/* =========================================================================
   BTX Sciences — Design System
   Premium scientific aesthetic: deep navy + electric cyan molecular look.
   All colors are CSS variables so the owner can re-theme from Customizer.
   ========================================================================= */

:root{
  --btx-navy-900:#06101f;
  --btx-navy-800:#0a1834;
  --btx-navy-700:#0d2148;
  --btx-navy-600:#123063;
  --btx-blue:#1e7fff;        /* primary action / links */
  --btx-blue-dark:#155fd0;
  --btx-cyan:#22d3ee;        /* electric accent */
  --btx-ink:#16202e;         /* body text */
  --btx-muted:#5b6b7f;       /* secondary text */
  --btx-line:#e4e9f0;        /* hairlines */
  --btx-bg:#ffffff;
  --btx-bg-alt:#f6f9fc;      /* section tint */
  --btx-bg-tint:#eef4fb;
  --btx-success:#16a34a;
  --btx-warn:#d97706;
  --btx-radius:14px;
  --btx-radius-sm:8px;
  --btx-shadow:0 10px 30px rgba(11,31,58,.10);
  --btx-shadow-lg:0 24px 60px rgba(11,31,58,.18);
  --btx-maxw:1240px;
  --btx-font:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  --btx-serif:Georgia,"Times New Roman",serif;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  font-family:var(--btx-font);
  color:var(--btx-ink);
  background:var(--btx-bg);
  line-height:1.6;
  font-size:16px;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;height:auto;display:block}
a{color:var(--btx-blue);text-decoration:none;transition:color .15s ease}
a:hover{color:var(--btx-blue-dark)}
h1,h2,h3,h4{font-family:var(--btx-serif);color:var(--btx-navy-800);line-height:1.2;margin:0 0 .5em}
h1{font-size:clamp(2rem,4vw,3.2rem)}
h2{font-size:clamp(1.6rem,3vw,2.4rem)}
h3{font-size:1.3rem}
p{margin:0 0 1em}

.btx-container{max-width:var(--btx-maxw);margin:0 auto;padding:0 24px}
.btx-section{padding:72px 0}
.btx-section--tint{background:var(--btx-bg-alt)}
.btx-section__head{text-align:center;max-width:760px;margin:0 auto 48px}
.btx-section__eyebrow{display:inline-block;text-transform:uppercase;letter-spacing:.16em;font-size:.78rem;font-weight:700;color:var(--btx-blue);margin-bottom:12px}
.btx-section__head p{color:var(--btx-muted);font-size:1.08rem}

/* ---------- Buttons ---------- */
.btx-btn{
  display:inline-flex;align-items:center;gap:8px;
  padding:13px 26px;border-radius:999px;font-weight:600;font-size:.98rem;
  border:2px solid transparent;cursor:pointer;transition:all .18s ease;line-height:1;
}
.btx-btn--primary{background:var(--btx-blue);color:#fff}
.btx-btn--primary:hover{background:var(--btx-blue-dark);color:#fff;transform:translateY(-1px);box-shadow:var(--btx-shadow)}
.btx-btn--ghost{background:transparent;color:#fff;border-color:rgba(255,255,255,.5)}
.btx-btn--ghost:hover{background:rgba(255,255,255,.12);color:#fff}
.btx-btn--outline{background:#fff;color:var(--btx-blue);border-color:var(--btx-line)}
.btx-btn--outline:hover{border-color:var(--btx-blue)}
.btx-btn--block{width:100%;justify-content:center}

/* ============================ HEADER ============================ */
.btx-topbar{background:var(--btx-navy-900);color:#cfe0f5;font-size:.85rem}
.btx-topbar .btx-container{display:flex;justify-content:space-between;align-items:center;height:40px;gap:18px;flex-wrap:wrap}
.btx-topbar a{color:#cfe0f5}
.btx-topbar a:hover{color:#fff}
.btx-topbar__left{display:flex;gap:22px;align-items:center}
.btx-topbar__right{display:flex;gap:18px;align-items:center}
.btx-topbar__item{display:inline-flex;align-items:center;gap:7px}

