/* ═══════════ 知汇域官网 — 纯白高端商务风 ═══════════ */
:root {
    --white: #FFFFFF;
    --bg-light: #F8FAFC;
    --primary: #1E40AF;
    --primary-dark: #1E3A8A;
    --primary-light: #3B82F6;
    --accent: #06B6D4;
    --text-dark: #0F172A;
    --text-body: #334155;
    --text-muted: #64748B;
    --border: #E2E8F0;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
    --shadow: 0 4px 24px rgba(0,0,0,0.06);
    --shadow-lg: 0 12px 48px rgba(0,0,0,0.08);
    --radius: 12px;
    --radius-sm: 8px;
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: "Microsoft YaHei", "PingFang SC", -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--white);
    color: var(--text-body);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.section { padding: 80px 0; }
.bg-light { background: var(--bg-light); }
.section-title { font-size: 32px; font-weight: 700; color: var(--text-dark); text-align: center; margin-bottom: 12px; letter-spacing: -0.5px; }
.section-desc { text-align: center; color: var(--text-muted); font-size: 16px; margin-bottom: 48px; max-width: 600px; margin-left: auto; margin-right: auto; }

/* ═══════════ Navigation ═══════════ */
.nav { position: fixed; top: 0; left: 0; right: 0; z-index: 100; background: rgba(255,255,255,0.95); backdrop-filter: blur(12px); border-bottom: 1px solid var(--border); transition: var(--transition); }
.nav.scrolled { box-shadow: var(--shadow); }
.nav-inner { max-width: 1200px; margin: 0 auto; padding: 0 16px; display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { display: flex; align-items: center; gap: 6px; text-decoration: none; color: var(--text-dark); flex-shrink: 0; }
.logo-icon { font-size: 24px; }
.logo-text { font-size: 18px; font-weight: 700; letter-spacing: 0.5px; color: var(--primary); }
.logo-sub { font-size: 10px; color: var(--text-muted); margin-left: 2px; padding-top: 7px; white-space: nowrap; }
.nav-links { display: flex; gap: 2px; flex-shrink: 0; }
.nav-link { padding: 6px 10px; text-decoration: none; color: var(--text-body); font-size: 13px; border-radius: var(--radius-sm); transition: var(--transition); font-weight: 500; white-space: nowrap; }
.nav-link:hover, .nav-link.active { background: var(--primary); color: var(--white); }
.nav-contact { display: flex; align-items: center; gap: 8px; font-size: 11px; color: var(--text-muted); white-space: nowrap; flex-shrink: 0; }
.nav-contact a { color: var(--primary); text-decoration: none; font-weight: 600; }
.nav-contact a:hover { text-decoration: underline; }
.nav-contact .contact-divider { width: 1px; height: 14px; background: var(--border); }
.menu-btn { display: none; background: none; border: none; font-size: 24px; cursor: pointer; color: var(--text-dark); }

/* ═══════════ Hero ═══════════ */
.hero { padding: 140px 24px 80px; text-align: center; background: linear-gradient(180deg, #EFF6FF 0%, var(--white) 100%); }
.hero-title { font-size: 44px; font-weight: 700; color: var(--text-dark); line-height: 1.3; margin-bottom: 16px; letter-spacing: -1px; }
.hero-sub { font-size: 18px; color: var(--text-muted); max-width: 700px; margin: 0 auto 32px; line-height: 1.6; }
.hero-btns { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; margin-bottom: 48px; }
.hero-visual { max-width: 800px; margin: 0 auto; }
.hero-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: 12px; }
.hero-card { background: var(--white); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px 12px; text-align: center; transition: var(--transition); box-shadow: var(--shadow-sm); }
.hero-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--primary-light); }
.hero-card span { font-size: 32px; display: block; margin-bottom: 8px; }
.hero-card p { font-size: 13px; color: var(--text-body); font-weight: 500; }

