/* ===== 基础重置 ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif; color: #1a1a2e; background: #fff; line-height: 1.6; }
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img { max-width: 100%; }

/* ===== CSS变量 ===== */
:root {
    --blue: #2AABEE;
    --blue-dark: #1a8fd1;
    --blue-light: #e8f5fd;
    --dark: #1a1a2e;
    --gray: #6b7280;
    --light: #f8fafc;
    --border: #e5e7eb;
    --radius: 16px;
    --shadow: 0 4px 24px rgba(42,171,238,0.10);
    --shadow-lg: 0 12px 48px rgba(42,171,238,0.18);
}

/* ===== 容器 ===== */
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* ===== 导航栏 ===== */
.navbar {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid transparent;
    transition: all 0.3s;
    padding: 0;
}
.navbar.scrolled { border-bottom-color: var(--border); box-shadow: 0 2px 20px rgba(0,0,0,0.08); }
.nav-flex { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.logo { font-size: 1.4rem; font-weight: 800; color: var(--blue); display: flex; align-items: center; gap: 8px; }
.logo i { font-size: 1.6rem; }
.nav-links { display: flex; align-items: center; gap: 8px; }
.nav-links a { padding: 8px 14px; border-radius: 8px; font-size: 0.92rem; font-weight: 500; color: var(--dark); transition: all 0.2s; }
.nav-links a:hover { color: var(--blue); background: var(--blue-light); }
.btn-nav-download { background: var(--blue) !important; color: #fff !important; border-radius: 10px !important; }
.btn-nav-download:hover { background: var(--blue-dark) !important; color: #fff !important; }
.hamburger { display: none; cursor: pointer; font-size: 1.4rem; color: var(--dark); padding: 8px; }
.mobile-menu { display: none; flex-direction: column; background: #fff; border-top: 1px solid var(--border); padding: 12px 24px 16px; gap: 4px; }
.mobile-menu.active { display: flex; }
.mobile-menu a { padding: 10px 14px; border-radius: 8px; font-weight: 500; color: var(--dark); }
.mobile-menu a:hover { background: var(--blue-light); color: var(--blue); }

/* ===== 按钮 ===== */
.btn-primary {
    display: inline-flex; align-items: center; gap: 8px;
    background: var(--blue); color: #fff;
    padding: 14px 28px; border-radius: 12px;
    font-weight: 700; font-size: 1rem;
    transition: all 0.2s; cursor: pointer; border: none;
    box-shadow: 0 4px 16px rgba(42,171,238,0.35);
}
.btn-primary:hover { background: var(--blue-dark); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(42,171,238,0.45); }
.btn-outline {
    display: inline-flex; align-items: center; gap: 8px;
    background: transparent; color: var(--blue);
    padding: 14px 28px; border-radius: 12px;
    font-weight: 700; font-size: 1rem;
    border: 2px solid var(--blue);
    transition: all 0.2s;
}
.btn-outline:hover { background: var(--blue-light); transform: translateY(-2px); }
.btn-large { padding: 16px 36px; font-size: 1.05rem; border-radius: 14px; }

/* ===== 英雄区 ===== */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 50%, #f0f4ff 100%);
    overflow: hidden;
}
.hero .container { display: flex; align-items: center; gap: 60px; }
.hero-content { flex: 1; }
.hero-badge {
    display: inline-flex; align-items: center; gap: 8px;
    background: rgba(42,171,238,0.12); color: var(--blue);
    padding: 8px 16px; border-radius: 50px;
    font-size: 0.85rem; font-weight: 600; margin-bottom: 24px;
    border: 1px solid rgba(42,171,238,0.25);
}
.hero h1 { font-size: 3.2rem; font-weight: 800; line-height: 1.2; margin-bottom: 20px; color: var(--dark); }
.gradient-text { background: linear-gradient(135deg, #2AABEE, #7C3AED); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.hero-sub { font-size: 1.05rem; color: var(--gray); margin-bottom: 32px; line-height: 1.7; }
.hero-sub em { font-style: italic; opacity: 0.8; }
.hero-btns { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 40px; }
.hero-stats { display: flex; gap: 32px; flex-wrap: wrap; }
.stat-item { display: flex; flex-direction: column; }
.stat-item strong { font-size: 1.4rem; font-weight: 800; color: var(--blue); }
.stat-item span { font-size: 0.8rem; color: var(--gray); }