.btx-header{position:sticky;top:0;z-index:50;background:#fff;border-bottom:1px solid var(--btx-line);box-shadow:0 2px 14px rgba(11,31,58,.05)}
.btx-header__bar{display:flex;align-items:center;gap:28px;height:84px}
.btx-logo{display:flex;align-items:center;gap:12px;flex-shrink:0}
.btx-logo__mark{width:46px;height:46px;flex:0 0 46px}
.btx-logo__text{font-family:var(--btx-serif);line-height:1.05}
.btx-logo__name{display:block;font-size:1.45rem;font-weight:700;color:var(--btx-navy-800);letter-spacing:.5px}
.btx-logo__tag{display:block;font-size:.66rem;letter-spacing:.22em;text-transform:uppercase;color:var(--btx-blue);font-family:var(--btx-font);font-weight:600}

.btx-search{flex:1;max-width:520px;margin:0 auto}
.btx-search form{display:flex;border:1.5px solid var(--btx-line);border-radius:999px;overflow:hidden;background:#fff}
.btx-search input[type=search]{flex:1;border:0;padding:11px 18px;font-size:.95rem;outline:none;background:transparent}
.btx-search button{border:0;background:var(--btx-blue);color:#fff;padding:0 22px;font-weight:600;cursor:pointer}
.btx-search button:hover{background:var(--btx-blue-dark)}

.btx-header__actions{display:flex;align-items:center;gap:20px;flex-shrink:0}
.btx-header__link{display:inline-flex;align-items:center;gap:7px;font-size:.92rem;font-weight:600;color:var(--btx-navy-800)}
.btx-cart-count{background:var(--btx-blue);color:#fff;border-radius:999px;font-size:.72rem;min-width:20px;height:20px;display:inline-flex;align-items:center;justify-content:center;padding:0 6px}

/* primary nav */
.btx-nav{background:var(--btx-navy-800)}
.btx-nav .btx-container{display:flex;align-items:center}
.btx-menu{list-style:none;margin:0;padding:0;display:flex;flex-wrap:wrap}
.btx-menu li{position:relative}
.btx-menu a{display:block;color:#dce7f7;padding:14px 17px;font-size:.92rem;font-weight:600;letter-spacing:.01em}
.btx-menu a:hover,.btx-menu .current-menu-item>a{color:#fff;background:var(--btx-navy-700)}
.btx-menu .sub-menu{position:absolute;top:100%;left:0;min-width:240px;background:#fff;box-shadow:var(--btx-shadow-lg);border-radius:0 0 var(--btx-radius-sm) var(--btx-radius-sm);padding:8px 0;display:none;z-index:60}
.btx-menu li:hover>.sub-menu,.btx-menu li:focus-within>.sub-menu{display:block}
.btx-menu .sub-menu a{color:var(--btx-ink);padding:10px 18px;font-weight:500}
.btx-menu .sub-menu a:hover{background:var(--btx-bg-tint);color:var(--btx-blue)}
/* dropdown caret on parent items */
.btx-menu .menu-item-has-children>a::after{content:"";display:inline-block;margin-left:7px;vertical-align:middle;
  border:4px solid transparent;border-top-color:currentColor;border-bottom:0;position:relative;top:1px;transition:transform .2s}
.btx-menu .menu-item-has-children:hover>a::after{transform:rotate(180deg)}

/* product-family ribbon */
.btx-families{background:var(--btx-navy-700);border-top:1px solid rgba(255,255,255,.06)}
.btx-families .btx-container{display:flex;flex-wrap:wrap;gap:4px;align-items:center}
.btx-families__label{color:var(--btx-cyan);font-size:.74rem;font-weight:700;text-transform:uppercase;letter-spacing:.14em;margin-right:8px}
.btx-families a{color:#bcd2ee;font-size:.84rem;padding:9px 12px;border-radius:6px}
.btx-families a:hover{color:#fff;background:rgba(255,255,255,.08)}

/* mobile toggle */
.btx-burger{display:none;background:none;border:0;cursor:pointer;flex-direction:column;gap:5px;padding:8px}
.btx-burger span{width:24px;height:2px;background:var(--btx-navy-800);display:block}