/* ═══════════ Buttons ═══════════ */
.btn { display: inline-block; padding: 14px 32px; border-radius: var(--radius-sm); font-size: 15px; font-weight: 600; text-decoration: none; cursor: pointer; transition: var(--transition); border: 2px solid transparent; }
.btn-primary { background: var(--primary); color: var(--white); }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-1px); box-shadow: var(--shadow); }
.btn-outline { border-color: var(--primary); color: var(--primary); background: transparent; }
.btn-outline:hover { background: var(--primary); color: var(--white); transform: translateY(-1px); }
.btn-sm { padding: 10px 20px; font-size: 13px; }
.btn-disabled { display: inline-block; padding: 14px 32px; border-radius: var(--radius-sm); font-size: 15px; font-weight: 600; text-decoration: none; background: #CBD5E1; color: #94A3B8; border: 2px solid #CBD5E1; opacity: 0.7; }

/* ═══════════ Architecture ═══════════ */
.arch-diagram { max-width: 700px; margin: 0 auto; }
.arch-layer { border: 1px solid var(--border); border-radius: var(--radius); padding: 20px 24px; margin-bottom: 0; background: var(--white); box-shadow: var(--shadow-sm); }
.layer-label { font-weight: 700; color: var(--primary); font-size: 14px; margin-bottom: 8px; }
.layer-items { display: flex; flex-wrap: wrap; gap: 8px; }
.layer-items span { background: var(--bg-light); padding: 4px 12px; border-radius: 20px; font-size: 12px; color: var(--text-body); border: 1px solid var(--border); }
.arch-arrow { text-align: center; color: var(--primary-light); font-size: 13px; padding: 8px 0; font-weight: 500; }

/* ═══════════ Feature Grid ═══════════ */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.feature-card { background: var(--white); border: 1px solid var(--border); border-radius: var(--radius); padding: 32px 24px; transition: var(--transition); box-shadow: var(--shadow-sm); }
.feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--primary-light); }
.feature-icon { font-size: 40px; margin-bottom: 16px; }
.feature-card h3 { font-size: 17px; font-weight: 700; color: var(--text-dark); margin-bottom: 8px; }
.feature-card p { font-size: 14px; color: var(--text-muted); line-height: 1.6; }

/* ═══════════ Advantages ═══════════ */
.adv-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.adv-item { background: var(--white); border: 1px solid var(--border); border-radius: var(--radius); padding: 28px; box-shadow: var(--shadow-sm); transition: var(--transition); }
.adv-item:hover { box-shadow: var(--shadow); }
.adv-num { font-size: 36px; font-weight: 800; color: var(--primary); opacity: 0.15; display: block; margin-bottom: -28px; }
.adv-item h4 { font-size: 18px; font-weight: 700; color: var(--text-dark); margin-bottom: 8px; }
.adv-item p { color: var(--text-muted); font-size: 14px; }

/* ═══════════ Scenarios ═══════════ */
.scene-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.scene-card { background: var(--white); border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 24px; transition: var(--transition); box-shadow: var(--shadow-sm); }
.scene-card:hover { transform: translateY(-2px); box-shadow: var(--shadow); }
.scene-card h4 { font-size: 16px; font-weight: 700; color: var(--text-dark); margin-bottom: 8px; }
.scene-card p { font-size: 13px; color: var(--text-muted); }

