/* 上海泰通调节阀 - 精密过程控制风格 */
:root{
  --c-bg:#ffffff; --c-bg2:#f5f8fb; --c-bg3:#eef3f8;
  --c-ink:#1e2a3a; --c-ink2:#56657a; --c-line:#e3e9f0;
  --c-primary:#1f3a5f; --c-primary2:#2b4d78;
  --c-accent:#0ea3c4; --c-accentd:#0b87a3;
  --radius:10px; --maxw:1180px;
  --shadow:0 1px 3px rgba(20,40,70,.06),0 8px 24px rgba(20,40,70,.05);
}
*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{margin:0; background:var(--c-bg); color:var(--c-ink); font-family:"Segoe UI",system-ui,-apple-system,"PingFang SC","Microsoft YaHei",sans-serif; font-size:16px; line-height:1.7; -webkit-font-smoothing:antialiased;}
img{max-width:100%; height:auto; display:block;}
a{color:var(--c-primary); text-decoration:none;}
a:hover{color:var(--c-accentd);}
h1,h2,h3,h4{color:var(--c-ink); line-height:1.3; margin:0 0 .6em;}
p{margin:0 0 1em;}
ul,ol{margin:0 0 1em; padding-left:1.3em;}
.container{width:100%; max-width:var(--maxw); margin:0 auto; padding:0 20px;}
.section{padding:56px 0;}
.section-light{background:var(--c-bg2);}
.section-title{font-size:1.5rem; position:relative; padding-left:14px; margin-bottom:1.4rem;}
.section-title::before{content:""; position:absolute; left:0; top:6px; bottom:6px; width:4px; border-radius:3px; background:linear-gradient(var(--c-accent),var(--c-primary));}
.section-action{margin-top:26px; text-align:center;}
.btn{display:inline-block; padding:11px 22px; border-radius:8px; font-weight:600; font-size:.95rem; border:1px solid transparent; transition:.18s; cursor:pointer;}
.btn-primary{background:var(--c-primary); color:#fff;}
.btn-primary:hover{background:var(--c-primary2); color:#fff;}
.btn-secondary{background:#fff; color:var(--c-primary); border-color:var(--c-line);}
.btn-secondary:hover{border-color:var(--c-primary); color:var(--c-primary);}
.btn-outline{background:transparent; color:var(--c-primary); border-color:var(--c-primary);}
.btn-outline:hover{background:var(--c-primary); color:#fff;}
.link-arrow{display:inline-block; color:var(--c-accentd); font-weight:600;}
.site-header{position:sticky; top:0; z-index:50; background:rgba(255,255,255,.92); backdrop-filter:saturate(160%) blur(8px); border-bottom:1px solid var(--c-line);}
.header-inner{display:flex; align-items:center; gap:18px; height:68px;}
.logo-link{display:flex; align-items:center;}
.logo-link img{height:34px; width:auto; background:transparent;}
.main-nav ul{display:flex; gap:4px; list-style:none; margin:0; padding:0;}
.main-nav a{display:block; padding:9px 14px; color:var(--c-ink2); font-weight:500; border-radius:7px; font-size:.96rem;}
.main-nav a:hover{color:var(--c-primary); background:var(--c-bg2);}
.main-nav a.active{color:var(--c-primary); background:var(--c-bg3);}
.header-phone{margin-left:auto; display:flex; align-items:center; gap:7px; background:var(--c-primary); color:#fff; padding:8px 16px; border-radius:8px; font-weight:700; font-size:1rem;}
.header-phone:hover{background:var(--c-primary2); color:#fff;}
.phone-icon{font-size:1.1rem;}
.nav-toggle{display:none; flex-direction:column; gap:5px; margin-left:auto; background:none; border:0; cursor:pointer; padding:8px;}
.nav-toggle span{width:24px; height:2px; background:var(--c-ink); border-radius:2px;}
.breadcrumbs{background:var(--c-bg2); border-bottom:1px solid var(--c-line);}
.breadcrumbs ol{list-style:none; display:flex; flex-wrap:wrap; gap:6px; margin:0; padding:10px 0; font-size:.85rem; color:var(--c-ink2);}
.breadcrumbs li::after{content:"/"; margin-left:6px; color:var(--c-line);}
.breadcrumbs li:last-child::after{content:"";}
