:root {
--primary: #0a4d8c;
--primary-light: #1565c0;
--primary-dark: #063463;
--accent: #00b4d8;
--accent-light: #48cae4;
--dark: #0d1b2a;
--dark-2: #1b263b;
--gray-50: #f8fafc;
--gray-100: #f1f5f9;
--gray-200: #e2e8f0;
--gray-300: #cbd5e1;
--gray-400: #94a3b8;
--gray-500: #64748b;
--gray-600: #475569;
--gray-700: #334155;
--gray-800: #1e293b;
--white: #ffffff;
--gradient-primary: linear-gradient(135deg, #0a4d8c 0%, #00b4d8 100%);
--gradient-dark: linear-gradient(135deg, #0d1b2a 0%, #1b263b 50%, #0a4d8c 100%);
--shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
--shadow-md: 0 4px 20px rgba(0,0,0,0.1);
--shadow-lg: 0 10px 40px rgba(0,0,0,0.15);
--radius-sm: 6px;
--radius-md: 10px;
--radius-lg: 16px;
--radius-xl: 24px;
--transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
--max-width: 1280px;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body { font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", Arial, sans-serif; line-height: 1.7; color: var(--gray-700); background: var(--white); overflow-x: hidden; }
img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; transition: var(--transition); }
ul { list-style: none; }
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* === 顶部信息条 === */
.top-bar { background: var(--dark); color: var(--gray-300); font-size: 13px; padding: 8px 0; }
.top-bar .container { display: flex; justify-content: space-between; align-items: center; }
.top-bar-info { display: flex; gap: 28px; }
.top-bar-info span { display: flex; align-items: center; gap: 6px; }
.top-bar-info svg { width: 14px; height: 14px; color: var(--accent); }
.top-bar-right { display: flex; gap: 20px; }
.top-bar-right a:hover { color: var(--accent); }

/* === 导航栏 === */
.header { position: sticky; top: 0; z-index: 1000; background: rgba(255,255,255,0.98); backdrop-filter: blur(12px); box-shadow: var(--shadow-sm); transition: var(--transition); }
.header.scrolled { box-shadow: var(--shadow-md); }
.nav { display: flex; justify-content: space-between; align-items: center; height: 72px; }
.logo { display: flex; align-items: center; gap: 10px; font-size: 22px; font-weight: 700; color: var(--dark); flex-shrink: 0; }
.logo-icon { width: 42px; height: 42px; background: var(--gradient-primary); border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center; color: var(--white); font-size: 18px; font-weight: 800; box-shadow: 0 4px 12px rgba(10,77,140,0.3); }
.logo-text { display: flex; flex-direction: column; line-height: 1.2; }
.logo-text .logo-name { font-size: 20px; }
.logo-text .logo-sub { font-size: 11px; color: var(--gray-400); letter-spacing: 1px; }
.nav-menu { display: flex; align-items: center; }
.nav-item { position: relative; }
.nav-link { display: flex; align-items: center; gap: 4px; padding: 0 24px; height: 72px; font-size: 16px; font-weight: 600; color: var(--gray-700); position: relative; cursor: pointer; }
.nav-link::after { content: ''; position: absolute; bottom: 0; left: 50%; width: 0; height: 3px; background: var(--gradient-primary); transition: var(--transition); transform: translateX(-50%); }
.nav-link:hover { color: var(--primary); }
.nav-link:hover::after { width: 60%; }
.nav-arrow { font-size: 10px; transition: var(--transition); }
.nav-item:hover .nav-arrow { transform: rotate(180deg); }
.dropdown { position: absolute; top: 72px; left: 50%; transform: translateX(-50%) translateY(10px); background: var(--white); min-width: 220px; border-radius: var(--radius-md); box-shadow: var(--shadow-lg); opacity: 0; visibility: hidden; transition: var(--transition); padding: 8px 0; }
.nav-item:hover .dropdown { opacity: 1; visibility: visible; transform: translateX(-50%) translateY(0); }
.dropdown::before { content: ''; position: absolute; top: -8px; left: 50%; transform: translateX(-50%) rotate(45deg); width: 16px; height: 16px; background: var(--white); }
.dropdown-item { display: block; padding: 12px 24px; font-size: 14px; color: var(--gray-600); transition: var(--transition); border-left: 3px solid transparent; }
.dropdown-item:hover { background: var(--gray-50); color: var(--primary); border-left-color: var(--accent); padding-left: 28px; }
.nav-cta { margin-left: 16px; }
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 14px 36px; font-size: 15px; font-weight: 600; border-radius: var(--radius-md); cursor: pointer; transition: var(--transition); border: none; letter-spacing: 0.5px; }
.btn-primary { background: var(--gradient-primary); color: var(--white); box-shadow: 0 4px 20px rgba(10,77,140,0.35); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 30px rgba(10,77,140,0.45); }
.btn-dark { background: var(--dark); color: var(--white); }
.btn-dark:hover { background: var(--primary); transform: translateY(-2px); }
.nav-cta .btn { padding: 10px 28px; font-size: 14px; }
.mobile-toggle { display: none; background: none; border: none; cursor: pointer; padding: 8px; }
.mobile-toggle span { display: block; width: 24px; height: 3px; background: var(--dark); margin: 5px 0; transition: var(--transition); border-radius: 2px; }