/* ═══════════ Feature Page (Tree + Detail) ═══════════ */
.feature-page { padding-top: 88px; min-height: 100vh; display: flex; }
.feature-sidebar { width: 280px; background: var(--bg-light); border-right: 1px solid var(--border); padding: 24px 16px; position: fixed; top: 64px; bottom: 0; overflow-y: auto; scrollbar-width: thin; }
.feature-sidebar h3 { font-size: 16px; color: var(--text-dark); margin-bottom: 16px; padding-left: 8px; }
.tree-node { user-select: none; }
.tree-parent { display: flex; align-items: center; gap: 6px; padding: 10px 8px; cursor: pointer; border-radius: var(--radius-sm); transition: var(--transition); font-weight: 600; color: var(--text-dark); font-size: 14px; }
.tree-parent:hover { background: var(--white); color: var(--primary); }
.tree-parent.active { background: var(--primary); color: var(--white); }
.tree-arrow { font-size: 10px; transition: transform 0.2s; width: 14px; text-align: center; }
.tree-arrow.expanded { transform: rotate(90deg); }
.tree-children { overflow: hidden; transition: max-height 0.3s ease; }
.tree-child { display: block; padding: 8px 8px 8px 36px; cursor: pointer; border-radius: var(--radius-sm); font-size: 13px; color: var(--text-body); transition: var(--transition); text-decoration: none; }
.tree-child:hover { background: var(--white); color: var(--primary); }
.tree-child.active { background: rgba(30,64,175,0.08); color: var(--primary); font-weight: 600; }
.feature-main { margin-left: 280px; flex: 1; padding: 40px 48px; }
.feature-detail h2 { font-size: 28px; color: var(--text-dark); margin-bottom: 8px; }
.feature-detail .module-tag { display: inline-block; background: rgba(30,64,175,0.08); color: var(--primary); padding: 4px 12px; border-radius: 20px; font-size: 12px; font-weight: 600; margin-bottom: 20px; }
.feature-detail p { font-size: 15px; color: var(--text-body); line-height: 1.8; margin-bottom: 16px; }
.feature-detail .highlight-box { background: var(--bg-light); border-left: 4px solid var(--primary); padding: 20px 24px; border-radius: 0 var(--radius-sm) var(--radius-sm) 0; margin: 24px 0; }
.feature-detail .highlight-box h4 { color: var(--primary); margin-bottom: 8px; font-size: 15px; }
.feature-detail .highlight-box ul { padding-left: 18px; }
.feature-detail .highlight-box li { color: var(--text-body); margin-bottom: 4px; font-size: 14px; }

/* ═══════════ Trial Page ═══════════ */
.trial-page { padding-top: 100px; min-height: 100vh; }
.trial-card { max-width: 560px; margin: 0 auto; background: var(--white); border: 1px solid var(--border); border-radius: var(--radius); padding: 48px; box-shadow: var(--shadow); }
.trial-card h2 { font-size: 24px; text-align: center; margin-bottom: 8px; color: var(--text-dark); }
.trial-card .subtitle { text-align: center; color: var(--text-muted); margin-bottom: 32px; font-size: 14px; }
.form-group { margin-bottom: 20px; }
.form-group label { display: block; font-size: 13px; font-weight: 600; color: var(--text-dark); margin-bottom: 6px; }
.form-group input, .form-group textarea, .form-group select { width: 100%; padding: 12px 16px; border: 1px solid var(--border); border-radius: var(--radius-sm); font-size: 14px; font-family: inherit; transition: var(--transition); background: var(--white); }
.form-group input:focus, .form-group textarea:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(30,64,175,0.1); }
.form-group textarea { resize: vertical; min-height: 80px; }
.form-row { display: flex; gap: 12px; }
.form-row .form-group { flex: 1; }
.form-group .hint { font-size: 12px; color: var(--text-muted); margin-top: 4px; }
.private-notice { background: #FFF7ED; border: 1px solid #FED7AA; border-radius: var(--radius-sm); padding: 20px; text-align: center; color: #C2410C; margin-top: 24px; }
.private-notice h4 { margin-bottom: 8px; }
.success-box { text-align: center; padding: 48px 0; }
.success-box .icon { font-size: 64px; margin-bottom: 16px; }
.success-box h3 { font-size: 22px; color: var(--text-dark); margin-bottom: 8px; }
/* Agreement box */
.agreement-box { border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 16px; margin: 20px 0; background: var(--bg-light); }
.agreement-box h4 { color: var(--primary); font-size: 14px; margin-bottom: 8px; }
.agreement-scroll { max-height: 220px; overflow-y: auto; font-size: 12px; color: var(--text-body); line-height: 1.8; padding-right: 8px; scrollbar-width: thin; scrollbar-color: #CBD5E1 transparent; }
.agreement-scroll p { margin-bottom: 8px; }
.agreement-scroll::-webkit-scrollbar { width: 4px; }
.agreement-scroll::-webkit-scrollbar-thumb { background: #CBD5E1; border-radius: 2px; }

