff;background:rgba(255,255,255,.08)}
.nav .nav-call{background:var(--accent);color:#1b1300;font-weight:700;margin-left:8px}
.nav .nav-call:hover{background:var(--accent-d);color:#fff}
.nav-toggle{display:none;background:none;border:0;padding:10px;cursor:pointer}
.nav-toggle span{display:block;width:24px;height:2px;background:#fff;margin:5px 0;transition:.2s}

/* hero */
.hero{background:radial-gradient(1200px 500px at 85% 20%,rgba(43,93,134,.55),transparent 60%),linear-gradient(135deg,var(--navy) 0%,#0a1a2b 100%);color:#fff;overflow:hidden;position:relative}
.hero::after{content:"";position:absolute;inset:0;background-image:linear-gradient(rgba(255,255,255,.04) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.04) 1px,transparent 1px);background-size:40px 40px;pointer-events:none}
.hero-inner{display:grid;grid-template-columns:1.15fr .85fr;gap:40px;align-items:center;padding:72px 20px 80px;position:relative;z-index:1}
.hero h1{font-size:clamp(2rem,4.4vw,3.2rem);font-weight:800;letter-spacing:.02em}
.hero h1 span{color:var(--accent)}
.hero .eyebrow{color:#ffd56a}
.lead{color:#c7d5e3;font-size:1.06rem;margin:18px 0 22px;max-width:36em}
.hero-tags{list-style:none;padding:0;margin:0 0 28px;display:flex;flex-wrap:wrap;gap:8px}
.hero-tags li{border:1px solid rgba(255,255,255,.22);background:rgba(255,255,255,.06);padding:5px 12px;border-radius:999px;font-size:.88rem;color:#e6eef6}
.hero-cta{display:flex;gap:12px;flex-wrap:wrap}
.hero-media{position:relative;min-height:420px}
.hero-photo{margin:0;border-radius:14px;overflow:hidden;box-shadow:0 20px 50px rgba(0,0,0,.4);border:4px solid rgba(255,255,255,.9);background:#fff}
.hero-photo:first-child{width:72%;position:relative;z-index:2}
.hero-photo-2{position:absolute;right:0;bottom:-10px;width:52%;z-index:1;transform:rotate(3deg)}

/* sections */
.section{padding:84px 0}
.section-alt{background:var(--bg)}
.section-dark{background:var(--navy);color:#e6eef6}
.section-dark .eyebrow{color:#ffd56a}
.sec-head{max-width:760px;margin-bottom:36px}
.sec-head h2{font-size:clamp(1.6rem,3vw,2.2rem);font-weight:800;color:var(--navy)}
.section-dark .sec-head h2{color:#fff}
.sec-sub{color:var(--muted);margin:12px 0 0}

/* category cards */
.cat-tabs{display:grid;grid-template-columns:1fr 1fr;gap:18px;margin-bottom:56px}
.cat-tab{display:flex;gap:18px;align-items:center;padding:16px;border:1px solid var(--line);border-radius:var(--radius);text-decoration:none;color:var(--ink);background:#fff;box-shadow:var(--shadow);transition:.2s}
.cat-tab:hover{border-color:var(--steel);transform:translateY(-2px)}
.cat-tab img,.cat-tab-ph{width:96px;height:96px;object-fit:cover;border-radius:8px;flex:none;background:var(--bg)}
.cat-tab-ph{display:grid;place-items:center}
.cat-tab-ph svg{width:56px;fill:#fff;stroke:var(--steel);stroke-width:2}
.cat-tab h3{font-size:1.1rem;color:var(--navy)}
.cat-tab p{margin:4px 0 0;color:var(--muted);font-size:.92rem}

.sub-block{margin-bottom:64px}
.block-title{font-size:1.35rem;color:var(--navy);margin-bottom:18px;padding-left:12px;border-left:4px solid var(--accent)}

