/* TAILNTAIL (TNT PET) — Product Detail Pages
   Design tokens aligned with tntpet.com */
:root{
  --ink:#1a1a1a; --ink-2:#3f3f3f; --ink-3:#666666;
  --line:#eaeaea; --line-2:#e5e5e5;
  --card:#f5f5f5; --blue:#4169e1; --blue-d:#3558c4;
  --navy:#0b1220; --navy-2:#111c30;
  --max:1200px;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"PingFang SC","Microsoft YaHei",sans-serif;
  color:var(--ink);background:#fff;line-height:1.7;font-size:16px;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
ul{list-style:none}
.wrap{max-width:var(--max);margin:0 auto;padding:0 24px}

/* ---------- Header ---------- */
.site-header{position:fixed;top:0;left:0;right:0;z-index:1000;background:var(--navy);transition:background .3s ease,box-shadow .3s ease}
.site-header .wrap{max-width:1520px;display:flex;align-items:center;justify-content:space-between;height:72px;position:relative}
.header-nav{display:flex;align-items:center;gap:28px}
.header-nav a{color:#fff;font-size:15px;letter-spacing:.5px;opacity:.92;transition:opacity .2s}
.header-nav a:hover,.header-nav a.active{opacity:1}
.header-nav a.active{border-bottom:1px solid #fff;padding-bottom:2px}
.header-logo{position:absolute;left:50%;transform:translateX(-50%);color:#fff;
  font-size:22px;font-weight:300;letter-spacing:10px;text-indent:10px;white-space:nowrap}
.header-lang{color:#fff;font-size:14px;border:1px solid rgba(255,255,255,.35);border-radius:999px;
  padding:6px 18px;background:rgba(255,255,255,.08);backdrop-filter:blur(8px)}
@media(max-width:900px){
  .header-nav{gap:16px}.header-nav a{font-size:13px}
  .header-logo{font-size:16px;letter-spacing:6px}
}

/* ---------- Breadcrumb ---------- */
.breadcrumb{padding:104px 0 0;font-size:13.5px;color:var(--ink-3)}
.breadcrumb a{color:var(--ink-3)}.breadcrumb a:hover{color:var(--ink)}
.breadcrumb span{margin:0 8px;color:#bbb}

/* ---------- Hero ---------- */
.phero{margin:20px 0 72px;background:var(--card);border-radius:20px;overflow:hidden;
  display:grid;grid-template-columns:1fr 1.05fr}
.phero-media{display:flex;align-items:center;justify-content:center;padding:48px;background:#efefef}
.phero-media img{border-radius:12px;max-height:460px;object-fit:contain}
.phero-body{padding:56px 56px 56px 8px;display:flex;flex-direction:column;justify-content:center}
.phero-kicker{font-size:13px;letter-spacing:3px;text-transform:uppercase;color:var(--ink-3);margin-bottom:14px}
.phero h1{font-size:34px;line-height:1.25;font-weight:600;letter-spacing:.5px;margin-bottom:6px}
.phero-model{font-size:15px;color:var(--ink-3);letter-spacing:2px;margin-bottom:22px;font-weight:500}
.phero-lede{color:var(--ink-2);font-size:16.5px;margin-bottom:26px}
.phero-chips{display:flex;flex-wrap:wrap;gap:10px;margin-bottom:32px}
.phero-chips li{font-size:13.5px;color:var(--ink-2);background:#fff;border:1px solid var(--line-2);
  border-radius:999px;padding:7px 16px}
.phero-cta{display:flex;gap:14px;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;gap:8px;border-radius:999px;padding:13px 28px;
  font-size:15px;font-weight:500;transition:all .2s ease;cursor:pointer;border:none}
.btn-primary{background:var(--blue);color:#fff}
.btn-primary:hover{background:var(--blue-d);transform:translateY(-1px)}
.btn-ghost{background:transparent;color:var(--ink);border:1px solid var(--ink)}
.btn-ghost:hover{background:var(--ink);color:#fff}
.btn .arr{font-size:17px;line-height:1}
@media(max-width:900px){
  .phero{grid-template-columns:1fr}
  .phero-body{padding:32px 28px 40px}
  .phero h1{font-size:26px}
  .phero-media{padding:28px}
}