/* 手机模拟器 */
.hero-image { flex: 0 0 320px; display: flex; justify-content: center; }
.phone-mockup {
    width: 240px; height: 480px;
    background: #1a1a2e; border-radius: 40px;
    padding: 20px 14px;
    box-shadow: 0 24px 80px rgba(26,26,46,0.35), 0 0 0 2px #333;
    position: relative;
}
.phone-screen { background: #0d1117; border-radius: 28px; height: 100%; overflow: hidden; }
.chat-demo { padding: 0; display: flex; flex-direction: column; height: 100%; }
.chat-header-demo {
    background: var(--blue); color: #fff;
    padding: 14px 16px; font-weight: 700; font-size: 0.9rem;
    display: flex; align-items: center; gap: 8px;
}
.chat-msg {
    margin: 8px 12px; padding: 10px 14px;
    border-radius: 18px; font-size: 0.78rem; line-height: 1.5; max-width: 80%;
}
.chat-msg.received { background: #1e2738; color: #e2e8f0; align-self: flex-start; border-bottom-left-radius: 4px; }
.chat-msg.sent { background: var(--blue); color: #fff; align-self: flex-end; border-bottom-right-radius: 4px; margin-left: auto; }

/* ===== 信任背书条 ===== */
.trust-bar { padding: 32px 0; background: #fff; border-bottom: 1px solid var(--border); }
.trust-grid { display: flex; justify-content: space-around; align-items: center; flex-wrap: wrap; gap: 24px; }
.trust-item { display: flex; flex-direction: column; align-items: center; gap: 4px; text-align: center; }
.trust-item i { font-size: 1.4rem; color: var(--blue); margin-bottom: 4px; }
.trust-item strong { font-size: 1.1rem; font-weight: 800; color: var(--dark); }
.trust-item span { font-size: 0.78rem; color: var(--gray); }

/* ===== 快速下载 ===== */
.quick-download { padding: 80px 0; background: var(--light); }
.quick-download h2 { text-align: center; font-size: 2rem; font-weight: 800; margin-bottom: 12px; }
.quick-download p { text-align: center; color: var(--gray); margin-bottom: 48px; }
.platform-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: 16px; }
.platform-card {
    display: flex; flex-direction: column; align-items: center; gap: 8px;
    background: #fff; border: 2px solid var(--border);
    border-radius: var(--radius); padding: 24px 12px;
    transition: all 0.2s; cursor: pointer;
}
.platform-card:hover { border-color: var(--blue); box-shadow: var(--shadow); transform: translateY(-4px); }
.platform-card i { font-size: 2rem; color: var(--blue); }
.platform-card span { font-weight: 700; font-size: 0.9rem; color: var(--dark); }
.platform-card small { font-size: 0.72rem; color: var(--gray); }

/* ===== section标题 ===== */
.section-header { text-align: center; margin-bottom: 56px; }
.section-header h2 { font-size: 2.2rem; font-weight: 800; margin-bottom: 12px; color: var(--dark); }
.section-header p { color: var(--gray); font-size: 1.05rem; }

/* ===== 功能卡片 ===== */
.features { padding: 80px 0; background: #fff; }
.features-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.feature-card {
    background: var(--light); border: 1px solid var(--border);
    border-radius: var(--radius); padding: 28px 24px;
    transition: all 0.2s;
}
.feature-card:hover { border-color: var(--blue); box-shadow: var(--shadow); transform: translateY(-4px); }
.feature-icon { width: 52px; height: 52px; background: var(--blue-light); border-radius: 14px; display: flex; align-items: center; justify-content: center; margin-bottom: 16px; }
.feature-icon i { font-size: 1.3rem; color: var(--blue); }
.feature-card h3 { font-size: 1rem; font-weight: 700; margin-bottom: 10px; color: var(--dark); }
.feature-card p { font-size: 0.87rem; color: var(--gray); line-height: 1.6; }