/* ============================ HERO ============================ */
.btx-hero{position:relative;background:
   radial-gradient(1200px 600px at 80% -10%,rgba(34,211,238,.18),transparent 60%),
   radial-gradient(900px 500px at 0% 110%,rgba(30,127,255,.22),transparent 55%),
   linear-gradient(135deg,var(--btx-navy-900),var(--btx-navy-700));
  color:#fff;overflow:hidden}
.btx-hero::before{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:46px 46px;mask-image:radial-gradient(70% 70% at 60% 30%,#000,transparent);opacity:.6}
.btx-hero__inner{position:relative;display:grid;grid-template-columns:1.05fr .95fr;gap:48px;align-items:center;padding:84px 0 96px}
.btx-hero__eyebrow{display:inline-flex;align-items:center;gap:9px;background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.16);padding:7px 15px;border-radius:999px;font-size:.78rem;letter-spacing:.08em;text-transform:uppercase;font-weight:600;color:#cfe9ff;margin-bottom:22px}
.btx-hero__dot{width:8px;height:8px;border-radius:50%;background:var(--btx-cyan);box-shadow:0 0 0 4px rgba(34,211,238,.25)}
.btx-hero h1{color:#fff;font-size:clamp(2.3rem,4.4vw,3.6rem);margin-bottom:18px}
.btx-hero h1 .accent{background:linear-gradient(90deg,var(--btx-cyan),var(--btx-blue));-webkit-background-clip:text;background-clip:text;color:transparent}
.btx-hero__lead{font-size:1.12rem;color:#c7d6ec;max-width:560px;margin-bottom:30px}
.btx-hero__cta{display:flex;gap:14px;flex-wrap:wrap;margin-bottom:34px}
.btx-hero__stats{display:flex;gap:34px;flex-wrap:wrap}
.btx-hero__stat strong{display:block;font-size:1.8rem;font-family:var(--btx-serif);color:#fff}
.btx-hero__stat span{font-size:.82rem;color:#9fb6d6;text-transform:uppercase;letter-spacing:.08em}
.btx-hero__art{position:relative}
.btx-hero__card{background:rgba(8,18,36,.55);backdrop-filter:blur(6px);border:1px solid rgba(255,255,255,.12);border-radius:var(--btx-radius);overflow:hidden;box-shadow:var(--btx-shadow-lg)}
.btx-hero__card img{width:100%;display:block}
.btx-hero__card-body{padding:18px 20px}
.btx-hero__card-body h3{color:#fff;font-size:1.1rem;margin:0 0 4px}
.btx-hero__card-body p{color:#a9c0de;font-size:.9rem;margin:0}

/* ============================ CATEGORY GRID ============================ */
.btx-cat-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.btx-cat-card{position:relative;border-radius:var(--btx-radius);overflow:hidden;color:#fff;display:block;background:var(--btx-navy-800);box-shadow:var(--btx-shadow);transition:transform .2s ease,box-shadow .2s ease}
.btx-cat-card:hover{transform:translateY(-4px);box-shadow:var(--btx-shadow-lg);color:#fff}
.btx-cat-card img{width:100%;height:170px;object-fit:cover;opacity:.92}
.btx-cat-card__body{position:absolute;left:0;right:0;bottom:0;padding:16px 18px;background:linear-gradient(to top,rgba(6,16,31,.92),rgba(6,16,31,0))}
.btx-cat-card__body h3{color:#fff;font-size:1.15rem;margin:0 0 2px}
.btx-cat-card__body p{color:#c7d6ec;font-size:.86rem;margin:0}
.btx-cat-card__arrow{position:absolute;top:14px;right:14px;width:34px;height:34px;border-radius:50%;background:rgba(255,255,255,.15);display:flex;align-items:center;justify-content:center;font-size:1rem}

/* ============================ FEATURE / VALUE ROW ============================ */
.btx-features{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.btx-feature{text-align:center;padding:28px 18px;border:1px solid var(--btx-line);border-radius:var(--btx-radius);background:#fff;transition:border-color .2s,box-shadow .2s}
.btx-feature:hover{border-color:var(--btx-blue);box-shadow:var(--btx-shadow)}
.btx-feature__icon{width:54px;height:54px;border-radius:14px;background:var(--btx-bg-tint);color:var(--btx-blue);display:flex;align-items:center;justify-content:center;margin:0 auto 16px;font-size:1.5rem}
.btx-feature h3{font-size:1.08rem;margin-bottom:6px}
.btx-feature p{color:var(--btx-muted);font-size:.92rem;margin:0}

/* ============================ CTA BANNER ============================ */
.btx-cta{background:linear-gradient(135deg,var(--btx-navy-800),var(--btx-navy-600));color:#fff;border-radius:20px;padding:48px;text-align:center;position:relative;overflow:hidden}
.btx-cta h2{color:#fff}
.btx-cta p{color:#c7d6ec;max-width:620px;margin:0 auto 26px}

