:root {
    --primary: #1A56DB; /* 商务办公蓝 */
    --primary-hover: #1E40AF;
    --secondary: #0F172A; /* 深岩灰 */
    --bg-light: #F8FAFC;
    --bg-white: #FFFFFF;
    --text-main: #1E293B;
    --text-muted: #64748B;
    --border-color: #E2E8F0;
    --ai-gradient: linear-gradient(135deg, #1A56DB 0%, #7C3AED 100%);
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -1px rgba(0,0,0,0.06);
    --shadow-lg: 0 10px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
body { 
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color: var(--text-main); 
    background-color: var(--bg-white);
    line-height: 1.6;
}
a { text-decoration: none; color: inherit; transition: 0.2s; }
ul { list-style: none; }
img { max-width: 100%; display: block; border-radius: 8px; }

/* 导航 */
header {
    background: var(--bg-white); border-bottom: 1px solid var(--border-color);
    position: sticky; top: 0; z-index: 1000; box-shadow: var(--shadow-sm);
}
.nav-inner { max-width: 1200px; margin: 0 auto; display: flex; justify-content: space-between; align-items: center; height: 64px; padding: 0 20px; }
.logo { font-size: 20px; font-weight: 700; color: var(--secondary); display: flex; align-items: center; gap: 8px; }
.logo img { width: 28px; height: 28px; }
.nav-links { display: flex; gap: 32px; }
.nav-links a { font-size: 15px; font-weight: 500; color: var(--text-muted); }
.nav-links a:hover, .nav-links a.active { color: var(--primary); }

.btn {
    display: inline-flex; align-items: center; justify-content: center;
    padding: 10px 24px; border-radius: 6px; font-weight: 600; font-size: 15px;
    cursor: pointer; transition: 0.2s; border: 1px solid transparent;
}
.btn-primary { background: var(--primary); color: #fff; box-shadow: var(--shadow-sm); }
.btn-primary:hover { background: var(--primary-hover); transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn-outline { background: #fff; color: var(--text-main); border: 1px solid var(--border-color); box-shadow: var(--shadow-sm); }
.btn-outline:hover { background: var(--bg-light); border-color: #cbd5e1; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
section { padding: 80px 0; }
.sec-title { font-size: 32px; font-weight: 700; margin-bottom: 16px; text-align: center; color: var(--secondary); }
.sec-desc { font-size: 16px; color: var(--text-muted); text-align: center; margin-bottom: 48px; max-width: 700px; margin-left: auto; margin-right: auto; }

/* Hero区 */
.hero { background: var(--bg-light); padding: 100px 0; overflow: hidden; position: relative; border-bottom: 1px solid var(--border-color); }
.hero::before { content: ''; position: absolute; top: -100px; right: -100px; width: 400px; height: 400px; background: var(--ai-gradient); filter: blur(100px); opacity: 0.1; border-radius: 50%; }
.hero-content { display: flex; align-items: center; gap: 60px; }
.hero-text { flex: 1; }
.badge-ai { display: inline-block; padding: 4px 12px; background: rgba(26,86,219,0.1); color: var(--primary); font-size: 13px; font-weight: 700; border-radius: 20px; margin-bottom: 20px; }
.hero-title { font-size: 48px; font-weight: 800; line-height: 1.2; margin-bottom: 20px; color: var(--secondary); letter-spacing: -0.5px; }
.hero-title span { background: var(--ai-gradient); -webkit-background-clip: text; color: transparent; }
.hero-subtitle { font-size: 20px; font-weight: 600; color: var(--text-main); margin-bottom: 16px; }
.hero-desc { font-size: 16px; color: var(--text-muted); margin-bottom: 32px; }
.hero-btns { display: flex; gap: 16px; }
.hero-img { flex: 1; position: relative; }
.hero-img img { box-shadow: var(--shadow-lg); border: 1px solid var(--border-color); border-radius: 12px; }

/* 核心卖点 */
.feature-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 24px; }
.f-card { background: var(--bg-white); border: 1px solid var(--border-color); padding: 32px 20px; text-align: center; border-radius: 12px; transition: 0.3s; box-shadow: var(--shadow-sm); }
.f-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: var(--primary); }
.f-card img { width: 48px; height: 48px; margin: 0 auto 20px; }
.f-card h3 { font-size: 16px; font-weight: 600; color: var(--secondary); margin-bottom: 8px; }
.f-card p { font-size: 13px; color: var(--text-muted); line-height: 1.5; }