/* === 页面Banner === */
.page-banner { background: var(--gradient-dark); padding: 80px 0 60px; color: var(--white); position: relative; overflow: hidden; }
.page-banner::before { content: ''; position: absolute; top: -100px; right: -100px; width: 400px; height: 400px; background: radial-gradient(circle, rgba(0,180,216,0.15) 0%, transparent 70%); border-radius: 50%; }
.page-banner::after { content: ''; position: absolute; bottom: -100px; left: -100px; width: 400px; height: 400px; background: radial-gradient(circle, rgba(10,77,140,0.2) 0%, transparent 70%); border-radius: 50%; }
.banner-content { position: relative; z-index: 2; }
.breadcrumb { display: flex; align-items: center; gap: 8px; font-size: 14px; color: rgba(255,255,255,0.6); margin-bottom: 20px; }
.breadcrumb a:hover { color: var(--accent-light); }
.breadcrumb .separator { color: var(--gray-400); }
.breadcrumb .current { color: var(--white); }
.page-banner h1 { font-size: 36px; font-weight: 700; color: var(--white); }

/* === 产品详情主体 === */
.product-detail { padding: 64px 0; }
.product-main { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; margin-bottom: 64px; }

/* 产品图库 */
.product-gallery { }
.gallery-main { width: 100%; height: 440px; border-radius: var(--radius-lg); overflow: hidden; box-shadow: var(--shadow-md); margin-bottom: 16px; background: var(--gray-50); position: relative; }
.gallery-main img { width: 100%; height: 100%; object-fit: cover; }
.gallery-main .gallery-badge { position: absolute; top: 16px; left: 16px; background: var(--gradient-primary); color: var(--white); font-size: 12px; font-weight: 600; padding: 6px 16px; border-radius: 20px; z-index: 2; }
.gallery-thumbs { display: flex; gap: 12px; }
.gallery-thumb { width: 100px; height: 80px; border-radius: var(--radius-sm); overflow: hidden; cursor: pointer; border: 3px solid transparent; transition: var(--transition); }
.gallery-thumb.active { border-color: var(--accent); }
.gallery-thumb:hover { border-color: var(--accent-light); }
.gallery-thumb img { width: 100%; height: 100%; object-fit: cover; }

/* 产品信息 */
.product-info { }
.product-info-category { display: inline-block; background: rgba(10,77,140,0.08); color: var(--primary); font-size: 13px; font-weight: 600; padding: 4px 14px; border-radius: 20px; margin-bottom: 12px; }
.product-info h1 { font-size: 32px; font-weight: 700; color: var(--dark); line-height: 1.4; margin-bottom: 16px; }
.product-info-desc { font-size: 15px; color: var(--gray-500); line-height: 1.8; margin-bottom: 28px; padding-bottom: 28px; border-bottom: 1px solid var(--gray-100); }