/* ============================ FOOTER ============================ */
.btx-footer{background:var(--btx-navy-900);color:#9fb6d6;padding:64px 0 0;font-size:.92rem}
.btx-footer a{color:#bcd2ee}
.btx-footer a:hover{color:#fff}
.btx-footer__grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1.2fr;gap:40px;padding-bottom:48px}
.btx-footer h4{color:#fff;font-family:var(--btx-font);font-size:.82rem;text-transform:uppercase;letter-spacing:.12em;margin-bottom:18px}
.btx-footer ul{list-style:none;margin:0;padding:0}
.btx-footer li{margin-bottom:10px}
.btx-footer__brand .btx-logo__name{color:#fff}
.btx-footer__bottom{border-top:1px solid rgba(255,255,255,.08);padding:20px 0;display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;font-size:.84rem}

/* ============================ WOOCOMMERCE: CATALOG TABLE ============================ */
.btx-shop-layout{display:grid;grid-template-columns:260px 1fr;gap:36px;align-items:start}
.btx-shop-sidebar{position:sticky;top:200px}
.btx-shop-sidebar h4{font-family:var(--btx-font);font-size:.82rem;text-transform:uppercase;letter-spacing:.1em;color:var(--btx-muted);margin-bottom:12px}
.btx-shop-sidebar ul{list-style:none;margin:0 0 28px;padding:0}
.btx-shop-sidebar li a{display:block;padding:8px 12px;border-radius:8px;color:var(--btx-ink);font-size:.92rem}
.btx-shop-sidebar li a:hover,.btx-shop-sidebar .current a{background:var(--btx-bg-tint);color:var(--btx-blue)}

.btx-catalog{width:100%;border-collapse:collapse;background:#fff;border:1px solid var(--btx-line);border-radius:var(--btx-radius);overflow:hidden}
.btx-catalog thead th{background:var(--btx-bg-alt);text-align:left;padding:14px 16px;font-size:.8rem;text-transform:uppercase;letter-spacing:.06em;color:var(--btx-muted);font-family:var(--btx-font);border-bottom:1px solid var(--btx-line)}
.btx-catalog td{padding:16px;border-bottom:1px solid var(--btx-line);vertical-align:middle;font-size:.93rem}
.btx-catalog tbody tr:hover{background:var(--btx-bg-alt)}
.btx-catalog .col-cat{font-family:Consolas,monospace;color:var(--btx-muted);white-space:nowrap}
.btx-catalog .col-name a{font-weight:600;color:var(--btx-blue)}
.btx-catalog .col-structure img{max-height:54px;width:auto;margin:0 auto}
.btx-catalog .col-purity{text-align:center}
.btx-pricing-toggle{background:none;border:0;color:var(--btx-blue);font-weight:600;cursor:pointer;display:inline-flex;align-items:center;gap:6px;font-size:.92rem}
.btx-pricing-toggle .caret{transition:transform .2s}
.btx-pricing-toggle[aria-expanded=true] .caret{transform:rotate(180deg)}
.btx-pricing-row{display:none;background:var(--btx-bg-alt)!important}
.btx-pricing-row.open{display:table-row}
.btx-pricing-panel{padding:22px 28px}
.btx-pricing-grid{width:100%;max-width:620px;margin:0 auto}
.btx-pricing-grid table{width:100%;border-collapse:collapse}
.btx-pricing-grid th{text-align:left;font-family:var(--btx-font);font-size:.8rem;text-transform:uppercase;letter-spacing:.06em;color:var(--btx-muted);padding:8px 10px;border-bottom:2px solid var(--btx-line)}
.btx-pricing-grid td{padding:10px;border-bottom:1px solid var(--btx-line)}
.btx-pricing-grid .qty input{width:72px;padding:8px;border:1px solid var(--btx-line);border-radius:8px;text-align:center}
.btx-pricing-actions{text-align:center;margin-top:18px}