/* ═══════════ Modal Overlay ═══════════ */
.modal-overlay { display: none; position: fixed; inset: 0; z-index: 9999; background: rgba(15,23,42,0.6); backdrop-filter: blur(4px); align-items: center; justify-content: center; }
.modal-box { background: var(--white); border-radius: var(--radius); max-width: 600px; width: 90%; max-height: 80vh; display: flex; flex-direction: column; box-shadow: var(--shadow-lg); }
.modal-header { display: flex; align-items: center; justify-content: space-between; padding: 20px 24px 16px; border-bottom: 1px solid var(--border); }
.modal-header h3 { font-size: 17px; color: var(--text-dark); }
.modal-close { background: none; border: none; font-size: 24px; cursor: pointer; color: var(--text-muted); padding: 0; line-height: 1; transition: var(--transition); }
.modal-close:hover { color: var(--text-dark); }
.modal-body { padding: 20px 24px; overflow-y: auto; flex: 1; font-size: 14px; color: var(--text-body); line-height: 1.8; }
.modal-body p { margin-bottom: 12px; }
.modal-footer { display: flex; justify-content: flex-end; gap: 12px; padding: 16px 24px 20px; border-top: 1px solid var(--border); }

/* ═══════════ Footer ═══════════ */
.footer { background: var(--text-dark); color: #CBD5E1; padding: 48px 0 24px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 40px; margin-bottom: 32px; }
.footer-col h4 { color: var(--white); font-size: 15px; margin-bottom: 12px; }
.footer-col p, .footer-col a { font-size: 13px; line-height: 2; color: #94A3B8; text-decoration: none; display: block; }
.footer-col a:hover { color: var(--white); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.08); padding-top: 20px; text-align: center; font-size: 13px; color: #64748B; }

/* ═══════════ Comparison Table ═══════════ */
.compare-table-wrapper { overflow-x: auto; }
.compare-table { width: 100%; border-collapse: collapse; font-size: 14px; border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; }
.compare-table thead { background: var(--primary); color: var(--white); }
.compare-table th { padding: 14px 16px; text-align: left; font-weight: 600; font-size: 14px; }
.compare-table th.col-work { background: #1E40AF; }
.compare-table th.col-life { background: #3B82F6; }
.compare-table td { padding: 12px 16px; border-bottom: 1px solid var(--border); vertical-align: top; line-height: 1.7; }
.compare-table tbody tr:hover { background: #F0F7FF; }
.compare-table tbody tr:last-child td { border-bottom: none; }
.compare-table .module-name { font-weight: 700; color: var(--text-dark); white-space: nowrap; }
.compare-table .col-work { background: rgba(30,64,175,0.02); border-left: 1px solid var(--border); }
.compare-table .col-life { background: rgba(59,130,246,0.02); border-left: 1px solid var(--border); }
.compare-table .extra-tag { display: block; font-size: 12px; color: var(--text-muted); margin-top: 4px; }

/* ═══════════ Animations ═══════════ */
.fade-in { animation: fadeIn 0.6s ease-out; }
.fade-in-delay { animation: fadeIn 0.6s ease-out 0.2s both; }
.fade-in-delay-2 { animation: fadeIn 0.6s ease-out 0.4s both; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }

/* ═══════════ Responsive ═══════════ */
@media (max-width: 1024px) {
    .hero-grid { grid-template-columns: repeat(3, 1fr); }
    .feature-grid, .scene-grid { grid-template-columns: repeat(2, 1fr); }
    .feature-sidebar { width: 240px; }
    .feature-main { margin-left: 240px; padding: 32px 24px; }
}
@media (max-width: 768px) {
    .hero-title { font-size: 28px; }
    .hero-grid { grid-template-columns: repeat(2, 1fr); }
    .feature-grid, .scene-grid, .adv-grid { grid-template-columns: 1fr; }
    .feature-page { flex-direction: column; }
    .feature-sidebar { position: relative; width: 100%; top: 0; border-right: none; border-bottom: 1px solid var(--border); padding: 16px; }
    .feature-main { margin-left: 0; padding: 24px 16px; }
    .footer-grid { grid-template-columns: 1fr; gap: 24px; }
    .nav-links { display: none; position: absolute; top: 64px; left: 0; right: 0; background: var(--white); flex-direction: column; border-bottom: 1px solid var(--border); padding: 8px 16px; box-shadow: var(--shadow); }
    .nav-links.open { display: flex; }
    .menu-btn { display: block; }
    .hero-btns { flex-direction: column; align-items: center; }
    .trial-card { padding: 24px; margin: 0 16px; }
    .form-row { flex-direction: column; }
}