.product-info-specs { margin-bottom: 28px; }
.product-info-specs-title { font-size: 16px; font-weight: 600; color: var(--dark); margin-bottom: 16px; }
.spec-row { display: flex; padding: 10px 0; border-bottom: 1px solid var(--gray-100); }
.spec-row:last-child { border-bottom: none; }
.spec-label { width: 130px; font-size: 14px; color: var(--gray-400); flex-shrink: 0; }
.spec-value { font-size: 14px; color: var(--gray-700); font-weight: 500; }
.spec-value .highlight { color: var(--primary); font-weight: 700; }

.product-info-actions { display: flex; gap: 12px; margin-top: 32px; }
.product-info-actions .btn { flex: 1; }
.product-tags { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 20px; }
.product-tag { display: inline-flex; align-items: center; gap: 4px; padding: 6px 14px; background: var(--gray-50); border: 1px solid var(--gray-200); border-radius: 20px; font-size: 12px; color: var(--gray-500); }

/* === Tab区域 === */
.product-tabs { margin-bottom: 64px; }
.tabs-header { display: flex; gap: 0; border-bottom: 2px solid var(--gray-100); margin-bottom: 40px;}
.tab-btn { padding: 16px 32px; font-size: 16px; font-weight: 600; color: var(--gray-400); cursor: pointer; border: none; background: none; position: relative; white-space: nowrap; transition: var(--transition); }
.tab-btn::after { content: ''; position: absolute; bottom: -2px; left: 0; right: 0; height: 3px; background: var(--gradient-primary); transform: scaleX(0); transition: var(--transition); }
.tab-btn:hover { color: var(--primary); }
.tab-btn.active { color: var(--primary); }
.tab-btn.active::after { transform: scaleX(1); }
.tab-panel { display: none; }
.tab-panel.active { display: block; animation: fadeIn 0.4s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }

/* 产品概述 */
.overview-content { font-size: 16px; line-height: 2; color: var(--gray-600); }
.overview-content p { margin-bottom: 20px; }
.overview-content h3 { font-size: 22px; font-weight: 700; color: var(--dark); margin: 32px 0 16px; }
.overview-content img { width: 100%; border-radius: var(--radius-md); margin: 24px 0; box-shadow: var(--shadow-md); }
.overview-content ul.text-list { margin: 16px 0 24px 20px; }
.overview-content ul.text-list li { list-style: disc; margin-bottom: 8px; }

/* HGT121 专属样式 */
.hgt-metrics { display: grid; grid-template-columns: repeat(4,1fr); gap: 16px; margin: 28px 0 36px; }
.hgt-metric { background: linear-gradient(135deg,#0a4d8c,#1565c0); border-radius: 12px; padding: 20px 16px; text-align: center; color: #fff; }
.hgt-metric .num { font-size: 28px; font-weight: 700; color: #ffd9a8; line-height: 1.2; }
.hgt-metric .num span { font-size: 14px; font-weight: 400; color: #fff; opacity: .9; margin-left: 3px; }
.hgt-metric .lab { font-size: 12px; opacity: .85; margin-top: 4px; }
.hgt-arch { background: var(--gray-50); border: 1px solid var(--gray-200); border-radius: 12px; padding: 24px; margin: 28px 0; }
.hgt-arch h4 { font-size: 18px; color: var(--dark); margin-bottom: 6px; }
.hgt-arch .cap { font-size: 13px; color: var(--gray-500); margin-bottom: 16px; }
.hgt-arch svg { width: 100%; height: auto; display: block; }
.fg-group { background: var(--gray-50); border: 1px solid var(--gray-200); border-radius: 12px; padding: 24px 28px; margin-bottom: 20px; }
.fg-group h4 { font-size: 18px; color: var(--primary); padding-left: 14px; border-left: 4px solid var(--primary-light); margin-bottom: 14px; }
.fg-table { width: 100%; border-collapse: collapse; font-size: 14px; }
.fg-table th { background: #e8f0fd; color: var(--primary); border: 1px solid var(--gray-200); padding: 9px 14px; text-align: left; width: 200px; font-weight: 700; }
.fg-table td { border: 1px solid var(--gray-200); padding: 9px 14px; color: var(--gray-600); }
.hgt-cta { background: linear-gradient(135deg,var(--dark-2),var(--primary)); border-radius: 12px; color: #fff; padding: 28px 32px; margin-top: 32px; display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 16px; }
.hgt-cta h4 { font-size: 20px; margin-bottom: 4px; color: #fff; }
.hgt-cta p { font-size: 14px; opacity: .9; color: rgba(255,255,255,0.8); }
.hgt-cta .badge { background: rgba(255,255,255,.15); border: 1px solid rgba(255,255,255,.35); border-radius: 8px; padding: 10px 22px; font-size: 14px; }

