/* ===== 基础变量与重置 ===== */
:root {
    --c-navy: #0a2540;
    --c-navy-2: #123a5e;
    --c-blue: #1e5f8c;
    --c-cyan: #0bb58a;
    --c-cyan-d: #098765;
    --c-bg: #f5f7fa;
    --c-bg-alt: #eef2f6;
    --c-text: #1f2d3d;
    --c-text-soft: #5b6b7b;
    --c-white: #ffffff;
    --shadow: 0 8px 30px rgba(10, 37, 64, .08);
    --shadow-lg: 0 16px 48px rgba(10, 37, 64, .14);
    --radius: 14px;
    --maxw: 1160px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    font-family: "Microsoft YaHei", "PingFang SC", "Hiragino Sans GB", "Segoe UI", system-ui, sans-serif;
    color: var(--c-text);
    background: var(--c-bg);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; }

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ===== 顶部导航 ===== */
.site-header {
    position: fixed; top: 0; left: 0; right: 0; z-index: 100;
    background: rgba(10, 37, 64, .92);
    backdrop-filter: blur(8px);
    transition: all .3s ease;
}
.site-header.scrolled { box-shadow: var(--shadow); }
.nav-wrap { display: flex; align-items: center; justify-content: space-between; height: 66px; }
.logo { display: flex; align-items: center; gap: 10px; color: var(--c-white); }
.logo-mark {
    font-weight: 800; font-size: 18px; letter-spacing: 1px;
    background: linear-gradient(135deg, var(--c-cyan), var(--c-blue));
    padding: 4px 8px; border-radius: 8px;
}
.logo-text { font-size: 18px; font-weight: 700; }
.main-nav { display: flex; gap: 28px; }
.main-nav a { color: rgba(255,255,255,.82); font-size: 15px; transition: color .2s; position: relative; }
.main-nav a:hover { color: var(--c-cyan); }
.main-nav a::after {
    content: ""; position: absolute; left: 0; bottom: -6px; width: 0; height: 2px;
    background: var(--c-cyan); transition: width .25s;
}
.main-nav a:hover::after { width: 100%; }

.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 6px; }
.nav-toggle span { width: 24px; height: 2px; background: var(--c-white); transition: .3s; }

/* ===== 英雄区 ===== */
.hero {
    background: linear-gradient(135deg, var(--c-navy) 0%, var(--c-navy-2) 55%, var(--c-blue) 100%);
    color: var(--c-white); padding: 150px 0 90px; position: relative; overflow: hidden;
}
.hero::after {
    content: ""; position: absolute; right: -120px; top: -120px; width: 420px; height: 420px;
    background: radial-gradient(circle, rgba(11,181,138,.25), transparent 70%); border-radius: 50%;
}
.hero-inner { display: grid; grid-template-columns: 1.3fr 1fr; gap: 50px; align-items: center; position: relative; z-index: 1; }
.hero-tag { color: var(--c-cyan); font-weight: 600; letter-spacing: 2px; font-size: 14px; margin-bottom: 18px; }
.hero-text h1 { font-size: 52px; line-height: 1.15; font-weight: 800; margin-bottom: 22px; }
.hero-sub { color: rgba(255,255,255,.8); font-size: 17px; max-width: 520px; margin-bottom: 32px; }
.hero-btns { display: flex; gap: 16px; flex-wrap: wrap; }
.btn {
    display: inline-block; padding: 13px 30px; border-radius: 30px; font-weight: 600; font-size: 15px;
    transition: transform .2s, box-shadow .2s; cursor: pointer;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary { background: var(--c-cyan); color: #fff; box-shadow: 0 8px 24px rgba(11,181,138,.4); }
.btn-primary:hover { box-shadow: 0 12px 32px rgba(11,181,138,.55); }
.btn-ghost { border: 1.5px solid rgba(255,255,255,.4); color: #fff; }
.btn-ghost:hover { background: rgba(255,255,255,.1); }

.hero-stats { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.stat {
    background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.14);
    border-radius: var(--radius); padding: 22px 20px; text-align: center; backdrop-filter: blur(4px);
}
.stat strong { display: block; font-size: 34px; font-weight: 800; color: var(--c-cyan); line-height: 1; }
.stat .unit { font-size: 16px; margin-left: 2px; }
.stat span { font-size: 13px; color: rgba(255,255,255,.72); margin-top: 8px; display: block; }

/* ===== 通用区块 ===== */
.section { padding: 90px 0; }
.section-alt { background: var(--c-bg-alt); }
.section-head { text-align: center; margin-bottom: 54px; }
.eyebrow { color: var(--c-cyan-d); font-weight: 700; letter-spacing: 3px; font-size: 13px; }
.section-head h2 { font-size: 36px; font-weight: 800; margin: 10px 0 14px; color: var(--c-navy); }
.section-desc { color: var(--c-text-soft); max-width: 620px; margin: 0 auto; }