/* ===== 安全区域 ===== */
.security { padding: 80px 0; background: linear-gradient(135deg, #1a1a2e 0%, #0d1b3e 100%); color: #fff; }
.security-inner { display: flex; align-items: center; gap: 80px; }
.security-text { flex: 1; }
.security-text h2 { font-size: 2.4rem; font-weight: 800; margin-bottom: 32px; line-height: 1.3; }
.security-text h2 span { color: var(--blue); }
.security-list { display: flex; flex-direction: column; gap: 16px; }
.security-list li { display: flex; align-items: flex-start; gap: 12px; font-size: 0.95rem; }
.security-list li i { color: #4ade80; margin-top: 2px; flex-shrink: 0; }
.security-image { flex: 0 0 360px; }
.security-card {
    background: rgba(255,255,255,0.06); border: 1px solid rgba(255,255,255,0.12);
    border-radius: 24px; padding: 36px; text-align: center;
    backdrop-filter: blur(12px);
}
.security-card i.fas.fa-shield-alt { font-size: 3.5rem; color: var(--blue); margin-bottom: 20px; }
.security-card h3 { font-size: 1.3rem; font-weight: 700; margin-bottom: 12px; }
.security-card p { color: rgba(255,255,255,0.7); font-size: 0.9rem; margin-bottom: 24px; }
.security-badges { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; }
.security-badges span {
    display: flex; align-items: center; gap: 6px;
    background: rgba(42,171,238,0.2); color: var(--blue);
    padding: 6px 14px; border-radius: 50px; font-size: 0.82rem; font-weight: 600;
    border: 1px solid rgba(42,171,238,0.3);
}

/* ===== 对比表格 ===== */
.compare { padding: 80px 0; background: var(--light); }
.table-wrap { overflow-x: auto; }
.compare-table { width: 100%; border-collapse: collapse; background: #fff; border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); }
.compare-table th { padding: 18px 20px; font-size: 0.95rem; font-weight: 700; background: #f1f5f9; text-align: center; }
.compare-table th:first-child { text-align: left; }
.compare-table th.highlight { background: var(--blue); color: #fff; }
.compare-table td { padding: 15px 20px; font-size: 0.9rem; border-top: 1px solid var(--border); text-align: center; }
.compare-table td:first-child { text-align: left; font-weight: 500; }
.compare-table td.highlight { background: rgba(42,171,238,0.06); font-weight: 700; color: var(--blue); }
.compare-table .fa-check { color: #22c55e; }
.compare-table .fa-times { color: #ef4444; }
.compare-table tr:hover td { background: #f8fafc; }
.compare-table tr:hover td.highlight { background: rgba(42,171,238,0.10); }

/* ===== 评价 ===== */
.reviews { padding: 80px 0; background: #fff; }
.rating-summary { display: flex; align-items: center; gap: 16px; justify-content: center; margin-top: 20px; }
.big-score { font-size: 3.5rem; font-weight: 800; color: var(--dark); line-height: 1; }
.stars-row { display: flex; gap: 4px; font-size: 1.3rem; color: #f59e0b; }
.rating-count { color: var(--gray); font-size: 0.9rem; }
.reviews-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-top: 48px; }
.review-card { background: var(--light); border: 1px solid var(--border); border-radius: var(--radius); padding: 28px 24px; transition: all 0.2s; }
.review-card:hover { box-shadow: var(--shadow); transform: translateY(-4px); }
.review-stars { color: #f59e0b; margin-bottom: 14px; font-size: 0.9rem; }
.review-text { font-size: 0.9rem; color: #374151; line-height: 1.7; margin-bottom: 20px; }
.review-author { display: flex; align-items: center; gap: 12px; }
.review-avatar { width: 40px; height: 40px; background: var(--blue); color: #fff; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: 1rem; flex-shrink: 0; }
.review-info { display: flex; flex-direction: column; }
.review-info strong { font-size: 0.9rem; color: var(--dark); }
.review-info span { font-size: 0.78rem; color: var(--gray); }

/* ===== FAQ ===== */
.faq { padding: 80px 0; background: var(--light); }
.faq-list { max-width: 800px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
.faq-item { background: #fff; border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; }
.faq-q { display: flex; align-items: center; justify-content: space-between; padding: 20px 24px; cursor: pointer; font-weight: 600; font-size: 0.95rem; color: var(--dark); transition: all 0.2s; }
.faq-q:hover { color: var(--blue); }
.faq-q i { transition: transform 0.3s; color: var(--gray); flex-shrink: 0; }
.faq-item.open .faq-q i { transform: rotate(180deg); color: var(--blue); }
.faq-a { display: none; padding: 0 24px 20px; font-size: 0.9rem; color: var(--gray); line-height: 1.7; border-top: 1px solid var(--border); padding-top: 16px; }
.faq-item.open .faq-a { display: block; }