.breadcrumbs a{color:var(--c-ink2);}
.page-header{background:linear-gradient(120deg,var(--c-bg3),var(--c-bg)); border-bottom:1px solid var(--c-line); padding:46px 0 38px;}
.page-header h1{font-size:2.1rem; margin-bottom:.4em;}
.page-lead{font-size:1.05rem; color:var(--c-ink2); max-width:760px;}
.hero{background:radial-gradient(1200px 400px at 80% -10%,rgba(14,163,196,.12),transparent),linear-gradient(120deg,#f3f7fb,#ffffff); border-bottom:1px solid var(--c-line); padding:64px 0 56px;}
.hero-grid{display:grid; grid-template-columns:1.05fr .95fr; gap:40px; align-items:center;}
.hero-text h1{font-size:2.7rem; margin-bottom:.5em; letter-spacing:-.5px;}
.hero-sub{display:block; font-size:1.15rem; font-weight:500; color:var(--c-accentd); margin-top:.4em;}
.hero-text p{color:var(--c-ink2); font-size:1.08rem; max-width:520px;}
.hero-actions{margin-top:24px; display:flex; gap:14px; flex-wrap:wrap;}
.hero-products{display:grid; grid-template-columns:1fr 1fr; gap:14px;}
.hero-product-card{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:14px; box-shadow:var(--shadow); transition:.2s;}
.hero-product-card:hover{transform:translateY(-3px); border-color:var(--c-accent);}
.hero-product-card img{height:140px; object-fit:contain; margin:0 auto 10px; background:var(--c-bg2); border-radius:8px;}
.hero-product-card span{display:block; font-size:.86rem; color:var(--c-ink2); text-align:center;}
.need-grid{display:grid; grid-template-columns:repeat(4,1fr); gap:18px;}
.need-card{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:22px; box-shadow:var(--shadow); transition:.2s;}
.need-card:hover{border-color:var(--c-accent); transform:translateY(-3px);}
.need-icon{font-size:1.6rem; color:var(--c-accent); margin-bottom:10px;}
.need-card h3{font-size:1.1rem;}
.drive-grid{display:grid; grid-template-columns:repeat(3,1fr); gap:18px;}
.drive-card{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:24px; box-shadow:var(--shadow); transition:.2s; color:var(--c-ink);}
.drive-card:hover{border-color:var(--c-primary);}
.drive-card h3{font-size:1.2rem;}
.link-arrow{margin-top:8px;}
.selection-cta{display:grid; grid-template-columns:1.3fr 1fr; gap:30px; align-items:center; background:#fff; border:1px solid var(--c-line); border-radius:14px; padding:34px; box-shadow:var(--shadow);}
.selection-cta h2{font-size:1.5rem;}
.selection-cta-params{display:flex; flex-wrap:wrap; gap:10px; justify-content:flex-end;}
.param-chip{background:var(--c-bg3); color:var(--c-primary); border:1px solid var(--c-line); padding:8px 14px; border-radius:20px; font-size:.9rem; font-weight:600;}
.product-grid{display:grid; grid-template-columns:repeat(3,1fr); gap:20px;}
.product-card{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); overflow:hidden; box-shadow:var(--shadow); transition:.2s;}
.product-card:hover{transform:translateY(-4px); border-color:var(--c-accent);}
.product-card-link{display:block; color:var(--c-ink);}
.product-card-image{background:var(--c-bg2); padding:18px; aspect-ratio:4/3; display:flex; align-items:center; justify-content:center;}
.product-card-image img{max-height:170px; object-fit:contain;}
.product-card h3{font-size:1.05rem; margin:0; padding:14px 16px 0;}
.product-card p{padding:6px 16px 16px; color:var(--c-ink2); font-size:.9rem; margin:0; min-height:48px;}
.category-grid{display:grid; grid-template-columns:repeat(3,1fr); gap:18px;}
.category-grid.four-col{grid-template-columns:repeat(4,1fr);}