/* 参数表 */
.specs-table { width: 100%; border-collapse: collapse; }
.specs-table th { background: var(--gray-50); padding: 16px 24px; font-size: 14px; font-weight: 600; color: var(--dark); text-align: left; border-bottom: 2px solid var(--gray-200); }
.specs-table td { padding: 14px 24px; font-size: 14px; color: var(--gray-600); border-bottom: 1px solid var(--gray-100); }
.specs-table tr:hover td { background: var(--gray-50); }
.specs-table .spec-name { font-weight: 600; color: var(--dark); width: 200px; }

/* 特性卡片 */
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.feature-card { padding: 26px 24px 22px; background: var(--white); border-radius: 14px; border: 1px solid var(--gray-200); box-shadow: 0 2px 10px rgba(10,77,140,0.05); transition: transform .2s, box-shadow .2s; }
.feature-card:hover { transform: translateY(-4px); box-shadow: 0 10px 26px rgba(10,77,140,0.12); }
.feature-icon { width: 52px; height: 52px; border-radius: 12px; background: #e8f0fd; display: flex; align-items: center; justify-content: center; font-size: 26px; margin-bottom: 14px; }
.feature-card h4 { font-size: 18px; font-weight: 700; color: var(--primary-dark); margin-bottom: 8px; }
.feature-card p { font-size: 14px; color: var(--gray-600); line-height: 1.7; }
.feature-card .hl { color: #e8720c; font-weight: 700; }

/* 应用场景 */
.scenarios-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.scenario-card { border-radius: var(--radius-md); overflow: hidden; position: relative; height: 240px; cursor: pointer; box-shadow: var(--shadow-sm); }
.scenario-card img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; transition: transform 0.6s ease; }
.scenario-card:hover img { transform: scale(1.1); }
.scenario-overlay { position: absolute; inset: 0; background: linear-gradient(180deg, transparent 30%, rgba(13,27,42,0.9) 100%); display: flex; flex-direction: column; justify-content: flex-end; padding: 20px; }
.scenario-card h4 { font-size: 18px; font-weight: 700; color: var(--white); margin-bottom: 4px; }
.scenario-card p { font-size: 13px; color: rgba(255,255,255,0.7); }

/* === 相关产品 === */
.related-products { padding: 80px 0; background: var(--gray-50); }
.related-header { text-align: center; margin-bottom: 48px; }
.related-header h2 { font-size: 30px; font-weight: 700; color: var(--dark); margin-bottom: 12px; }
.related-header p { font-size: 15px; color: var(--gray-500); }
.related-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.product-card { background: var(--white); border-radius: var(--radius-lg); overflow: hidden; box-shadow: var(--shadow-sm); transition: var(--transition); border: 1px solid var(--gray-100); cursor: pointer; }
.product-card:hover { transform: translateY(-8px); box-shadow: var(--shadow-lg); }
.product-card-img { width: 100%; height: 180px; overflow: hidden; background: var(--gray-100); }
.product-card-img img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.6s ease; }
.product-card:hover .product-card-img img { transform: scale(1.1); }
.product-card-body { padding: 20px; }
.product-card-body h4 { font-size: 16px; font-weight: 700; color: var(--dark); margin-bottom: 6px; }
.product-card-body p { font-size: 13px; color: var(--gray-500); line-height: 1.6; }