/* spec table */
.table-scroll{overflow-x:auto;border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);-webkit-overflow-scrolling:touch}
.spec-table{width:100%;border-collapse:collapse;min-width:760px;font-size:.95rem;background:#fff}
.spec-table th,.spec-table td{padding:12px 14px;border-bottom:1px solid var(--line);text-align:center;vertical-align:middle}
.spec-table thead tr:first-child th{background:var(--navy);color:#fff;font-size:1.05rem;letter-spacing:.04em}
.spec-table thead tr.sub th,.spec-table thead tr.sub td{background:var(--navy-2);color:#c7d5e3;font-size:.88rem;font-family:ui-monospace,Menlo,Consolas,monospace}
.spec-table tbody th{background:var(--bg);color:var(--navy);text-align:left;white-space:nowrap;width:120px;font-weight:700}
.spec-table thead th:first-child{text-align:left}
.spec-table tbody tr:hover td{background:#fbfcfe}
.spec-table tr.common td{color:var(--muted);background:#fcfdfe}
.spec-table tr:last-child th,.spec-table tr:last-child td{border-bottom:0}
.sw{display:inline-block;width:14px;height:14px;border-radius:3px;margin-right:6px;vertical-align:-2px;border:1px solid #b9c3cd;background-image:repeating-linear-gradient(45deg,rgba(0,0,0,.18) 0 2px,transparent 2px 5px)}
.sw-white{background-color:#fff}.sw-cream{background-color:#f3ead2}.sw-yellow{background-color:#e6d21f}.sw-black{background-color:#222}.sw-blue{background-color:#2f74d0}
.note{color:var(--muted);font-size:.88rem;margin:12px 0 0}

/* picker */
.picker{margin-top:40px;background:linear-gradient(180deg,#f7fafc,#eef3f8);border:1px solid var(--line);border-radius:16px;padding:28px;display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1.1fr);gap:28px}
.picker-head{grid-column:1/-1}
.picker-head h3{font-size:1.3rem;color:var(--navy)}
.picker-head p{margin:4px 0 0;color:var(--muted);font-size:.92rem}
.picker-form fieldset{border:0;padding:0;margin:0 0 18px}
.picker-form legend{font-weight:700;color:var(--navy);margin-bottom:8px;font-size:.95rem}
.picker-form output{color:var(--accent-d)}
.chips{display:flex;flex-wrap:wrap;gap:8px}
.chip{font-family:inherit;font-size:.92rem;padding:7px 14px;border-radius:999px;border:1px solid #c9d3de;background:#fff;color:var(--ink);cursor:pointer;transition:.15s}
.chip:hover{border-color:var(--steel)}
.chip.is-on{background:var(--navy);color:#fff;border-color:var(--navy)}
input[type=range]{width:100%;accent-color:var(--accent)}
.range-scale{display:flex;justify-content:space-between;font-size:.78rem;color:var(--muted)}
.picker-results{display:flex;flex-direction:column;gap:10px}
.series{display:flex;gap:14px;align-items:center;background:#fff;border:1px solid var(--line);border-radius:10px;padding:12px 14px;transition:.2s}
.series.is-off{display:none}
.series-net{width:14px;align-self:stretch;border-radius:4px;border:1px solid #b9c3cd;background-image:repeating-linear-gradient(45deg,rgba(0,0,0,.2) 0 2px,transparent 2px 5px);flex:none}
.series h4{font-size:1.02rem;color:var(--navy)}
.series h4 small{font-weight:500;color:var(--muted);font-family:ui-monospace,Menlo,Consolas,monospace;margin-left:6px}
.series p{margin:2px 0 0;font-size:.88rem;color:var(--muted)}
.picker-empty{background:#fff7e3;border:1px dashed var(--accent);padding:12px 14px;border-radius:10px;margin:0}

/* TOC */
.toc-box{margin-top:28px;border-radius:14px;padding:24px 28px;background:var(--navy);color:#dbe6f0;position:relative;overflow:hidden}
.toc-box::before{content:"TOC";position:absolute;right:18px;top:-10px;font-size:5.5rem;font-weight:900;color:rgba(255,255,255,.05)}
.toc-box h3{color:#fff;font-size:1.2rem;margin-bottom:10px}
.toc-box ul{margin:0;padding-left:1.2em}
.toc-box li{margin:6px 0}
.toc-box strong{color:#ffd56a}
.toc-box .note{color:#9fb3c8}

