/* ===== CSS Variables ===== */
:root {
  --navy: #0d1b2a;
  --navy-light: #122036;
  --blue: #1a56db;
  --blue-hover: #1648c0;
  --accent: #38bdf8;
  --text: #1e293b;
  --text-light: #64748b;
  --bg: #f8fafc;
  --white: #ffffff;
  --border: #e2e8f0;
  --shadow: 0 4px 20px rgba(0,0,0,.08);
  --shadow-md: 0 8px 32px rgba(0,0,0,.12);
  --radius: 8px;
  --radius-lg: 16px;
  --transition: .25s ease;
}

/* ===== Reset ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body { font-family: "PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif; color: var(--text); background: var(--bg); line-height: 1.7; }
a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }
ul { list-style: none; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }

/* ===== Utility ===== */
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.section { padding: 88px 0; }
.section-alt { background: var(--white); }
.section-dark { background: var(--navy); color: var(--white); }
.section-title { font-size: 2rem; font-weight: 700; text-align: center; margin-bottom: 12px; }
.section-sub { text-align: center; color: var(--text-light); font-size: 1.05rem; margin-bottom: 56px; }
.section-dark .section-sub { color: rgba(255,255,255,.6); }
.grid-2 { display: grid; grid-template-columns: repeat(2,1fr); gap: 32px; }
.grid-3 { display: grid; grid-template-columns: repeat(3,1fr); gap: 28px; }
.grid-4 { display: grid; grid-template-columns: repeat(4,1fr); gap: 24px; }
.btn { display: inline-flex; align-items: center; gap: 8px; padding: 13px 32px; border-radius: 6px; font-size: .95rem; font-weight: 600; transition: var(--transition); }
.btn-primary { background: var(--blue); color: var(--white); }
.btn-primary:hover { background: var(--blue-hover); transform: translateY(-2px); box-shadow: 0 6px 20px rgba(26,86,219,.35); }
.btn-outline { border: 2px solid rgba(255,255,255,.7); color: var(--white); }
.btn-outline:hover { background: rgba(255,255,255,.12); border-color: var(--white); }
.tag { display: inline-block; padding: 4px 12px; border-radius: 20px; font-size: .78rem; font-weight: 600; background: rgba(26,86,219,.1); color: var(--blue); }

/* ===== Navigation ===== */
.nav { position: fixed; top: 0; left: 0; right: 0; z-index: 1000; background: rgba(13,27,42,.95); backdrop-filter: blur(12px); border-bottom: 1px solid rgba(255,255,255,.08); transition: var(--transition); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.nav-logo { display: flex; align-items: center; gap: 12px; }
.nav-logo img { height: 40px; object-fit: contain; filter: brightness(0) invert(1); }
.nav-logo .company-name { color: var(--white); font-size: .9rem; font-weight: 600; line-height: 1.3; max-width: 160px; }
.nav-links { display: flex; align-items: center; gap: 8px; }
.nav-links a { color: rgba(255,255,255,.8); font-size: .9rem; padding: 8px 14px; border-radius: 5px; transition: var(--transition); }
.nav-links a:hover, .nav-links a.active { color: var(--white); background: rgba(255,255,255,.1); }
.nav-right { display: flex; align-items: center; gap: 12px; }
.lang-btn { color: rgba(255,255,255,.7); font-size: .85rem; padding: 6px 14px; border: 1px solid rgba(255,255,255,.25); border-radius: 20px; transition: var(--transition); }
.lang-btn:hover { color: var(--white); border-color: var(--white); }
.nav-cta { background: var(--blue); color: var(--white); font-size: .85rem; padding: 8px 20px; border-radius: 5px; font-weight: 600; transition: var(--transition); }
.nav-cta:hover { background: var(--blue-hover); }
.burger { display: none; flex-direction: column; gap: 5px; padding: 8px; }
.burger span { width: 22px; height: 2px; background: var(--white); border-radius: 2px; transition: var(--transition); }