/* ============================ WOOCOMMERCE: SINGLE PRODUCT ============================ */
.btx-product{display:grid;grid-template-columns:1fr 1fr;gap:48px;align-items:start}
.btx-product__title{margin-bottom:8px}
.btx-product__desc{color:var(--btx-ink);margin-bottom:24px}
.btx-spec{width:100%;border-collapse:collapse;border:1px solid var(--btx-line);border-radius:var(--btx-radius);overflow:hidden}
.btx-spec th{text-align:left;width:42%;background:var(--btx-bg-alt);color:var(--btx-navy-800);font-weight:600;padding:12px 16px;font-size:.9rem;font-family:var(--btx-font);border-bottom:1px solid var(--btx-line)}
.btx-spec td{padding:12px 16px;font-size:.92rem;border-bottom:1px solid var(--btx-line)}
.btx-spec tr:last-child th,.btx-spec tr:last-child td{border-bottom:0}
.btx-buybox{border:1px solid var(--btx-line);border-radius:var(--btx-radius);padding:26px;box-shadow:var(--btx-shadow)}
.btx-tier{display:grid;grid-template-columns:1fr 96px;gap:14px;align-items:center;margin-bottom:12px}
.btx-tier--head{margin-bottom:6px;color:var(--btx-muted);font-size:.78rem;text-transform:uppercase;letter-spacing:.06em}
.btx-tier__unit{border:1.5px solid var(--btx-line);border-radius:10px;padding:13px 16px;font-weight:600;display:flex;justify-content:space-between;align-items:center}
.btx-tier input{width:100%;padding:11px;border:1px solid var(--btx-line);border-radius:10px;text-align:center}
.btx-buybox__ship{display:flex;align-items:center;gap:8px;color:var(--btx-muted);font-size:.9rem;margin:16px 0}
.btx-buybox__inquire{border-top:1px solid var(--btx-line);margin-top:20px;padding-top:20px}
.btx-badge{display:inline-flex;align-items:center;gap:6px;background:rgba(22,163,74,.1);color:var(--btx-success);font-size:.8rem;font-weight:600;padding:4px 12px;border-radius:999px}
.btx-badge--out{background:rgba(217,119,6,.1);color:var(--btx-warn)}

/* ============================ CHECKOUT STEPPER ============================ */
.btx-steps{display:flex;justify-content:center;gap:14px;background:var(--btx-bg-alt);padding:18px;border-radius:var(--btx-radius);margin-bottom:34px}
.btx-step{display:flex;align-items:center;gap:10px;color:var(--btx-muted);font-weight:600}
.btx-step__n{width:30px;height:30px;border-radius:50%;border:2px solid var(--btx-line);display:flex;align-items:center;justify-content:center;font-size:.9rem}
.btx-step.active .btx-step__n{background:var(--btx-blue);border-color:var(--btx-blue);color:#fff}
.btx-step.active{color:var(--btx-navy-800)}
.btx-step__sep{color:var(--btx-line)}

/* ============================ GENERIC PAGE ============================ */
.btx-page-hero{background:linear-gradient(135deg,var(--btx-navy-800),var(--btx-navy-600));color:#fff;padding:54px 0}
.btx-page-hero h1{color:#fff;margin:0}
.btx-breadcrumb{color:#9fb6d6;font-size:.86rem;margin-bottom:10px}
.btx-breadcrumb a{color:#bcd2ee}
.btx-prose{max-width:820px}
.btx-prose h2{margin-top:1.6em}

/* ============================ AI INSIGHTS ============================ */
.btx-ai-btn{display:inline-flex;align-items:center;gap:6px;cursor:pointer;border:1px solid transparent;
  background:linear-gradient(135deg,var(--btx-blue),var(--btx-cyan));color:#fff;font-weight:700;
  font-size:.85rem;padding:8px 14px;border-radius:999px;line-height:1;transition:transform .15s,box-shadow .15s}
.btx-ai-btn:hover{transform:translateY(-1px);box-shadow:0 6px 18px rgba(30,127,255,.35);color:#fff}
.btx-ai-btn span{letter-spacing:.04em}
.btx-ai-btn--sm{padding:3px 9px;font-size:.72rem;margin-left:8px;vertical-align:middle;gap:4px}

/* voice mic */
.btx-mic{border:0;background:transparent;color:var(--btx-muted);cursor:pointer;display:flex;align-items:center;padding:0 6px}
.btx-mic:hover{color:var(--btx-blue)}
.btx-mic--on{color:#e11d48;animation:btx-pulse 1s ease-in-out infinite}
@keyframes btx-pulse{0%,100%{opacity:1}50%{opacity:.4}}