.category-card{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:22px; box-shadow:var(--shadow); transition:.2s; color:var(--c-ink); position:relative;}
.category-card:hover{border-color:var(--c-primary); transform:translateY(-3px);}
.category-card h3{font-size:1.15rem;}
.category-card p{color:var(--c-ink2); font-size:.92rem;}
.category-count{display:inline-block; margin-top:8px; font-size:.8rem; color:var(--c-accentd); font-weight:600;}
.empty-note{color:var(--c-ink2);}
.app-grid{display:grid; grid-template-columns:repeat(2,1fr); gap:20px;}
.application-grid{display:grid; grid-template-columns:repeat(2,1fr); gap:20px;}
.application-card{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:22px; box-shadow:var(--shadow); transition:.2s; color:var(--c-ink);}
.application-card:hover{border-color:var(--c-accent); transform:translateY(-3px);}
.application-card h3{font-size:1.15rem;}
.application-card p{color:var(--c-ink2); font-size:.92rem;}
.card-link{display:inline-block; margin-top:10px; color:var(--c-accentd); font-weight:600;}
.app-card{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:20px; box-shadow:var(--shadow); transition:.2s; color:var(--c-ink);}
.app-card:hover{border-color:var(--c-accent); transform:translateY(-3px);}
.app-card h3{font-size:1.1rem;}
.knowledge-grid{display:grid; grid-template-columns:repeat(3,1fr); gap:20px;}
.knowledge-card{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:22px; box-shadow:var(--shadow); transition:.2s; color:var(--c-ink);}
.knowledge-card:hover{border-color:var(--c-accent); transform:translateY(-3px);}
.knowledge-card h3{font-size:1.08rem;}
.knowledge-card p{color:var(--c-ink2); font-size:.9rem;}
.faq-list,.faq-preview{display:grid; gap:12px;}
.faq-item{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:4px 18px; box-shadow:var(--shadow);}
.faq-item summary{cursor:pointer; font-weight:600; padding:14px 0; list-style:none; position:relative; padding-right:28px;}
.faq-item summary::-webkit-details-marker{display:none;}
.faq-item summary::after{content:"+"; position:absolute; right:0; top:12px; font-size:1.3rem; color:var(--c-accentd); font-weight:700;}
.faq-item[open] summary::after{content:"-";}
.faq-answer{padding:0 0 16px; color:var(--c-ink2);}
.detail-layout{display:grid; grid-template-columns:1fr 320px; gap:34px; align-items:start;}
.detail-main h2{font-size:1.3rem; margin-top:1.6em; border-left:4px solid var(--c-accent); padding-left:12px;}
.detail-main h2:first-child{margin-top:0;}
.direct-answer{background:linear-gradient(180deg,rgba(14,163,196,.1),rgba(14,163,196,.04)); border:1px solid var(--c-line); border-left:4px solid var(--c-accent); border-radius:var(--radius); padding:18px 20px; margin:0 0 8px;}
.direct-answer h2{margin:0 0 .4em; font-size:1.05rem; border:0; padding:0; color:var(--c-accentd);}
.selection-note{background:var(--c-bg2); border:1px solid var(--c-line); border-radius:var(--radius); padding:16px 18px; margin-top:20px;}
.selection-note h3{margin:0 0 .4em; font-size:1.05rem;}
.detail-sidebar{display:grid; gap:18px; position:sticky; top:88px;}
.sidebar-block{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:18px; box-shadow:var(--shadow);}
.sidebar-block h3{font-size:1.05rem; margin-top:0;}
.contact-list,.related-list{list-style:none; margin:0; padding:0;}
.contact-list li,.related-list li{padding:5px 0; border-bottom:1px dashed var(--c-line); font-size:.92rem;}
.contact-list li:last-child,.related-list li:last-child{border-bottom:0;}
.param-list,.risk-list{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:14px 18px; box-shadow:var(--shadow);}