/* ===== Hero ===== */
.hero { min-height: 100vh; background: linear-gradient(135deg, #0d1b2a 0%, #0f2947 45%, #0d1b2a 100%); display: flex; align-items: center; position: relative; overflow: hidden; padding-top: 68px; }
.hero::before { content: ''; position: absolute; inset: 0; background: radial-gradient(ellipse 80% 60% at 70% 50%, rgba(26,86,219,.18) 0%, transparent 70%); }
.hero-grid { position: absolute; inset: 0; opacity: .04; background-image: linear-gradient(rgba(255,255,255,.5) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.5) 1px, transparent 1px); background-size: 60px 60px; }
.hero-content { position: relative; z-index: 1; max-width: 720px; }
.hero-badge { display: inline-flex; align-items: center; gap: 8px; background: rgba(56,189,248,.12); border: 1px solid rgba(56,189,248,.3); color: var(--accent); font-size: .82rem; padding: 6px 16px; border-radius: 20px; margin-bottom: 28px; }
.hero h1 { font-size: 3.2rem; font-weight: 800; color: var(--white); line-height: 1.2; margin-bottom: 20px; }
.hero h1 span { color: var(--accent); }
.hero p { font-size: 1.15rem; color: rgba(255,255,255,.7); margin-bottom: 36px; max-width: 560px; }
.hero-btns { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 64px; }
.hero-stats { display: flex; gap: 48px; }
.stat-item .num { font-size: 2.4rem; font-weight: 800; color: var(--accent); line-height: 1; }
.stat-item .label { font-size: .82rem; color: rgba(255,255,255,.55); margin-top: 4px; }

/* ===== About ===== */
.about-intro { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; margin-bottom: 72px; }
.about-text h2 { font-size: 1.8rem; font-weight: 700; margin-bottom: 16px; }
.about-text p { color: var(--text-light); margin-bottom: 16px; }
.about-image { background: linear-gradient(135deg, var(--navy) 0%, #1a3a5c 100%); border-radius: var(--radius-lg); padding: 48px; display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.vm-card { background: rgba(255,255,255,.06); border-radius: var(--radius); padding: 24px; }
.vm-card .vm-icon { font-size: 1.6rem; margin-bottom: 10px; }
.vm-card h4 { color: var(--accent); font-size: .85rem; font-weight: 600; margin-bottom: 8px; }
.vm-card p { color: rgba(255,255,255,.7); font-size: .88rem; line-height: 1.6; }
.values-grid { display: grid; grid-template-columns: repeat(4,1fr); gap: 24px; }
.value-card { text-align: center; padding: 32px 20px; background: var(--white); border-radius: var(--radius-lg); box-shadow: var(--shadow); transition: var(--transition); }
.value-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); }
.value-icon { width: 56px; height: 56px; margin: 0 auto 16px; border-radius: 50%; background: linear-gradient(135deg, var(--blue), var(--accent)); display: flex; align-items: center; justify-content: center; font-size: 1.4rem; }
.value-card h3 { font-size: 1.1rem; font-weight: 700; margin-bottom: 8px; }
.value-card p { color: var(--text-light); font-size: .88rem; }

/* ===== Bilingual Toggle ===== */
.en { display: none; }
html.lang-en .zh { display: none; }
html.lang-en .en { display: revert; }
html.lang-en .en-block { display: block; }
html.lang-en .zh-block { display: none; }
.zh-block { display: block; }
.en-block { display: none; }

/* ===== Products ===== */
.products-grid { display: grid; grid-template-columns: repeat(2,1fr); gap: 28px; }
.product-card { background: var(--white); border-radius: var(--radius-lg); overflow: hidden; box-shadow: var(--shadow); transition: var(--transition); border: 1px solid var(--border); }
.product-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); }
.product-card-top { padding: 32px; background: linear-gradient(135deg, var(--navy) 0%, #1a3a5c 100%); position: relative; overflow: hidden; }
.product-card-top::after { content: ''; position: absolute; right: -20px; bottom: -20px; width: 120px; height: 120px; border-radius: 50%; background: rgba(56,189,248,.08); }
.product-icon { width: 52px; height: 52px; background: rgba(56,189,248,.15); border-radius: 12px; display: flex; align-items: center; justify-content: center; font-size: 1.5rem; margin-bottom: 16px; }
.product-card-top h3 { color: var(--white); font-size: 1.2rem; font-weight: 700; margin-bottom: 8px; }
.product-card-top p { color: rgba(255,255,255,.6); font-size: .88rem; line-height: 1.6; }
.product-card-body { padding: 24px 32px 28px; }
.feature-list { display: flex; flex-direction: column; gap: 10px; margin-bottom: 24px; }
.feature-list li { display: flex; align-items: center; gap: 10px; font-size: .9rem; color: var(--text-light); }
.feature-list li::before { content: ''; width: 6px; height: 6px; border-radius: 50%; background: var(--blue); flex-shrink: 0; }
.product-link { display: inline-flex; align-items: center; gap: 6px; color: var(--blue); font-size: .9rem; font-weight: 600; transition: var(--transition); }
.product-link:hover { gap: 10px; }