/* cotton */
.cotton{display:grid;grid-template-columns:.8fr 1.2fr;gap:40px;align-items:center;background:var(--bg);border-radius:16px;padding:32px;margin-bottom:0}
.photo-placeholder{aspect-ratio:3/4;max-height:420px;margin:0 auto;border:2px dashed #b9c6d3;border-radius:14px;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:12px;color:var(--muted);background:#fff;text-align:center;padding:20px}
.photo-placeholder svg{width:90px;fill:#f5f1e6;stroke:#9fb0c1;stroke-width:2}
.cotton-copy p{margin:0 0 14px}
.ticks{list-style:none;padding:0;margin:0 0 18px}
.ticks li{padding-left:28px;position:relative;margin:6px 0}
.ticks li::before{content:"✓";position:absolute;left:0;top:0;width:20px;height:20px;border-radius:50%;background:var(--teal);color:#fff;font-size:.75rem;display:grid;place-items:center;margin-top:3px}
.todo-box{border:1px dashed var(--accent);background:#fffaf0;border-radius:10px;padding:12px 16px;margin-bottom:20px;display:flex;flex-direction:column;gap:2px;font-size:.92rem}
.todo-box a{font-weight:700;word-break:break-all}

/* structure */
.structure{display:grid;grid-template-columns:300px 1fr;gap:56px;align-items:start}
.structure-fig{margin:0;background:#fff;border-radius:16px;padding:24px;box-shadow:var(--shadow);position:sticky;top:90px}
.structure-fig img{max-height:620px;margin:0 auto;width:auto}
.layers{list-style:none;padding:0;margin:0 0 26px;display:grid;grid-template-columns:1fr 1fr;gap:10px}
.layers li{display:flex;align-items:center;gap:12px;background:#fff;border:1px solid var(--line);border-radius:10px;padding:12px 14px}
.layers b{flex:none;width:32px;height:32px;border-radius:50%;background:var(--navy);color:#fff;display:grid;place-items:center;font-size:.95rem}
.layers li:nth-child(4) b{background:#111}
.layers li:nth-child(4){border-color:#333}
.kv{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin:0 0 30px}
.kv div{background:#fff;border-radius:10px;padding:12px 14px;border-top:3px solid var(--accent)}
.kv .wide{grid-column:1/-1}
.kv dt{font-size:.82rem;color:var(--muted)}
.kv dd{margin:2px 0 0;font-weight:800;color:var(--navy);font-size:1.08rem}
.principle h3{font-size:1.2rem;color:var(--navy);margin-bottom:8px}
.principle p{margin:0 0 16px;color:var(--muted)}
.flow{display:grid;grid-template-columns:repeat(3,1fr);gap:0;border-radius:12px;overflow:hidden;border:1px solid var(--line)}
.flow div{padding:16px;background:#fff;position:relative;display:flex;flex-direction:column;gap:4px}
.flow div+div{border-left:1px solid var(--line)}
.flow b{color:var(--steel)}
.flow span{font-size:.92rem}
.flow div:nth-child(2){background:#eef3f8}

/* applications */
.apps{list-style:none;padding:0;margin:0 0 40px;display:grid;grid-template-columns:repeat(4,1fr);gap:14px}
.apps li{background:#fff;border:1px solid var(--line);border-radius:12px;padding:20px 18px;font-weight:600;color:var(--navy);box-shadow:var(--shadow);display:flex;flex-direction:column;gap:8px}
.apps i{font-style:normal;font-weight:900;color:var(--accent);font-size:1.3rem;font-family:ui-monospace,Menlo,Consolas,monospace}
.lines h3{font-size:1.15rem;color:var(--navy);margin-bottom:12px}
.line-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:12px}
.line-grid div{background:var(--bg);border-radius:10px;padding:16px;display:flex;flex-direction:column}
.line-grid strong{color:var(--navy)}
.line-grid span{color:var(--muted);font-size:.92rem}