/* ---------- Sections ---------- */
.section{padding:72px 0}
.section + .section{border-top:1px solid var(--line)}
.sec-head{max-width:760px;margin-bottom:44px}
.sec-label{font-size:13px;letter-spacing:4px;text-transform:uppercase;color:var(--blue);font-weight:600;margin-bottom:12px}
.sec-title{font-size:30px;font-weight:600;line-height:1.3;letter-spacing:.3px}
.sec-sub{color:var(--ink-3);margin-top:14px;font-size:16px}
@media(max-width:700px){.sec-title{font-size:24px}.section{padding:52px 0}}

/* Why / narrative */
.why-grid{display:grid;grid-template-columns:300px 1fr;gap:56px}
.why-grid .sec-head{margin-bottom:0;position:sticky;top:110px;align-self:start}
.why-body p{color:var(--ink-2);margin-bottom:20px;font-size:16.5px}
.why-body strong{color:var(--ink)}
@media(max-width:900px){.why-grid{grid-template-columns:1fr;gap:28px}.why-grid .sec-head{position:static}}

/* Feature grid */
.feat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.feat-card{background:var(--card);border-radius:16px;padding:30px 26px;transition:transform .25s ease,box-shadow .25s ease}
.feat-card:hover{transform:translateY(-4px);box-shadow:0 14px 30px -18px rgba(0,0,0,.25)}
.feat-card img{width:34px;height:34px;object-fit:contain;margin-bottom:18px}
.feat-card h3{font-size:16.5px;font-weight:600;margin-bottom:10px;line-height:1.4}
.feat-card p{font-size:14px;color:var(--ink-3);line-height:1.65}
@media(max-width:1000px){.feat-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:560px){.feat-grid{grid-template-columns:1fr}}

/* Deep dive rows */
.deep-row{display:grid;grid-template-columns:1fr 1fr;gap:56px;align-items:center;margin-bottom:64px}
.deep-row:last-child{margin-bottom:0}
.deep-row.flip .deep-media{order:2}
.deep-media{background:var(--card);border-radius:18px;padding:36px;display:flex;align-items:center;justify-content:center}
.deep-media img{border-radius:12px;max-height:380px;object-fit:contain}
.deep-body .num{font-size:13px;letter-spacing:3px;color:var(--blue);font-weight:600;margin-bottom:10px}
.deep-body h3{font-size:23px;font-weight:600;margin-bottom:14px;line-height:1.35}
.deep-body p{color:var(--ink-2);font-size:15.5px;margin-bottom:12px}
.deep-list{margin-top:14px}
.deep-list li{position:relative;padding-left:22px;color:var(--ink-2);font-size:15px;margin-bottom:9px}
.deep-list li:before{content:"";position:absolute;left:0;top:11px;width:10px;height:2px;background:var(--blue)}
@media(max-width:900px){.deep-row{grid-template-columns:1fr;gap:26px}.deep-row.flip .deep-media{order:0}}

/* Spec table */
.spec-table{width:100%;border-collapse:collapse;background:#fff;border-radius:14px;overflow:hidden;
  box-shadow:0 0 0 1px var(--line)}
.spec-table th,.spec-table td{text-align:left;padding:15px 22px;font-size:15px;border-bottom:1px solid var(--line)}
.spec-table th{width:260px;color:var(--ink-3);font-weight:500;background:#fafafa;vertical-align:top}
.spec-table td{color:var(--ink);font-weight:500}
.spec-table tr:last-child th,.spec-table tr:last-child td{border-bottom:none}
@media(max-width:640px){.spec-table th{width:130px}.spec-table th,.spec-table td{padding:12px 14px;font-size:14px}}

/* OEM band */
.oem{background:var(--navy);color:#fff;border-radius:22px;padding:64px 56px;
  display:grid;grid-template-columns:1.2fr 1fr;gap:48px;align-items:center}
.oem h2{font-size:28px;font-weight:600;line-height:1.35;margin-bottom:16px}
.oem p{color:rgba(255,255,255,.75);font-size:15.5px;margin-bottom:26px}
.oem-list{display:grid;grid-template-columns:1fr 1fr;gap:14px 24px}
.oem-list li{position:relative;padding-left:26px;font-size:14.5px;color:rgba(255,255,255,.88)}
.oem-list li:before{content:"";position:absolute;left:0;top:9px;width:14px;height:14px;border-radius:50%;
  background:var(--blue);box-shadow:inset 0 0 0 3px var(--navy)}
@media(max-width:900px){.oem{grid-template-columns:1fr;padding:44px 30px}.oem-list{grid-template-columns:1fr}}