/* ===== Solutions ===== */
.solutions-tabs { display: flex; justify-content: center; gap: 8px; margin-bottom: 48px; }
.tab-btn { padding: 11px 28px; border-radius: 6px; font-size: .95rem; font-weight: 600; color: var(--text-light); background: var(--white); border: 2px solid var(--border); transition: var(--transition); }
.tab-btn.active, .tab-btn:hover { background: var(--blue); color: var(--white); border-color: var(--blue); }
.tab-panel { display: none; }
.tab-panel.active { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.solution-text h3 { font-size: 1.6rem; font-weight: 700; margin-bottom: 16px; }
.solution-text p { color: var(--text-light); margin-bottom: 28px; }
.solution-features { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.sol-feat { padding: 16px; background: var(--bg); border-radius: var(--radius); border-left: 3px solid var(--blue); }
.sol-feat h4 { font-size: .9rem; font-weight: 700; margin-bottom: 4px; color: var(--text); }
.sol-feat p { font-size: .83rem; color: var(--text-light); line-height: 1.5; }
.solution-img { background: linear-gradient(135deg, var(--navy) 0%, #1e3d6b 100%); border-radius: var(--radius-lg); padding: 40px; min-height: 320px; display: flex; align-items: center; justify-content: center; }
.solution-img-inner { text-align: center; color: rgba(255,255,255,.7); }
.solution-img-inner .big-icon { font-size: 4rem; margin-bottom: 16px; }
.solution-img-inner p { font-size: .9rem; }

/* ===== Cases ===== */
.cases-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 28px; }
.case-card { background: var(--white); border-radius: var(--radius-lg); padding: 32px; box-shadow: var(--shadow); border: 1px solid var(--border); transition: var(--transition); }
.case-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-md); border-color: rgba(26,86,219,.2); }
.case-tag { margin-bottom: 20px; }
.case-card h3 { font-size: 1.05rem; font-weight: 700; margin-bottom: 12px; line-height: 1.5; }
.case-card p { font-size: .88rem; color: var(--text-light); line-height: 1.7; margin-bottom: 20px; }
.case-metric { display: flex; align-items: center; gap: 8px; padding: 12px 16px; background: rgba(26,86,219,.06); border-radius: 8px; }
.case-metric .m-num { font-size: 1.3rem; font-weight: 800; color: var(--blue); }
.case-metric .m-label { font-size: .8rem; color: var(--text-light); }

/* ===== Honors ===== */
.honors-grid { display: grid; grid-template-columns: repeat(4,1fr); gap: 24px; }
.honor-card { text-align: center; padding: 36px 20px; background: rgba(255,255,255,.05); border: 1px solid rgba(255,255,255,.1); border-radius: var(--radius-lg); transition: var(--transition); }
.honor-card:hover { background: rgba(255,255,255,.09); transform: translateY(-4px); }
.honor-icon { font-size: 2.4rem; margin-bottom: 16px; }
.honor-card h3 { font-size: 1rem; font-weight: 700; color: var(--white); margin-bottom: 8px; }
.honor-card p { font-size: .83rem; color: rgba(255,255,255,.55); line-height: 1.6; }

/* ===== Contact ===== */
.contact-wrapper { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: start; }
.contact-info h2 { font-size: 1.8rem; font-weight: 700; margin-bottom: 12px; }
.contact-info .sub { color: var(--text-light); margin-bottom: 36px; }
.contact-items { display: flex; flex-direction: column; gap: 20px; }
.c-item { display: flex; align-items: flex-start; gap: 16px; }
.c-icon { width: 44px; height: 44px; background: rgba(26,86,219,.1); border-radius: 10px; display: flex; align-items: center; justify-content: center; font-size: 1.1rem; flex-shrink: 0; }
.c-item h4 { font-size: .85rem; font-weight: 600; color: var(--text-light); margin-bottom: 4px; }
.c-item p { font-size: 1rem; font-weight: 600; color: var(--text); }
.contact-map { background: linear-gradient(135deg, #e8f0fe 0%, #dbeafe 100%); border-radius: var(--radius-lg); overflow: hidden; min-height: 360px; display: flex; align-items: center; justify-content: center; border: 1px solid var(--border); }
.map-placeholder { text-align: center; color: var(--text-light); padding: 40px; }
.map-placeholder .map-icon { font-size: 3rem; margin-bottom: 12px; }