/* ===== CTA ===== */
.cta { padding: 80px 0; background: linear-gradient(135deg, var(--blue) 0%, #7C3AED 100%); text-align: center; }
.cta h2 { font-size: 2.4rem; font-weight: 800; color: #fff; margin-bottom: 16px; }
.cta p { color: rgba(255,255,255,0.85); font-size: 1.05rem; margin-bottom: 40px; }
.cta-btns { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.cta .btn-primary { background: #fff; color: var(--blue); box-shadow: 0 4px 20px rgba(0,0,0,0.2); }
.cta .btn-primary:hover { background: #f0f9ff; }
.cta .btn-outline { border-color: rgba(255,255,255,0.7); color: #fff; }
.cta .btn-outline:hover { background: rgba(255,255,255,0.15); }

/* ===== 分享浮窗 ===== */
.share-float { position: fixed; bottom: 32px; right: 32px; z-index: 999; display: flex; flex-direction: column; align-items: center; gap: 10px; }
.share-toggle { width: 52px; height: 52px; background: var(--blue); border-radius: 50%; display: flex; align-items: center; justify-content: center; color: #fff; font-size: 1.2rem; cursor: pointer; box-shadow: 0 4px 16px rgba(42,171,238,0.4); transition: all 0.2s; }
.share-toggle:hover { background: var(--blue-dark); transform: scale(1.1); }
.share-btns { display: none; flex-direction: column; gap: 8px; }
.share-btns.active { display: flex; }
.share-btn { width: 44px; height: 44px; border-radius: 50%; display: flex; align-items: center; justify-content: center; color: #fff; font-size: 1rem; transition: all 0.2s; box-shadow: 0 2px 10px rgba(0,0,0,0.2); }
.share-btn:hover { transform: scale(1.15); }
.share-twitter { background: #1DA1F2; }
.share-facebook { background: #1877F2; }
.share-weibo { background: #E6162D; }
.share-tg { background: #2AABEE; }

/* ===== 页脚 ===== */
.footer { background: #111827; color: rgba(255,255,255,0.8); padding: 60px 0 32px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 48px; margin-bottom: 48px; }
.footer-logo { color: var(--blue) !important; font-size: 1.3rem; margin-bottom: 16px; display: inline-flex; }
.footer-col p { font-size: 0.87rem; color: rgba(255,255,255,0.55); line-height: 1.7; margin-top: 12px; }
.footer-col h4 { font-size: 0.95rem; font-weight: 700; color: #fff; margin-bottom: 16px; }
.footer-links { display: flex; flex-direction: column; gap: 10px; }
.footer-links a { font-size: 0.87rem; color: rgba(255,255,255,0.55); transition: color 0.2s; }
.footer-links a:hover { color: var(--blue); }
.social-links { display: flex; gap: 12px; margin-top: 16px; }
.social-links a { width: 36px; height: 36px; background: rgba(255,255,255,0.08); border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 0.9rem; transition: all 0.2s; }
.social-links a:hover { background: var(--blue); color: #fff; }
.copyright { text-align: center; font-size: 0.83rem; color: rgba(255,255,255,0.35); border-top: 1px solid rgba(255,255,255,0.08); padding-top: 24px; margin-bottom: 12px; }
.subdomain-links { text-align: center; font-size: 0.78rem; }
.subdomain-links a { color: rgba(255,255,255,0.3); margin: 0 4px; transition: color 0.2s; }
.subdomain-links a:hover { color: var(--blue); }