/* FAQ */
.faq-item{border:1px solid var(--line);border-radius:14px;margin-bottom:14px;background:#fff;overflow:hidden}
.faq-item summary{cursor:pointer;list-style:none;padding:20px 26px;font-size:16px;font-weight:600;
  display:flex;justify-content:space-between;align-items:center;gap:16px}
.faq-item summary::-webkit-details-marker{display:none}
.faq-item summary:after{content:"+";font-size:22px;font-weight:300;color:var(--ink-3);flex-shrink:0;transition:transform .2s}
.faq-item[open] summary:after{transform:rotate(45deg)}
.faq-item .faq-a{padding:0 26px 22px;color:var(--ink-2);font-size:15px;line-height:1.75}

/* Related */
.rel-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.rel-card{background:var(--card);border-radius:16px;overflow:hidden;transition:transform .25s ease,box-shadow .25s ease;display:block}
.rel-card:hover{transform:translateY(-4px);box-shadow:0 14px 30px -18px rgba(0,0,0,.25)}
.rel-card .rel-img{background:#efefef;padding:26px;display:flex;align-items:center;justify-content:center;height:190px}
.rel-card img{max-height:150px;object-fit:contain}
.rel-card .rel-body{padding:18px 20px 22px}
.rel-card h3{font-size:15px;font-weight:600;line-height:1.45;margin-bottom:4px}
.rel-card span{font-size:12.5px;color:var(--ink-3);letter-spacing:1.5px}
@media(max-width:1000px){.rel-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:560px){.rel-grid{grid-template-columns:1fr}}

/* CTA band */
.cta-band{background:linear-gradient(135deg,var(--navy) 0%,var(--navy-2) 60%,#1b2c4d 100%);
  border-radius:22px;padding:60px 56px;text-align:center;color:#fff}
.cta-band h2{font-size:28px;font-weight:600;margin-bottom:14px;letter-spacing:.3px}
.cta-band p{color:rgba(255,255,255,.72);max-width:560px;margin:0 auto 30px;font-size:15.5px}
@media(max-width:700px){.cta-band{padding:44px 26px}.cta-band h2{font-size:22px}}

/* ---------- Footer ---------- */
.site-footer{margin-top:88px}
.footer-banner{background:var(--navy);height:170px;display:flex;align-items:center;justify-content:center}
.footer-banner span{color:rgba(255,255,255,.8);font-size:20px;letter-spacing:8px;font-weight:300;text-transform:uppercase}
.footer-main{background:#fff;padding:60px 0 40px;border-top:1px solid var(--line)}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:36px}
.footer-brand{color:var(--ink);font-size:20px;letter-spacing:6px;font-weight:300;margin-bottom:14px}
.footer-col h4{font-size:15px;font-weight:600;margin-bottom:16px;color:var(--ink)}
.footer-col li{margin-bottom:9px}
.footer-col a,.footer-col p{font-size:13.5px;color:var(--ink-3);line-height:1.7}
.footer-col a:hover{color:var(--ink)}
.footer-bottom{border-top:1px solid var(--line);margin-top:40px;padding-top:22px;
  font-size:12.5px;color:#999;display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap}
@media(max-width:900px){.footer-grid{grid-template-columns:1fr 1fr}}
@media(max-width:560px){.footer-grid{grid-template-columns:1fr}}

/* Deep cards (no-gallery variant) */
.deep-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.deep-card{background:var(--card);border-radius:18px;padding:34px 30px}
.deep-card .num{font-size:13px;letter-spacing:3px;color:var(--blue);font-weight:600;margin-bottom:12px}
.deep-card h3{font-size:19px;font-weight:600;margin-bottom:14px;line-height:1.4}
.deep-card p{color:var(--ink-2);font-size:14.5px;margin-bottom:12px}
.deep-card .deep-list li{font-size:14px}
@media(max-width:900px){.deep-cards{grid-template-columns:1fr}}

/* Compare table */
.cmp-wrap{overflow-x:auto;border-radius:14px;box-shadow:0 0 0 1px var(--line)}
.cmp-table{width:100%;min-width:900px;border-collapse:collapse;background:#fff}
.cmp-table th,.cmp-table td{text-align:left;padding:15px 18px;font-size:14px;border-bottom:1px solid var(--line);vertical-align:top}
.cmp-table thead th{background:#fafafa;color:var(--ink-3);font-weight:600;font-size:13px;letter-spacing:.5px;white-space:nowrap}
.cmp-table tbody tr:last-child td{border-bottom:none}
.cmp-table tbody tr:hover{background:#fafafa}
.cmp-table td a{color:var(--blue)}
.cmp-table td a:hover{text-decoration:underline}