/* style.css - 顶级科技企业全局皮肤 */
:root {
    --bg-dark: #0a0a0c;       /* 曜石黑 */
    --bg-card: #121216;       /* 深空灰 */
    --primary: #2563eb;       /* 科技蓝 */
    --primary-light: #60a5fa; /* 亮蓝色 */
    --text-main: #f8fafc;     /* 纯白文字 */
    --text-muted: #94a3b8;    /* 质感灰字 */
    --border: #27272a;        /* 隐形边框 */
}

* { margin: 0; padding: 0; box-sizing: border-box; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif; }
body { background-color: var(--bg-dark); color: var(--text-main); line-height: 1.7; -webkit-font-smoothing: antialiased; }
a { text-decoration: none; color: inherit; transition: all 0.3s ease; }
ul { list-style: none; }

/* 悬浮导航栏 */
.header {
    position: fixed; top: 0; width: 100%; height: 80px;
    background: rgba(10, 10, 12, 0.85); backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(255,255,255,0.05); z-index: 1000;
}
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.nav-wrapper { display: flex; justify-content: space-between; align-items: center; height: 100%; }
.logo a { font-size: 26px; font-weight: 800; color: var(--text-main); letter-spacing: -1px; }
.logo span { color: var(--primary); }
.nav ul { display: flex; gap: 32px; margin-top: 15px;}
.nav a { font-size: 15px; font-weight: 600; color: var(--text-muted); }
.nav a:hover, .nav a.active { color: var(--text-main); text-shadow: 0 0 10px rgba(96, 165, 250, 0.5); }

/* 各页面公共 Banner */
.page-hero { padding: 180px 20px 80px; text-align: center; background: radial-gradient(circle at 50% 0%, #1e3a8a, transparent 60%); border-bottom: 1px solid var(--border); }
.page-hero h1 { font-size: 3.5rem; font-weight: 800; margin-bottom: 16px; letter-spacing: -1px; }
.page-hero p { font-size: 1.2rem; color: var(--text-muted); max-width: 650px; margin: 0 auto; }

/* 按钮与卡片 */
.btn { display: inline-block; padding: 14px 36px; background: var(--primary); color: #fff; border-radius: 6px; font-weight: 600; font-size: 15px; border: 1px solid transparent; transition: all 0.3s; }
.btn:hover { background: var(--primary-light); transform: translateY(-2px); box-shadow: 0 10px 20px rgba(37, 99, 235, 0.3); }

.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 30px; margin: 60px 0; }
.card { background: var(--bg-card); padding: 40px; border-radius: 12px; border: 1px solid var(--border); transition: all 0.3s; }
.card:hover { border-color: var(--primary); transform: translateY(-5px); box-shadow: 0 20px 40px rgba(0,0,0,0.4); }
.card h3 { font-size: 1.5rem; margin-bottom: 16px; color: var(--text-main); }
.card p { color: var(--text-muted); font-size: 1.05rem; }

/* 宽体内容区 (左右图文) */
.content-section { padding: 100px 20px; }
.content-flex { display: flex; gap: 60px; align-items: center; flex-wrap: wrap; }
.content-flex > div { flex: 1; min-width: 300px; }
.content-title { font-size: 2.5rem; font-weight: 800; margin-bottom: 24px; }

/* 页脚 */
.footer { background: #000; border-top: 1px solid var(--border); padding: 80px 20px 30px; margin-top: 60px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; max-width: 1200px; margin: 0 auto; border-bottom: 1px solid var(--border); padding-bottom: 60px; }
.footer h4 { color: #fff; font-size: 1.1rem; margin-bottom: 20px; font-weight: 600; }
.footer ul li { margin-bottom: 12px; font-size: 0.95rem; }
.email-link { color: var(--primary-light); font-weight: 600; }
.footer-bottom { text-align: center; padding-top: 30px; font-size: 0.85rem; color: #52525b; }

/* 手机端智能适配 */
@media (max-width: 768px) {
    .nav ul { display: none; /* 移动端精简菜单 */ }
    .page-hero h1 { font-size: 2.5rem; }
    .footer-grid { grid-template-columns: 1fr; gap: 40px; text-align: center; }
}