/* === 咨询CTA === */
.cta-bar { padding: 56px 0; background: var(--gradient-dark); color: var(--white); text-align: center; position: relative; overflow: hidden; }
.cta-bar::before { content: ''; position: absolute; top: 0; right: 0; width: 60%; height: 100%; background: radial-gradient(ellipse at right, rgba(0,180,216,0.15) 0%, transparent 60%); }
.cta-bar-content { position: relative; z-index: 2; }
.cta-bar h2 { font-size: 30px; font-weight: 700; margin-bottom: 16px; }
.cta-bar p { font-size: 16px; color: rgba(255,255,255,0.7); margin-bottom: 32px; }
.cta-bar-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.cta-bar .btn-outline { background: transparent; color: var(--white); border: 2px solid rgba(255,255,255,0.5); }
.cta-bar .btn-outline:hover { background: rgba(255,255,255,0.1); border-color: var(--white); }

/* === 页脚 === */
.footer { background: var(--dark); color: var(--gray-400); padding: 80px 0 0; }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: 48px; margin-bottom: 64px; }
.footer-brand .logo { color: var(--white); margin-bottom: 20px; }
.footer-brand p { font-size: 14px; color: var(--gray-400); line-height: 1.8; margin-bottom: 24px; }
.footer-contact { display: flex; flex-direction: column; gap: 12px; }
.footer-contact-item { display: flex; align-items: center; gap: 10px; font-size: 14px; color: var(--gray-400); }
.footer-contact-item svg { width: 16px; height: 16px; color: var(--accent); flex-shrink: 0; }
.footer-col h4 { font-size: 16px; font-weight: 700; color: var(--white); margin-bottom: 20px; }
.footer-col ul li { margin-bottom: 12px; }
.footer-col ul li a { font-size: 14px; color: var(--gray-400); }
.footer-col ul li a:hover { color: var(--accent); padding-left: 6px; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.08); padding: 24px 0; display: flex; justify-content: space-between; align-items: center; font-size: 13px; }
.footer-bottom a { color: var(--gray-400); }
.footer-bottom a:hover { color: var(--accent); }

.back-to-top { position: fixed; bottom: 30px; right: 30px; width: 48px; height: 48px; background: var(--gradient-primary); color: var(--white); border-radius: 50%; display: flex; align-items: center; justify-content: center; cursor: pointer; opacity: 0; visibility: hidden; transition: var(--transition); z-index: 999; box-shadow: var(--shadow-md); border: none; }
.back-to-top.visible { opacity: 1; visibility: visible; }
.back-to-top:hover { transform: translateY(-4px); }
.back-to-top svg { width: 22px; height: 22px; }

.fade-up { opacity: 0; transform: translateY(40px); transition: opacity 0.8s ease, transform 0.8s ease; }
.fade-up.visible { opacity: 1; transform: translateY(0); }

@media (max-width: 1024px) {
.product-main { grid-template-columns: 1fr; }
.features-grid { grid-template-columns: repeat(2, 1fr); }
.scenarios-grid { grid-template-columns: repeat(2, 1fr); }
.related-grid { grid-template-columns: repeat(2, 1fr); }
.footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
}
@media (max-width: 768px) {
.top-bar { display: none; }
.nav-menu { display: none; }
.nav-cta { display: none; }
.mobile-toggle { display: block; }
.product-info h1 { font-size: 24px; }
.scenarios-grid { grid-template-columns: 1fr; }
.features-grid { grid-template-columns: 1fr; }
.related-grid { grid-template-columns: 1fr 1fr; }
.footer-grid { grid-template-columns: 1fr; }
.footer-bottom { flex-direction: column; gap: 12px; text-align: center; }
.page-banner h1 { font-size: 26px; }
.specs-table .spec-name { width: 120px; }
.hgt-metrics { grid-template-columns: repeat(2, 1fr); }
.fg-table th { width: 120px; }
.product-info-actions { flex-direction: column; }
}