/* ===== 下载页 ===== */
.dl-hero { padding: 120px 0 80px; background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 50%, #f0f4ff 100%); }
.dl-hero-inner { display: flex; align-items: center; gap: 60px; }
.dl-hero-text { flex: 1; }
.dl-hero-text h1 { font-size: 2.8rem; font-weight: 800; margin: 20px 0; line-height: 1.2; }
.dl-hero-text p { color: var(--gray); font-size: 1.05rem; margin-bottom: 32px; }
.dl-hero-stats { display: flex; gap: 32px; flex-wrap: wrap; margin-top: 32px; }
.dl-hero-icon { flex: 0 0 240px; display: flex; justify-content: center; }
.dl-icon-wrap { width: 180px; height: 180px; background: linear-gradient(135deg, var(--blue), #7C3AED); border-radius: 40px; display: flex; align-items: center; justify-content: center; box-shadow: var(--shadow-lg); }
.dl-icon-wrap i { font-size: 5rem; color: #fff; }
.download-section { padding: 80px 0; background: #fff; }
.download-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.download-card {
    background: var(--light); border: 2px solid var(--border);
    border-radius: 20px; padding: 32px 28px;
    position: relative; transition: all 0.2s;
}
.download-card:hover { border-color: var(--blue); box-shadow: var(--shadow); transform: translateY(-6px); }
.download-card.featured { border-color: var(--blue); background: linear-gradient(135deg, #f0f9ff, #f8f0ff); }
.dl-platform-icon { font-size: 2.8rem; color: var(--blue); margin-bottom: 16px; }
.download-card h3 { font-size: 1.3rem; font-weight: 800; margin-bottom: 6px; }
.dl-version { font-size: 0.82rem; color: var(--gray); margin-bottom: 20px; }
.dl-features { display: flex; flex-direction: column; gap: 8px; margin-bottom: 24px; }
.dl-features li { display: flex; align-items: center; gap: 8px; font-size: 0.87rem; color: #374151; }
.dl-features li i { color: #22c55e; flex-shrink: 0; }
.btn-download {
    display: flex; align-items: center; justify-content: center; gap: 8px;
    background: var(--blue); color: #fff;
    padding: 13px 20px; border-radius: 12px;
    font-weight: 700; font-size: 0.95rem;
    transition: all 0.2s; width: 100%;
    box-shadow: 0 4px 12px rgba(42,171,238,0.3);
}
.btn-download:hover { background: var(--blue-dark); transform: translateY(-2px); }
.btn-outline-dl { background: transparent; color: var(--blue); border: 2px solid var(--blue); box-shadow: none; }
.btn-outline-dl:hover { background: var(--blue-light); }
.dl-tag { position: absolute; top: 16px; right: 16px; background: var(--blue); color: #fff; padding: 4px 12px; border-radius: 50px; font-size: 0.75rem; font-weight: 700; }
.install-guide { padding: 80px 0; background: var(--light); }
.steps-grid { display: flex; align-items: center; justify-content: center; gap: 0; flex-wrap: wrap; }
.step-card { background: #fff; border: 1px solid var(--border); border-radius: 20px; padding: 36px 28px; text-align: center; flex: 1; min-width: 200px; max-width: 280px; }
.step-num { font-size: 2.5rem; font-weight: 900; color: rgba(42,171,238,0.15); line-height: 1; margin-bottom: 12px; }
.step-icon { width: 60px; height: 60px; background: var(--blue-light); border-radius: 50%; display: flex; align-items: center; justify-content: center; margin: 0 auto 16px; }
.step-icon i { font-size: 1.4rem; color: var(--blue); }
.step-card h3 { font-size: 1rem; font-weight: 700; margin-bottom: 10px; }
.step-card p { font-size: 0.85rem; color: var(--gray); line-height: 1.6; }
.step-arrow { font-size: 1.5rem; color: var(--blue); opacity: 0.4; padding: 0 12px; }