/* 办公详情 */
.detail-list { display: flex; flex-direction: column; gap: 80px; }
.detail-item { display: flex; gap: 60px; align-items: center; }
.detail-item:nth-child(even) { flex-direction: row-reverse; }
.d-text { flex: 1; }
.d-text .ai-tag { font-size: 12px; font-weight: 700; color: #7C3AED; letter-spacing: 1px; text-transform: uppercase; margin-bottom: 10px; display: block; }
.d-text h3 { font-size: 30px; font-weight: 700; margin-bottom: 20px; color: var(--secondary); }
.d-text p { font-size: 16px; color: var(--text-muted); margin-bottom: 24px; line-height: 1.7; }
.d-list { margin-bottom: 24px; }
.d-list li { position: relative; padding-left: 24px; margin-bottom: 12px; font-size: 15px; color: var(--text-main); }
.d-list li::before { content: '✓'; position: absolute; left: 0; color: var(--primary); font-weight: bold; }
.d-img { flex: 1; }
.d-img img { box-shadow: var(--shadow-lg); border: 1px solid var(--border-color); border-radius: 12px; }

/* 浏览器对比 */
.compare-box { background: var(--bg-white); border: 1px solid var(--border-color); border-radius: 12px; overflow: hidden; box-shadow: var(--shadow-sm); }
.compare-table { width: 100%; border-collapse: collapse; text-align: left; }
.compare-table th, .compare-table td { padding: 20px 24px; border-bottom: 1px solid var(--border-color); }
.compare-table th { background: var(--bg-light); font-weight: 600; color: var(--text-muted); font-size: 14px; text-transform: uppercase; }
.compare-table td { font-size: 15px; }
.compare-table .hl { background: rgba(26,86,219,0.03); color: var(--primary); font-weight: 600; border-left: 1px solid rgba(26,86,219,0.1); border-right: 1px solid rgba(26,86,219,0.1); }
.compare-table tr:last-child td { border-bottom: none; }

/* 下载版本 */
.v-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.v-card { background: var(--bg-white); border: 1px solid var(--border-color); padding: 40px 32px; border-radius: 12px; transition: 0.3s; position: relative; }
.v-card:hover { box-shadow: var(--shadow-md); border-color: #cbd5e1; }
.v-card.rec { border: 2px solid var(--primary); box-shadow: var(--shadow-sm); }
.v-card.rec::after { content: '企业优选'; position: absolute; top: -12px; left: 50%; transform: translateX(-50%); background: var(--primary); color: #fff; font-size: 12px; font-weight: 600; padding: 4px 12px; border-radius: 20px; }
.v-card h3 { font-size: 22px; font-weight: 700; margin-bottom: 12px; color: var(--secondary); text-align: center; }
.v-card p { font-size: 14px; color: var(--text-muted); margin-bottom: 32px; text-align: center; height: 42px; }
.v-card .btn { width: 100%; }

/* 数据背书 */
.data-sec { background: var(--secondary); padding: 64px 0; border-radius: 16px; color: #fff; margin-top: 40px; position: relative; overflow: hidden; }
.data-sec::before { content: ''; position: absolute; top: 0; left: 0; right: 0; bottom: 0; background: var(--ai-gradient); opacity: 0.1; }
.data-flex { display: flex; justify-content: space-around; position: relative; z-index: 10; text-align: center; }
.data-item h4 { font-size: 44px; font-weight: 800; margin-bottom: 8px; color: #fff; }
.data-item p { font-size: 15px; color: #94A3B8; font-weight: 500; }

/* FAQ */
.faq-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.faq-box { background: var(--bg-light); border: 1px solid var(--border-color); padding: 24px; border-radius: 8px; }
.faq-box h4 { font-size: 16px; font-weight: 600; margin-bottom: 12px; color: var(--secondary); display: flex; align-items: center; gap: 8px; }
.faq-box h4::before { content: 'Q'; display: inline-flex; align-items: center; justify-content: center; width: 24px; height: 24px; background: rgba(26,86,219,0.1); color: var(--primary); border-radius: 4px; font-size: 13px; }
.faq-box p { font-size: 14px; color: var(--text-muted); line-height: 1.6; padding-left: 32px; }

footer { background: var(--bg-white); border-top: 1px solid var(--border-color); padding: 40px 0; text-align: center; color: var(--text-muted); font-size: 14px; }