/* effect */
.effect{display:grid;grid-template-columns:1fr 300px;gap:24px;align-items:start}
.effect-photos{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.effect figure,.site-photos figure{margin:0;background:#0a1a2b;border-radius:12px;overflow:hidden;border:1px solid rgba(255,255,255,.1)}
.effect img{width:100%;aspect-ratio:4/3;object-fit:cover}
figcaption{padding:10px 14px;font-size:.9rem;color:#c7d5e3}
.conditions{background:var(--accent);color:#1b1300;border-radius:12px;padding:22px}
.conditions h3{font-size:1.15rem;margin-bottom:10px}
.conditions dl{margin:0}
.conditions div{padding:10px 0;border-top:1px solid rgba(0,0,0,.15)}
.conditions dt{font-size:.82rem;opacity:.75}
.conditions dd{margin:0;font-weight:800;font-size:1.05rem}
.site-photos{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-top:24px}
.site-photos img{width:100%;aspect-ratio:4/5;object-fit:cover;object-position:center 40%}

/* contact */
.contact{display:grid;grid-template-columns:1fr 1.1fr;gap:48px;align-items:start}
.contact h2{font-size:clamp(1.4rem,2.6vw,2rem);color:var(--navy);font-weight:800}
.phone-card{display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:14px;margin-top:14px;padding:16px 18px;border-radius:12px;background:var(--navy);color:#fff;text-decoration:none;transition:.2s}
.phone-card:hover{background:var(--navy-2)}
.pc-label{font-size:.8rem;background:rgba(255,255,255,.12);padding:3px 8px;border-radius:6px;color:#c7d5e3}
.pc-num{font-size:1.35rem;font-weight:800;letter-spacing:.03em;min-width:0;overflow-wrap:anywhere}
.pc-mail{font-size:1.05rem;letter-spacing:0}
.pc-act{font-size:.85rem;color:var(--accent);font-weight:700;white-space:nowrap}
.inquiry{background:#fff;border:1px solid var(--line);border-radius:16px;padding:28px;box-shadow:var(--shadow)}
.inquiry h3{font-size:1.25rem;color:var(--navy)}
.form-hint{color:var(--muted);font-size:.86rem;margin:4px 0 16px;overflow-wrap:anywhere}
.inquiry label{display:block;font-size:.9rem;font-weight:600;color:var(--navy);margin-bottom:12px}
.inquiry input,.inquiry select,.inquiry textarea{display:block;width:100%;margin-top:6px;padding:11px 12px;border:1px solid #c9d3de;border-radius:8px;font:inherit;font-weight:400;color:var(--ink);background:#fbfcfd}
.inquiry input:focus,.inquiry select:focus,.inquiry textarea:focus{outline:2px solid rgba(240,164,0,.45);border-color:var(--accent)}
.row2{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.inquiry-result{margin-top:16px;border-top:1px dashed var(--line);padding-top:16px}
.inquiry-result pre{white-space:pre-wrap;font-family:inherit;background:var(--bg);padding:12px;border-radius:8px;margin:0 0 12px;font-size:.9rem}
.inq-actions{display:flex;flex-wrap:wrap;gap:10px}

/* footer */
.footer{background:#08131f;color:#9fb3c8;padding:40px 0 90px;font-size:.92rem}
.footer-inner{display:flex;justify-content:space-between;gap:30px;flex-wrap:wrap}
.footer strong{color:#fff}
.footer p{margin:4px 0}
.footer a{color:#d6e2ee}
.footer-nav{display:flex;flex-wrap:wrap;gap:6px 18px;align-content:flex-start}
.footer-nav a{text-decoration:none}
.copy{text-align:center;margin:30px 0 0;font-size:.82rem;color:#6d8296}
.float-call{display:none}