/* 资料下载 */
.download-list { display: flex; flex-direction: column; gap: 16px; }
.download-item { display: flex; align-items: center; gap: 20px; padding: 24px 28px; background: var(--gray-50); border-radius: var(--radius-md); border: 1px solid var(--gray-100); transition: var(--transition); }
.download-item:hover { background: var(--white); box-shadow: var(--shadow-md); border-color: var(--accent); transform: translateY(-2px); }
.download-icon { width: 52px; height: 52px; border-radius: var(--radius-sm); background: linear-gradient(135deg, #0a4d8c, #00b4d8); display: flex; align-items: center; justify-content: center; color: var(--white); flex-shrink: 0; }
.download-icon svg { width: 26px; height: 26px; }
.download-info { flex: 1; }
.download-info h4 { font-size: 16px; font-weight: 600; color: var(--dark); margin-bottom: 4px; }
.download-info p { font-size: 13px; color: var(--gray-500); }
.download-btn { display: inline-flex; align-items: center; gap: 8px; padding: 10px 24px; font-size: 14px; font-weight: 600; color: var(--primary); border: 2px solid var(--primary); border-radius: var(--radius-sm); cursor: pointer; transition: var(--transition); background: transparent; text-decoration: none; }
.download-btn:hover { background: var(--primary); color: var(--white); }
.download-btn svg { width: 16px; height: 16px; }
@media (max-width: 768px) { .download-item { flex-direction: column; text-align: center; } }

/* 常见问题 */
.product-faq { padding: 80px 0; background: var(--gray-50); }
.faq-header { text-align: center; margin-bottom: 48px; }
.faq-header h2 { font-size: 30px; font-weight: 700; color: var(--dark); margin-bottom: 12px; }
.faq-header p { font-size: 15px; color: var(--gray-500); }
.product-faq .faq-list { max-width: 900px; margin: 0 auto; }
.product-faq .faq-item {
background: var(--white);
border: 1px solid var(--gray-200);
border-radius: 12px;
margin-bottom: 14px;
overflow: hidden;
transition: box-shadow .3s ease;
}
.product-faq .faq-item:hover { box-shadow: 0 8px 24px rgba(10,77,140,.08); }
.product-faq .faq-question {
display: flex;
align-items: center;
justify-content: space-between;
padding: 18px 24px;
cursor: pointer;
user-select: none;
}
.product-faq .faq-question h3 { font-size: 16px; color: var(--dark); margin: 0; }
.product-faq .faq-toggle {
flex-shrink: 0;
width: 28px;
height: 28px;
border-radius: 50%;
background: var(--primary-light);
color: #fff;
display: flex;
align-items: center;
justify-content: center;
font-size: 18px;
font-weight: 700;
transition: transform .3s ease, background .3s ease;
}
.product-faq .faq-item.active .faq-toggle { transform: rotate(45deg); background: var(--accent); }
.product-faq .faq-answer {
max-height: 0;
overflow: hidden;
padding: 0 24px;
color: var(--gray-600);
font-size: 14px;
line-height: 1.8;
transition: max-height .35s ease, padding .35s ease;
}
.product-faq .faq-item.active .faq-answer { max-height: 400px; padding: 0 24px 20px; }
@media (max-width: 768px) {
.product-faq .faq-question { padding: 15px 18px; }
.product-faq .faq-question h3 { font-size: 15px; }
.product-faq .faq-answer { padding: 0 18px; }
.product-faq .faq-item.active .faq-answer { padding: 0 18px 16px; }
}