/* ===== Footer ===== */
.footer { background: var(--navy); border-top: 1px solid rgba(255,255,255,.06); padding: 48px 0 28px; }
.footer-inner { display: grid; grid-template-columns: 2fr 1fr 1fr auto; gap: 48px; margin-bottom: 40px; }
.footer-brand .logo-wrap { display: flex; align-items: center; gap: 12px; margin-bottom: 16px; }
.footer-brand img { height: 36px; object-fit: contain; filter: brightness(0) invert(1); }
.footer-brand .name { color: var(--white); font-size: .9rem; font-weight: 600; }
.footer-brand p { color: rgba(255,255,255,.45); font-size: .85rem; line-height: 1.7; max-width: 300px; }
.footer-col h4 { color: var(--white); font-size: .9rem; font-weight: 700; margin-bottom: 16px; }
.footer-col ul { display: flex; flex-direction: column; gap: 10px; }
.footer-col ul li a { color: rgba(255,255,255,.5); font-size: .85rem; transition: var(--transition); }
.footer-col ul li a:hover { color: var(--accent); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.06); padding-top: 24px; display: flex; align-items: center; justify-content: space-between; }
.footer-bottom p { color: rgba(255,255,255,.35); font-size: .8rem; }

/* ===== Scroll Animation ===== */
.fade-up { opacity: 0; transform: translateY(30px); transition: opacity .6s ease, transform .6s ease; }
.fade-up.visible { opacity: 1; transform: translateY(0); }

/* ===== Product Detail Page ===== */
.product-hero { background: linear-gradient(135deg, var(--navy) 0%, #0f2947 100%); padding: 120px 0 80px; }
.product-hero h1 { color: var(--white); font-size: 2.6rem; font-weight: 800; line-height: 1.2; margin-bottom: 20px; }
.product-hero p { color: rgba(255,255,255,.78); font-size: 1.05rem; margin-bottom: 32px; line-height: 1.75; }
.product-hero .hero-badge { color: var(--accent); }
.product-hero-content { max-width: 680px; }
.product-hero-content .badge { margin-bottom: 20px; }
.product-hero-content h1 { font-size: 2.6rem; font-weight: 800; color: var(--white); margin-bottom: 16px; line-height: 1.2; }
.product-hero-content p { color: rgba(255,255,255,.7); font-size: 1.1rem; margin-bottom: 32px; }
.features-section { padding: 80px 0; background: var(--bg); }
.features-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 24px; }
.feat-card { background: var(--white); border-radius: var(--radius-lg); padding: 28px; box-shadow: var(--shadow); border: 1px solid var(--border); }
.feat-card .feat-icon { font-size: 1.8rem; margin-bottom: 14px; }
.feat-card h3 { font-size: 1rem; font-weight: 700; margin-bottom: 8px; }
.feat-card p { font-size: .87rem; color: var(--text-light); line-height: 1.6; }
.tech-section { padding: 80px 0; background: var(--white); }
.tech-grid { display: grid; grid-template-columns: repeat(2,1fr); gap: 24px; margin-top: 48px; }
.tech-item { padding: 24px; border-radius: var(--radius); background: var(--bg); border-left: 4px solid var(--blue); }
.tech-item h4 { font-weight: 700; margin-bottom: 6px; }
.tech-item p { font-size: .87rem; color: var(--text-light); }
.cta-section { background: linear-gradient(135deg, var(--blue) 0%, #0d3fa8 100%); padding: 80px 0; text-align: center; }
.cta-section h2 { color: var(--white); font-size: 2rem; font-weight: 700; margin-bottom: 12px; }
.cta-section p { color: rgba(255,255,255,.75); margin-bottom: 36px; font-size: 1.05rem; }

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .hero h1 { font-size: 2.6rem; }
  .grid-4, .values-grid, .honors-grid { grid-template-columns: repeat(2,1fr); }
  .about-intro { gap: 40px; }
}
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-links.open { display: flex; flex-direction: column; position: fixed; top: 68px; left: 0; right: 0; background: var(--navy); padding: 16px 24px 24px; border-bottom: 1px solid rgba(255,255,255,.08); }
  .burger { display: flex; }
  .nav-cta { display: none; }
  .hero h1 { font-size: 2rem; }
  .hero-stats { gap: 28px; }
  .about-intro, .contact-wrapper, .tab-panel.active { grid-template-columns: 1fr; }
  .products-grid, .cases-grid { grid-template-columns: 1fr; }
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
  .section { padding: 60px 0; }
  .section-title { font-size: 1.6rem; }
  .footer-inner { grid-template-columns: 1fr; gap: 28px; }
  .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }
  .solutions-tabs { flex-wrap: wrap; }
  .solution-img { display: none; }
  .features-grid { grid-template-columns: 1fr; }
  .honors-grid, .values-grid { grid-template-columns: repeat(2,1fr); }
}