/* responsive */
@media (max-width:1000px){
  .hero-inner{grid-template-columns:1fr;padding-top:48px}
  .hero-media{min-height:0;max-width:440px;margin:0 auto;width:100%}
  .structure{grid-template-columns:220px 1fr;gap:32px}
  .apps{grid-template-columns:repeat(2,1fr)}
  .effect{grid-template-columns:1fr}
  .kv{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:860px){
  .nav-toggle{display:block}
  .nav{position:absolute;top:64px;left:0;right:0;background:var(--navy);flex-direction:column;align-items:stretch;padding:8px 16px 16px;display:none;box-shadow:0 10px 20px rgba(0,0,0,.25)}
  .nav.is-open{display:flex}
  .nav a{padding:12px;border-bottom:1px solid rgba(255,255,255,.06)}
  .nav .nav-call{margin:10px 0 0;text-align:center}
  .picker{grid-template-columns:1fr;padding:20px}
  .contact{grid-template-columns:1fr;gap:32px}
  .cotton{grid-template-columns:1fr;padding:22px}
  .photo-placeholder{max-height:260px;aspect-ratio:auto;height:240px;width:100%}
}
@media (max-width:640px){
  .section{padding:56px 0}
  .wrap{padding:0 16px}
  .cat-tabs{grid-template-columns:1fr}
  .cat-tab img,.cat-tab-ph{width:72px;height:72px}
  .structure{grid-template-columns:1fr}
  .structure-fig{position:static;max-width:220px;margin:0 auto;padding:14px}
  .structure-fig img{max-height:420px}
  .layers{grid-template-columns:1fr}
  .flow{grid-template-columns:1fr}
  .flow div+div{border-left:0;border-top:1px solid var(--line)}
  .apps{grid-template-columns:1fr 1fr;gap:10px}
  .apps li{padding:14px;font-size:.92rem}
  .line-grid{grid-template-columns:1fr 1fr}
  .effect-photos{grid-template-columns:1fr}
  .site-photos{grid-template-columns:repeat(3,1fr);gap:8px}
  .site-photos figcaption{font-size:.75rem;padding:6px 8px}
  .row2{grid-template-columns:1fr;gap:0}
  .inquiry{padding:20px}
  .phone-card{grid-template-columns:auto 1fr;}
  .phone-card .pc-act{grid-column:1/-1}
  .hero-photo-2{bottom:-6px}
  .float-call{display:flex;position:fixed;left:16px;right:16px;bottom:14px;z-index:60;justify-content:center;padding:14px;border-radius:12px;background:var(--accent);color:#1b1300;font-weight:800;text-decoration:none;box-shadow:0 10px 30px rgba(0,0,0,.3)}
}

/* fixes after review */
.spec-table{table-layout:fixed}
.spec-table thead th:first-child,.spec-table tbody th{width:130px}
.swipe-hint{display:none;font-size:.82rem;color:var(--muted);margin:0 0 8px;text-align:right}
.ask-list{margin-top:24px;background:var(--bg);border-radius:12px;padding:18px 20px}
.ask-list h3{font-size:1rem;color:var(--navy);margin-bottom:8px}
.ask-list ul{margin:0;padding-left:1.2em;color:var(--muted);font-size:.93rem}
.footer{padding-bottom:30px}
.float-call{opacity:0;pointer-events:none;transform:translateY(20px);transition:.25s}
.float-call.is-shown{opacity:1;pointer-events:auto;transform:none}
@media (max-width:640px){
  .footer{padding-bottom:90px}
  .swipe-hint{display:block}
  .spec-table{min-width:640px;font-size:.88rem}
  .spec-table th,.spec-table td{padding:10px 8px}
  .spec-table thead th:first-child,.spec-table tbody th,.spec-table thead tr.sub th{position:sticky;left:0;z-index:1;width:92px;box-shadow:2px 0 4px rgba(0,0,0,.06)}
  .spec-table thead tr:first-child th:first-child{background:var(--navy)}
  .spec-table tr.common td{text-align:left;padding-left:14px}
  .hero-media{max-width:330px}
}

/* cotton photo + specs */
.cotton-photo{margin:0;background:#fff;border-radius:14px;overflow:hidden;box-shadow:var(--shadow);max-width:380px;margin:0 auto}
.cotton-photo img{width:100%;aspect-ratio:3/4;object-fit:cover}
.cotton-photo figcaption{color:var(--muted);text-align:center;font-size:.85rem;padding:8px 12px;border-top:1px solid var(--line)}
.cotton-specs{display:grid;grid-template-columns:auto 1fr;margin:0 0 16px;border:1px solid var(--line);border-radius:10px;overflow:hidden;background:#fff}
.cotton-specs div{display:contents}
.cotton-specs dt{background:var(--navy);color:#fff;font-weight:700;padding:10px 16px;font-size:.92rem}
.cotton-specs dd{margin:0;padding:10px 16px;font-weight:600;color:var(--navy)}
.cotton-specs div+div dt,.cotton-specs div+div dd{border-top:1px solid var(--line)}
.cotton-specs div+div dt{border-top-color:rgba(255,255,255,.12)}
.cotton-specs div+div dd{font-weight:400;color:var(--muted)}
@media (max-width:860px){.cotton-photo{max-width:300px}}

