/*
Theme Name: COX Filter
Theme URI: https://filterbag.org
Author: FilterBag.org
Author URI: https://filterbag.org
Description: Minimal COX-style WordPress theme for industrial liquid filter bags. Clean corporate nav with product mega-dropdown, SEO/GEO ready, featured-snippet FAQ.
Version: 1.0
License: GPL v2 or later
Text Domain: cox-filter
*/

:root{
  --navy:#002B5C;          /* COX deep navy */
  --blue:#007AC2;          /* COX bright blue */
  --blue-dark:#005A9C;
  --ink:#16202B;
  --muted:#5B6B7B;
  --bg:#FFFFFF;
  --bg-alt:#F4F7FA;
  --line:#E2E8F0;
  --radius:6px;
  --maxw:1180px;
}

*{box-sizing:border-box}
body{margin:0;font-family:'Segoe UI',Helvetica,Arial,'Microsoft YaHei',sans-serif;color:var(--ink);background:var(--bg);line-height:1.65;font-size:16px}
a{color:var(--blue);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;height:auto}
.container{max-width:var(--maxw);margin:0 auto;padding:0 20px}

/* ---------- Header ---------- */
.site-header{background:var(--bg);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:50}
.header-inner{max-width:var(--maxw);margin:0 auto;padding:0 20px;display:flex;align-items:center;justify-content:space-between;height:64px}
.logo{display:flex;align-items:center;gap:10px;font-weight:700;color:var(--navy);font-size:19px;letter-spacing:-.3px}
.logo svg{height:34px;width:auto;display:block}
.logo:hover{text-decoration:none}

.nav{display:flex;align-items:center;gap:2px;list-style:none;margin:0;padding:0}
.nav > li{position:relative}
.nav > li > a,.nav .drop-toggle{display:flex;align-items:center;gap:6px;padding:0 14px;height:64px;color:var(--navy);font-weight:600;font-size:14.5px;cursor:pointer}
.nav > li > a:hover,.nav .drop-toggle:hover{color:var(--blue);text-decoration:none;background:var(--bg-alt)}
.nav .caret{font-size:10px;opacity:.7}

/* Mega dropdown */
.mega{position:absolute;top:64px;left:0;background:#fff;border:1px solid var(--line);border-top:3px solid var(--blue);box-shadow:0 14px 34px rgba(0,43,92,.14);display:none;padding:22px;min-width:640px;grid-template-columns:repeat(3,1fr);gap:22px}
.has-mega:hover .mega{display:grid}
.mega h4{margin:0 0 10px;font-size:12px;text-transform:uppercase;letter-spacing:.6px;color:var(--muted)}
.mega a{display:block;padding:5px 0;color:var(--ink);font-size:14px;font-weight:500}
.mega a:hover{color:var(--blue);text-decoration:none}
.mega .col{border-right:1px solid var(--line);padding-right:18px}
.mega .col:last-child{border-right:none}

.nav-toggle{display:none;background:none;border:none;cursor:pointer;padding:8px}
.nav-toggle span{display:block;width:24px;height:2px;background:var(--navy);margin:5px 0}

/* ---------- Hero ---------- */
.hero{background:linear-gradient(120deg,var(--navy) 0%,var(--blue-dark) 100%);color:#fff;padding:72px 0}
.hero h1{font-size:38px;line-height:1.15;margin:0 0 14px;font-weight:700;letter-spacing:-.5px}
.hero p{font-size:18px;max-width:740px;color:#D7E6F5;margin:0 0 26px}
.hero .btn-row{display:flex;gap:12px;flex-wrap:wrap}
.btn{display:inline-block;padding:12px 22px;border-radius:var(--radius);font-weight:700;font-size:15px}
.btn-primary{background:var(--blue);color:#fff}
.btn-primary:hover{background:#0090d8;text-decoration:none}
.btn-ghost{border:1px solid rgba(255,255,255,.5);color:#fff}
.btn-ghost:hover{border-color:#fff;text-decoration:none}

/* ---------- Trust strip ---------- */
.trust{background:var(--bg-alt);border-bottom:1px solid var(--line);padding:16px 0}
.trust .container{display:flex;gap:28px;flex-wrap:wrap;justify-content:center;color:var(--muted);font-size:14px;font-weight:600}
.trust span{display:flex;align-items:center;gap:8px}

/* ---------- Sections ---------- */
.section{padding:56px 0}
.section.alt{background:var(--bg-alt)}
.section h2{font-size:26px;margin:0 0 8px;color:var(--navy)}
.section .lead{color:var(--muted);margin:0 0 30px;font-size:16px}

/* Product cards */
.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px;transition:box-shadow .15s,border-color .15s}
.card:hover{box-shadow:0 8px 22px rgba(0,43,92,.08);border-color:var(--blue)}
.card h3{margin:0 0 8px;font-size:17px;color:var(--navy)}
.card p{margin:0 0 12px;color:var(--muted);font-size:14px}
.card a.more{font-weight:600;font-size:14px}

/* Why list */
.why{display:grid;grid-template-columns:repeat(2,1fr);gap:16px}
.why li{list-style:none;padding:14px 16px;background:#fff;border:1px solid var(--line);border-left:3px solid var(--blue);border-radius:var(--radius);font-size:15px}
ul.why{margin:0;padding:0}

/* ---------- Page banner (breadcrumb) ---------- */
.page-banner{background:linear-gradient(120deg,var(--navy),var(--blue-dark));color:#fff;padding:30px 0}
.page-banner h1{margin:6px 0 0;font-size:28px}
.breadcrumb{font-size:13px;color:#Bcd4ea}
.breadcrumb a{color:#Bcd4ea}
.breadcrumb a:hover{color:#fff}
.breadcrumb span.sep{margin:0 8px;opacity:.6}

.page-body{padding:48px 0}
.page-body .container{max-width:880px}
.page-body h2{color:var(--navy);margin-top:30px}
.page-body h3{color:var(--blue-dark)}
.page-body p,.page-body li{font-size:16px;color:#23303d}

/* ---------- Footer ---------- */
.site-footer{background:var(--navy);color:#C7D6E5;padding:40px 0 24px;font-size:14px}
.site-footer .cols{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.site-footer h4{color:#fff;font-size:14px;margin:0 0 12px}
.site-footer a{color:#C7D6E5}
.site-footer a:hover{color:#fff}
.footer-bottom{border-top:1px solid rgba(255,255,255,.12);margin-top:28px;padding-top:16px;color:#8ba3ba;font-size:13px}

/* ---------- Responsive ---------- */
@media (max-width:900px){
  .cards,.why,.site-footer .cols{grid-template-columns:1fr 1fr}
  .mega{min-width:auto;width:90vw;grid-template-columns:1fr 1fr}
}
@media (max-width:640px){
  .nav{display:none;position:absolute;top:64px;left:0;right:0;background:#fff;flex-direction:column;box-shadow:0 10px 20px rgba(0,0,0,.1)}
  .nav.open{display:flex}
  .nav > li{width:100%}
  .nav > li > a,.nav .drop-toggle{height:50px;width:100%}
  .mega{position:static;display:none!important;box-shadow:none;border:none;grid-template-columns:1fr;min-width:0}
  .has-mega.open .mega{display:block}
  .nav-toggle{display:block}
  .cards,.why,.site-footer .cols{grid-template-columns:1fr}
  .hero h1{font-size:28px}
}