.param-list li,.risk-list li{padding:5px 0;}
.product-header{background:linear-gradient(120deg,var(--c-bg3),var(--c-bg)); border-bottom:1px solid var(--c-line); padding:40px 0;}
.product-header-grid{display:grid; grid-template-columns:.9fr 1.1fr; gap:36px; align-items:center;}
.product-header-image{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:18px; box-shadow:var(--shadow);}
.product-header-image img{height:320px; object-fit:contain; margin:0 auto; background:var(--c-bg2); border-radius:8px;}
.product-header-info h1{font-size:1.9rem;}
.product-definition{font-size:1.05rem; color:var(--c-ink2); background:#fff; border:1px solid var(--c-line); border-left:4px solid var(--c-accent); border-radius:8px; padding:12px 16px;}
.product-tags{display:flex; flex-wrap:wrap; gap:8px; margin:14px 0;}
.product-tag{background:var(--c-bg3); color:var(--c-primary); border:1px solid var(--c-line); padding:5px 12px; border-radius:18px; font-size:.82rem; font-weight:600;}
.product-actions{display:flex; gap:12px; flex-wrap:wrap; margin-top:8px;}
.selection-tool{display:grid; grid-template-columns:330px 1fr; gap:26px; align-items:start;}
.filter-panel{background:#fff; border:1px solid var(--c-line); border-radius:14px; padding:20px; box-shadow:var(--shadow); position:sticky; top:88px;}
.filter-panel-head{display:flex; justify-content:space-between; align-items:center; margin-bottom:10px;}
.filter-panel-head h2{margin:0; font-size:1.2rem;}
.filter-panel-head button{background:var(--c-bg2); border:1px solid var(--c-line); border-radius:7px; padding:6px 14px; cursor:pointer; color:var(--c-ink2); font-weight:600;}
.filter-group{border-top:1px solid var(--c-line); padding:14px 0;}
.filter-group h3{font-size:1rem; margin:0 0 10px; color:var(--c-primary);}
.filter-options{display:flex; flex-wrap:wrap; gap:8px 14px;}
.filter-opt{display:flex; align-items:center; gap:6px; font-size:.9rem; color:var(--c-ink2); cursor:pointer;}
.filter-cond{border-top:1px dashed var(--c-line); padding-top:10px;}
.filter-note{font-size:.82rem; color:var(--c-ink2); margin:8px 0 0;}
.result-panel{min-width:0;}
.result-head{display:flex; align-items:baseline; gap:12px; margin-bottom:14px;}
.result-count{color:var(--c-accentd); font-weight:600; font-size:.9rem;}
.selection-results{display:grid; grid-template-columns:repeat(2,1fr); gap:16px;}
.selection-disclaimer{margin-top:18px; font-size:.85rem; color:var(--c-ink2); background:var(--c-bg2); border:1px solid var(--c-line); border-radius:8px; padding:12px 14px;}
.no-result{grid-column:1/-1; color:var(--c-ink2);}
.guide-grid{display:grid; grid-template-columns:repeat(3,1fr); gap:18px;}
.guide-card{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:22px; box-shadow:var(--shadow); transition:.2s; color:var(--c-ink);}
.guide-card:hover{border-color:var(--c-accent); transform:translateY(-3px);}
.guide-card h3{font-size:1.1rem;}
.guide-card p{color:var(--c-ink2); font-size:.9rem;}
.cta-box{background:linear-gradient(120deg,var(--c-primary),var(--c-primary2)); color:#fff; border-radius:14px; padding:32px; text-align:center;}
.cta-box h2{color:#fff;}
.cta-box p{color:rgba(255,255,255,.85);}
.cta-actions{display:flex; gap:14px; justify-content:center; flex-wrap:wrap; margin-top:16px;}
.cta-actions .btn-primary{background:#fff; color:var(--c-primary);}
.cta-actions .btn-secondary{background:transparent; color:#fff; border-color:#fff;}
.about-layout{display:grid; grid-template-columns:1fr 320px; gap:34px; align-items:start;}