/* cotton gallery */
.cotton-photo{background:#fff}
.cotton-main{display:block;cursor:zoom-in}
.cotton-photo img{aspect-ratio:4/5;object-fit:contain;background:#fff}
.cotton-thumbs{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;max-width:380px;margin:12px auto 0}
.cotton-thumbs button{padding:0;border:2px solid var(--line);border-radius:10px;overflow:hidden;background:#fff;cursor:pointer;transition:.15s}
.cotton-thumbs button:hover{border-color:var(--steel)}
.cotton-thumbs button.is-on{border-color:var(--accent)}
.cotton-thumbs img{width:100%;aspect-ratio:4/5;object-fit:contain}
.lightbox{position:fixed;inset:0;z-index:100;background:rgba(5,12,20,.88);display:flex;align-items:center;justify-content:center;padding:24px}
.lightbox[hidden]{display:none}
.lightbox img{max-width:min(92vw,720px);max-height:88vh;border-radius:10px;background:#fff}
.lb-close{position:absolute;top:14px;right:18px;font-size:2rem;line-height:1;color:#fff;background:none;border:0;cursor:pointer}
@media (max-width:860px){.cotton-thumbs{max-width:300px}}

/* language switch (中文 / EN) */
.nav{margin-left:auto}
.lang-switch{display:flex;flex:none;margin-left:12px;padding:2px;border:1px solid rgba(255,255,255,.28);border-radius:999px}
.lang-switch button{font-family:inherit;font-size:.8rem;font-weight:700;line-height:1.4;color:#d6e2ee;background:none;border:0;padding:4px 10px;border-radius:999px;cursor:pointer;transition:.15s}
.lang-switch button:hover{color:#fff}
.lang-switch button.is-on{background:#fff;color:var(--navy)}
@media (max-width:860px){
  .nav{margin-left:0}
  .lang-switch{order:2;margin-left:auto;margin-right:6px}
  .nav-toggle{order:3}
}

/* English layout tweaks (longer text); Chinese layout unchanged */
.footer .alt-name{display:block;font-weight:400;font-size:.85rem;color:#9fb3c8;margin-top:2px}
html.lang-en .hero h1{font-size:clamp(1.75rem,3.4vw,2.5rem)}
html.lang-en .nav a{padding:8px 10px}
html.lang-en .spec-table thead th:first-child,html.lang-en .spec-table tbody th{width:165px;white-space:normal}
html.lang-en .spec-table td{overflow-wrap:break-word}
html.lang-en .pc-mail.pc-num{font-size:1rem}
@media (max-width:1100px) and (min-width:861px){
  html.lang-en .brand-text small{display:none}
  html.lang-en .nav a{padding:8px 7px;font-size:.88rem}
  html.lang-en .nav .nav-call{margin-left:4px}
}
@media (max-width:640px){
  html.lang-en .spec-table{min-width:720px}
  html.lang-en .spec-table thead th:first-child,html.lang-en .spec-table tbody th,html.lang-en .spec-table thead tr.sub th{width:104px}
}
@media (max-width:420px){
  html.lang-en .brand{gap:8px}
  html.lang-en .brand-mark img{height:32px}
  html.lang-en .brand-text strong{font-size:.92rem;letter-spacing:0}
  html.lang-en .brand-text small{font-size:.66rem}
  .lang-switch button{padding:4px 8px}
}
.nw{white-space:nowrap}

/* hero flip rotation: same layout, images swap with a flip */
.hero-photo{perspective:1200px}
.hero-photo:first-child{aspect-ratio:360/490}
.hero-photo-2{aspect-ratio:396/446}
.hero-photo img{width:100%;height:100%;object-fit:cover;display:block;background:#fff;transition:transform .45s ease-in;backface-visibility:hidden}
.hero-photo img.fit-contain{object-fit:contain;padding:5%}
.hero-photo img.flip-out{transform:rotateY(90deg)}
.hero-photo img.flip-in{transform:rotateY(-90deg);transition:none}
@media (prefers-reduced-motion:reduce){.hero-photo img{transition:none}}
.hero-src{display:none!important}