/* ===== 特性页 ===== */
.feat-hero { padding: 120px 0 80px; background: linear-gradient(135deg, #f0f9ff 0%, #f0f4ff 100%); text-align: center; }
.feat-hero h1 { font-size: 3rem; font-weight: 800; margin: 20px 0; line-height: 1.2; }
.feat-hero p { color: var(--gray); font-size: 1.05rem; max-width: 600px; margin: 0 auto 32px; }
.feat-section { padding: 80px 0; background: #fff; }
.feat-section.feat-alt { background: var(--light); }
.feat-block { display: flex; align-items: center; gap: 80px; }
.feat-block-reverse { flex-direction: row-reverse; }
.feat-block-text { flex: 1; }
.feat-tag { display: inline-flex; align-items: center; gap: 8px; background: var(--blue-light); color: var(--blue); padding: 6px 16px; border-radius: 50px; font-size: 0.85rem; font-weight: 600; margin-bottom: 20px; }
.feat-block-text h2 { font-size: 2rem; font-weight: 800; margin-bottom: 16px; line-height: 1.3; }
.feat-block-text p { color: var(--gray); font-size: 0.95rem; line-height: 1.7; margin-bottom: 24px; }
.feat-list { display: flex; flex-direction: column; gap: 12px; }
.feat-list li { display: flex; align-items: flex-start; gap: 10px; font-size: 0.9rem; color: #374151; }
.feat-list li i { color: var(--blue); margin-top: 2px; flex-shrink: 0; }
.feat-block-visual { flex: 0 0 380px; }
.feat-visual-card { border-radius: 24px; padding: 40px 32px; text-align: center; }
.security-visual { background: linear-gradient(135deg, #1a1a2e, #0d1b3e); color: #fff; }
.group-visual { background: linear-gradient(135deg, #eff6ff, #dbeafe); }
.file-visual { background: linear-gradient(135deg, #f0fdf4, #dcfce7); }
.bot-visual { background: linear-gradient(135deg, #faf5ff, #ede9fe); }
.cloud-visual { background: linear-gradient(135deg, #f0f9ff, #e0f2fe); }
.feat-big-icon { font-size: 3.5rem; color: var(--blue); margin-bottom: 20px; display: block; }
.security-visual .feat-big-icon { color: var(--blue); }
.feat-stat-row { display: flex; justify-content: center; gap: 32px; margin-top: 16px; }
.feat-stat { display: flex; flex-direction: column; align-items: center; }
.feat-stat strong { font-size: 1.8rem; font-weight: 800; color: var(--blue); }
.feat-stat span { font-size: 0.8rem; color: var(--gray); }
.feat-badges { display: flex; flex-wrap: wrap; gap: 8px; justify-content: center; margin-top: 16px; }
.feat-badges span { display: flex; align-items: center; gap: 6px; background: rgba(42,171,238,0.15); color: var(--blue); padding: 6px 12px; border-radius: 50px; font-size: 0.8rem; font-weight: 600; }
.bot-demo { background: rgba(255,255,255,0.8); border-radius: 14px; padding: 16px; margin-top: 16px; }
.bot-msg { background: #ede9fe; color: #5b21b6; padding: 10px 14px; border-radius: 12px; font-size: 0.82rem; margin-bottom: 12px; text-align: left; }
.bot-btn-row { display: flex; gap: 8px; margin-bottom: 8px; }
.bot-btn-row span { flex: 1; background: var(--blue); color: #fff; padding: 7px 10px; border-radius: 8px; font-size: 0.78rem; font-weight: 600; text-align: center; }
.device-row { display: flex; justify-content: center; gap: 16px; margin-top: 16px; flex-wrap: wrap; }
.device-item { display: flex; flex-direction: column; align-items: center; gap: 6px; }
.device-item i { font-size: 1.8rem; color: var(--blue); }
.device-item span { font-size: 0.75rem; color: var(--gray); font-weight: 600; }
.feat-summary { padding: 80px 0; background: #fff; }
.summary-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: 16px; }
.summary-item { display: flex; flex-direction: column; align-items: center; gap: 8px; background: var(--light); border: 1px solid var(--border); border-radius: 14px; padding: 20px 12px; transition: all 0.2s; }
.summary-item:hover { border-color: var(--blue); box-shadow: var(--shadow); }
.summary-item i { font-size: 1.5rem; color: var(--blue); }
.summary-item span { font-size: 0.82rem; font-weight: 600; color: var(--dark); text-align: center; }

/* ===== 响应式 ===== */
@media (max-width: 1100px) {
    .features-grid { grid-template-columns: repeat(2, 1fr); }
    .download-grid { grid-template-columns: repeat(2, 1fr); }
    .summary-grid { grid-template-columns: repeat(4, 1fr); }
}
@media (max-width: 900px) {
    .hero .container, .dl-hero-inner, .security-inner { flex-direction: column; gap: 40px; }
    .hero-image, .dl-hero-icon, .security-image { display: none; }
    .hero h1, .dl-hero-text h1 { font-size: 2.2rem; }
    .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
    .platform-grid { grid-template-columns: repeat(3, 1fr); }
    .reviews-grid { grid-template-columns: repeat(2, 1fr); }
    .feat-block, .feat-block-reverse { flex-direction: column; gap: 40px; }
    .feat-block-visual { flex: none; width: 100%; }
    .steps-grid { flex-direction: column; align-items: stretch; }
    .step-arrow { display: none; }
}
@media (max-width: 640px) {
    .nav-links { display: none; }
    .hamburger { display: block; }
    .hero h1, .feat-hero h1 { font-size: 1.8rem; }
    .features-grid { grid-template-columns: 1fr; }
    .download-grid { grid-template-columns: 1fr; }
    .reviews-grid { grid-template-columns: 1fr; }
    .platform-grid { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: 1fr; }
    .trust-grid { gap: 16px; }
    .summary-grid { grid-template-columns: repeat(3, 1fr); }
    .hero-stats, .dl-hero-stats { gap: 16px; }
    .share-float { bottom: 16px; right: 16px; }
}