.about-main h2{font-size:1.35rem; margin-top:1.5em; border-left:4px solid var(--c-accent); padding-left:12px;}
.about-main h2:first-child{margin-top:0;}
.about-list{background:#fff; border:1px solid var(--c-line); border-radius:var(--radius); padding:14px 20px; box-shadow:var(--shadow);}
.about-list li{margin:.4em 0;}
.about-sidebar{position:sticky; top:88px;}
.about-grid{display:grid; grid-template-columns:1.4fr 1fr; gap:30px; align-items:start;}
.about-contact ul{list-style:none; margin:0; padding:0;}
.about-contact li{padding:6px 0; border-bottom:1px dashed var(--c-line);}
.detail-main table{width:100%; border-collapse:collapse; margin:1em 0; font-size:.92rem;}
.detail-main table th,.detail-main table td{border:1px solid var(--c-line); padding:9px 12px; text-align:left;}
.detail-main table th{background:var(--c-bg3); color:var(--c-primary);}
.site-footer{background:var(--c-bg3); border-top:1px solid var(--c-line); color:var(--c-ink2); margin-top:40px;}
.footer-grid{display:grid; grid-template-columns:1.6fr 1fr 1fr 1.2fr; gap:28px; padding:46px 0 30px;}
.footer-logo img{height:30px; width:auto; background:transparent; margin-bottom:12px;}
.footer-brand p{font-size:.9rem; max-width:340px;}
.footer-links h3,.footer-contact h3{font-size:1rem; color:var(--c-primary); margin:0 0 12px;}
.footer-links ul,.footer-contact ul{list-style:none; margin:0; padding:0;}
.footer-links li,.footer-contact li{padding:5px 0; font-size:.9rem;}
.footer-contact a{color:var(--c-primary); font-weight:600;}
.footer-bottom{border-top:1px solid var(--c-line); padding:14px 0; font-size:.82rem; color:var(--c-ink2);}
.footer-bottom-inner{display:flex; align-items:center; justify-content:space-between; gap:18px; flex-wrap:wrap;}
.footer-bottom p{margin:0;}
.footer-bottom .site-statement{text-align:right;}
.footer-bottom a{color:var(--c-primary2); text-decoration:underline;}
.footer-bottom a:hover{color:var(--c-primary);}
@media(max-width:1024px){
  .hero-grid{grid-template-columns:1fr;}
  .selection-tool{grid-template-columns:1fr;}
  .filter-panel{position:static;}
  .need-grid,.drive-grid,.category-grid,.product-grid,.knowledge-grid,.guide-grid{grid-template-columns:repeat(2,1fr);}
  .category-grid.four-col{grid-template-columns:repeat(2,1fr);}
  .application-grid,.app-grid{grid-template-columns:1fr;}
  .footer-grid{grid-template-columns:1fr 1fr;}
}
@media(max-width:768px){
  .nav-toggle{display:flex;}
  .main-nav{display:none; position:absolute; top:68px; left:0; right:0; background:#fff; border-bottom:1px solid var(--c-line); box-shadow:var(--shadow);}
  .main-nav.open{display:block;}
  .main-nav ul{flex-direction:column; padding:8px;}
  .main-nav a{padding:12px 14px;}
  .header-phone{margin-left:0;}
  .hero-text h1{font-size:2.1rem;}
  .detail-layout,.about-layout{grid-template-columns:1fr;}
  .detail-sidebar,.about-sidebar{position:static;}
  .selection-cta{grid-template-columns:1fr;}
  .selection-cta-params{justify-content:flex-start;}
  .about-grid{grid-template-columns:1fr;}
  .selection-results{grid-template-columns:1fr;}
}
@media(max-width:480px){
  .need-grid,.drive-grid,.category-grid,.product-grid,.knowledge-grid,.guide-grid,.category-grid.four-col{grid-template-columns:1fr;}
  .footer-grid{grid-template-columns:1fr;}
  .footer-bottom-inner{flex-direction:column; align-items:flex-start; gap:6px;}
  .footer-bottom .site-statement{text-align:left;}
  .product-header-grid{grid-template-columns:1fr; gap:20px;}
  .hero-products{grid-template-columns:1fr 1fr;}
  .section{padding:40px 0;}
}