/* ===== 关于我们 ===== */
.about-grid { display: grid; grid-template-columns: 1.4fr 1fr; gap: 50px; align-items: start; }
.about-text p { margin-bottom: 18px; font-size: 16px; color: var(--c-text); }
.about-text strong { color: var(--c-navy); }
.about-points { list-style: none; display: flex; flex-direction: column; gap: 16px; }
.about-points li { display: flex; gap: 14px; background: var(--c-white); padding: 18px 20px; border-radius: var(--radius); box-shadow: var(--shadow); }
.about-points .ico { color: var(--c-cyan); font-size: 14px; line-height: 1.7; }
.about-points h4 { font-size: 16px; color: var(--c-navy); margin-bottom: 2px; }
.about-points p { font-size: 14px; color: var(--c-text-soft); }

/* ===== 产品 ===== */
.product-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.product-card {
    background: var(--c-white); border-radius: var(--radius); padding: 28px 26px;
    box-shadow: var(--shadow); transition: transform .25s, box-shadow .25s; border-top: 3px solid transparent;
}
.product-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-top-color: var(--c-cyan); }
.pc-head { display: flex; align-items: center; gap: 12px; margin-bottom: 14px; }
.pc-no { font-size: 22px; font-weight: 800; color: rgba(30,95,140,.25); }
.pc-head h3 { font-size: 19px; color: var(--c-navy); font-weight: 700; }
.pc-desc { font-size: 14px; color: var(--c-text-soft); margin-bottom: 16px; min-height: 62px; }
.pc-spec { list-style: none; border-top: 1px dashed #e3e9ef; padding-top: 14px; }
.pc-spec li { font-size: 13.5px; color: var(--c-text); padding: 5px 0 5px 18px; position: relative; }
.pc-spec li::before { content: "▸"; position: absolute; left: 0; color: var(--c-cyan); }

/* ===== 技术优势 ===== */
.tech-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.tech-item { background: var(--c-white); border-radius: var(--radius); padding: 26px 24px; box-shadow: var(--shadow); border-left: 4px solid var(--c-cyan); }
.tech-item h4 { font-size: 17px; color: var(--c-navy); margin-bottom: 10px; }
.tech-item p { font-size: 14px; color: var(--c-text-soft); }

/* ===== 应用场景 ===== */
.app-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.app-card { background: var(--c-white); border-radius: var(--radius); padding: 28px 22px; box-shadow: var(--shadow); text-align: center; transition: transform .25s; }
.app-card:hover { transform: translateY(-5px); }
.app-card h4 { font-size: 18px; color: var(--c-navy); margin-bottom: 10px; }
.app-card p { font-size: 13.5px; color: var(--c-text-soft); }

/* ===== 联系我们 ===== */
.contact { background: linear-gradient(135deg, var(--c-navy), var(--c-navy-2)); color: var(--c-white); }
.contact .section-head h2, .contact .eyebrow { color: #fff; }
.contact .eyebrow { color: var(--c-cyan); }
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: center; }
.contact-info { display: flex; flex-direction: column; gap: 18px; }
.ci-item { border-left: 3px solid var(--c-cyan); padding-left: 16px; }
.ci-label { font-size: 13px; color: var(--c-cyan); letter-spacing: 1px; }
.ci-item p { font-size: 16px; color: rgba(255,255,255,.92); }
.contact-note { background: rgba(255,255,255,.07); border: 1px solid rgba(255,255,255,.14); border-radius: var(--radius); padding: 32px; }
.contact-note h4 { font-size: 20px; margin-bottom: 12px; }
.contact-note p { color: rgba(255,255,255,.78); font-size: 15px; margin-bottom: 24px; }

/* ===== 页脚 ===== */
.site-footer { background: #061826; color: rgba(255,255,255,.6); padding: 30px 0; text-align: center; font-size: 14px; }
.footer-sub { margin-top: 6px; font-size: 13px; color: rgba(255,255,255,.4); }

/* ===== 响应式 ===== */
@media (max-width: 980px) {
    .hero-inner { grid-template-columns: 1fr; }
    .hero-stats { margin-top: 10px; }
    .about-grid, .contact-grid { grid-template-columns: 1fr; }
    .product-grid, .tech-grid { grid-template-columns: repeat(2, 1fr); }
    .app-grid { grid-template-columns: repeat(2, 1fr); }
    .hero-text h1 { font-size: 42px; }
}
@media (max-width: 640px) {
    .main-nav {
        position: absolute; top: 66px; left: 0; right: 0; flex-direction: column; gap: 0;
        background: var(--c-navy); max-height: 0; overflow: hidden; transition: max-height .3s ease;
    }
    .main-nav.open { max-height: 360px; box-shadow: var(--shadow); }
    .main-nav a { padding: 15px 24px; border-bottom: 1px solid rgba(255,255,255,.08); }
    .nav-toggle { display: flex; }
    .hero-text h1 { font-size: 34px; }
    .section { padding: 64px 0; }
    .section-head h2 { font-size: 28px; }
    .product-grid, .tech-grid, .app-grid { grid-template-columns: 1fr; }
    .hero-stats { grid-template-columns: 1fr 1fr; }
}