/* modal */
.btx-ai-overlay{position:fixed;inset:0;z-index:200;background:rgba(6,16,31,.6);backdrop-filter:blur(3px);
  display:flex;align-items:flex-start;justify-content:center;padding:40px 16px;overflow:auto}
.btx-ai-overlay[hidden]{display:none}
.btx-ai-modal{background:#fff;border-radius:18px;max-width:760px;width:100%;box-shadow:var(--btx-shadow-lg);
  position:relative;animation:btx-rise .2s ease}
@keyframes btx-rise{from{opacity:0;transform:translateY(12px)}to{opacity:1;transform:none}}
.btx-ai-close{position:absolute;top:14px;right:18px;border:0;background:none;font-size:1.8rem;line-height:1;
  color:var(--btx-muted);cursor:pointer}
.btx-ai-close:hover{color:var(--btx-ink)}
.btx-ai-head{padding:24px 28px 16px;border-bottom:1px solid var(--btx-line)}
.btx-ai-chip{display:inline-flex;align-items:center;gap:6px;background:var(--btx-bg-tint);color:var(--btx-blue);
  font-weight:700;font-size:.74rem;text-transform:uppercase;letter-spacing:.1em;padding:5px 12px;border-radius:999px}
.btx-ai-head h3{margin:12px 0 0;font-size:1.5rem}
.btx-ai-body{padding:22px 28px 28px;max-height:70vh;overflow:auto}
.btx-ai-summary{font-size:1.02rem;color:var(--btx-ink)}
.btx-ai-block{margin-top:20px}
.btx-ai-block h4{font-family:var(--btx-font);font-size:.8rem;text-transform:uppercase;letter-spacing:.08em;
  color:var(--btx-muted);margin:0 0 10px}
.btx-ai-block p{margin:0}
.btx-ai-block ul{margin:0;padding-left:20px}
.btx-ai-block li{margin-bottom:6px}
.btx-ai-table{width:100%;border-collapse:collapse}
.btx-ai-table th{text-align:left;width:42%;padding:8px 10px;background:var(--btx-bg-alt);font-weight:600;
  font-size:.88rem;border-bottom:1px solid var(--btx-line);vertical-align:top}
.btx-ai-table td{padding:8px 10px;font-size:.88rem;border-bottom:1px solid var(--btx-line)}
.btx-ai-tags{display:flex;flex-wrap:wrap;gap:8px}
.btx-ai-tag{background:var(--btx-bg-tint);color:var(--btx-navy-800);font-size:.84rem;padding:5px 12px;border-radius:999px;font-weight:600}
.btx-ai-links{display:flex;flex-wrap:wrap;gap:10px}
.btx-ai-links a{display:inline-flex;align-items:center;gap:5px;border:1px solid var(--btx-line);border-radius:999px;
  padding:7px 14px;font-size:.86rem;font-weight:600}
.btx-ai-links a:hover{border-color:var(--btx-blue);background:var(--btx-bg-tint)}
.btx-ai-disclaimer{margin-top:24px;padding-top:16px;border-top:1px solid var(--btx-line);
  font-size:.8rem;color:var(--btx-muted);font-style:italic}
.btx-ai-note{background:rgba(217,119,6,.08);border:1px solid rgba(217,119,6,.25);color:#92600a;
  padding:12px 16px;border-radius:10px;font-size:.9rem}
.btx-ai-loading{display:flex;align-items:center;gap:12px;color:var(--btx-muted);padding:30px 0;font-size:.95rem}
.btx-ai-spin{width:22px;height:22px;border:3px solid var(--btx-line);border-top-color:var(--btx-blue);
  border-radius:50%;animation:btx-rot .8s linear infinite}
@keyframes btx-rot{to{transform:rotate(360deg)}}

/* ============================ RESPONSIVE ============================ */
@media (max-width:1024px){
  .btx-hero__inner{grid-template-columns:1fr;gap:34px;padding:60px 0}
  .btx-cat-grid{grid-template-columns:repeat(2,1fr)}
  .btx-features{grid-template-columns:repeat(2,1fr)}
  .btx-product{grid-template-columns:1fr}
  .btx-shop-layout{grid-template-columns:1fr}
  .btx-shop-sidebar{position:static}
  .btx-footer__grid{grid-template-columns:1fr 1fr}
}
@media (max-width:768px){
  .btx-search{display:none}
  .btx-menu{display:none;flex-direction:column;width:100%;background:var(--btx-navy-800)}
  .btx-menu.open{display:flex}
  .btx-menu .sub-menu{position:static;display:block;box-shadow:none;background:var(--btx-navy-700);min-width:0;border-radius:0}
  .btx-menu .sub-menu a{color:#dce7f7;padding-left:34px}
  .btx-menu .menu-item-has-children>a::after{display:none}
  .btx-burger{display:flex}
  .btx-families{display:none}
  .btx-cat-grid{grid-template-columns:1fr}
  .btx-features{grid-template-columns:1fr}
  .btx-footer__grid{grid-template-columns:1fr}
  .btx-catalog .col-structure{display:none}
  .btx-tier{grid-template-columns:1fr 70px}
}