/* 正式软件下载页，强调安全稳定 CSS */
:root {
    --primary-color: #0055FF; /* 官方科技蓝 */
    --primary-hover: #0044CC;
    --safe-green: #00B365; /* 安全绿 */
    --dark-bg: #0A1627; /* 深邃安全蓝背景 */
    --text-main: #1D2129;
    --text-sub: #4E5969;
    --bg-gray: #F2F3F5;
    --border-color: #E5E6EB;
    --radius: 4px; /* 更硬朗的直角/小圆角 */
    --shadow: 0 4px 10px rgba(0, 0, 0, 0.08);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", Roboto, Arial, sans-serif;
}

body {
    color: var(--text-main);
    line-height: 1.6;
    background-color: #fff;
    -webkit-font-smoothing: antialiased;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.2s;
}

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

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 8px 24px;
    font-size: 14px;
    font-weight: 600;
    border-radius: var(--radius);
    cursor: pointer;
    border: 1px solid transparent;
    transition: all 0.2s;
}

.btn-large {
    padding: 12px 32px;
    font-size: 16px;
}

.btn-block {
    display: flex;
    width: 100%;
}

.btn-primary {
    background-color: var(--primary-color);
    color: #fff;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
}

.btn-outline {
    background-color: transparent;
    border-color: var(--border-color);
    color: var(--text-main);
}

.btn-outline:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.btn-outline-light {
    background-color: transparent;
    border-color: rgba(255,255,255,0.4);
    color: #fff;
}

.btn-outline-light:hover {
    background-color: rgba(255,255,255,0.1);
    border-color: #fff;
}

.btn .icon {
    margin-right: 8px;
}

/* Navbar */
.navbar {
    position: sticky;
    top: 0;
    background-color: #fff;
    border-bottom: 1px solid var(--border-color);
    z-index: 100;
}

.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-icon {
    width: 28px;
    height: 28px;
    background-color: var(--primary-color);
    border-radius: 4px;
}

.logo-text {
    font-size: 20px;
    font-weight: 700;
    color: var(--text-main);
    display: flex;
    align-items: center;
    gap: 8px;
}

.badge-secure {
    font-size: 12px;
    background-color: var(--safe-green);
    color: #fff;
    padding: 2px 6px;
    border-radius: 2px;
    font-weight: 500;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 32px;
}

.nav-menu a {
    font-size: 15px;
    color: var(--text-main);
    font-weight: 500;
}

.nav-menu a:hover, .nav-menu a.active {
    color: var(--primary-color);
}

/* Hero Section */
.hero-section {
    background-color: var(--dark-bg);
    color: #fff;
    padding: 80px 0;
    overflow: hidden;
}

.page-hero {
    padding: 60px 0;
}

.hero-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.security-cert {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background-color: rgba(0, 179, 101, 0.15);
    color: var(--safe-green);
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 24px;
    border: 1px solid rgba(0, 179, 101, 0.3);
}

.hero-text h1 {
    font-size: 46px;
    line-height: 1.2;
    margin-bottom: 24px;
    font-weight: 700;
}

.hero-text p {
    font-size: 16px;
    color: #A9B2C2;
    margin-bottom: 40px;
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    gap: 16px;
    margin-bottom: 24px;
}

.hero-meta {
    display: flex;
    gap: 20px;
    font-size: 13px;
    color: #86909C;
}

.hero-meta span {
    display: flex;
    align-items: center;
}

.main-img {
    width: 100%;
    border-radius: 8px;
    box-shadow: 0 24px 48px rgba(0,0,0,0.4);
    border: 1px solid rgba(255,255,255,0.1);
}

/* Data Section */
.data-section {
    background-color: #fff;
    padding: 40px 0;
    border-bottom: 1px solid var(--border-color);
}

.data-wrap {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    text-align: center;
}

.data-number {
    font-size: 32px;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 8px;
}

.data-label {
    font-size: 14px;
    color: var(--text-sub);
}

/* Features */
.features-section {
    padding: 80px 0;
    background-color: var(--bg-gray);
}

.section-head {
    text-align: center;
    margin-bottom: 60px;
}

.section-head h2 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 16px;
}

.section-head p {
    font-size: 16px;
    color: var(--text-sub);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background-color: #fff;
    padding: 32px 24px;
    border-radius: var(--radius);
    border: 1px solid var(--border-color);
    transition: box-shadow 0.3s;
}

.feature-card:hover {
    box-shadow: var(--shadow);
    border-color: #C9CDD4;
}

.f-icon {
    font-size: 32px;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 18px;
    margin-bottom: 12px;
    font-weight: 600;
}

.feature-card p {
    color: var(--text-sub);
    font-size: 14px;
}

/* Solutions */
.solutions-section {
    padding: 80px 0;
    background-color: #fff;
}

.solutions-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.solution-card {
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    overflow: hidden;
}

.solution-card img {
    width: 100%;
    height: 180px;
    object-fit: cover;
    border-bottom: 1px solid var(--border-color);
}

.s-info {
    padding: 24px;
}

.s-info h3 {
    font-size: 18px;
    margin-bottom: 12px;
}

.s-info p {
    font-size: 14px;
    color: var(--text-sub);
}

/* Download Page */
.download-section {
    padding: 80px 0;
    background-color: var(--bg-gray);
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.download-card {
    background-color: #fff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 40px 32px;
    text-align: center;
}

.d-icon {
    font-size: 48px;
    margin-bottom: 24px;
}

.download-card h3 {
    font-size: 20px;
    margin-bottom: 16px;
}

.download-card p {
    color: var(--text-sub);
    font-size: 14px;
    margin-bottom: 16px;
    min-height: 42px;
}

.d-meta {
    font-size: 12px;
    color: #86909C;
    background: #F2F3F5;
    padding: 4px 8px;
    border-radius: 2px;
    margin-bottom: 24px;
    display: inline-block;
}

/* FAQ Section */
.faq-section {
    padding: 80px 0;
    background-color: var(--bg-gray);
}

.faq-wrap {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background-color: #fff;
    border: 1px solid var(--border-color);
    padding: 24px;
    border-radius: var(--radius);
    margin-bottom: 16px;
}

.faq-item h3 {
    font-size: 16px;
    margin-bottom: 12px;
    color: var(--text-main);
}

.faq-item p {
    font-size: 14px;
    color: var(--text-sub);
}

/* CTA */
.cta-section {
    background-color: var(--bg-gray);
    padding: 60px 0 80px;
}

.cta-content {
    background-color: var(--primary-color);
    color: #fff;
    padding: 60px;
    border-radius: 8px;
    text-align: center;
    background-image: url('data:image/svg+xml;utf8,<svg width="100%" height="100%" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grid" width="40" height="40" patternUnits="userSpaceOnUse"><path d="M 40 0 L 0 0 0 40" fill="none" stroke="rgba(255,255,255,0.1)" stroke-width="1"/></pattern></defs><rect width="100%" height="100%" fill="url(%23grid)" /></svg>');
}

.cta-content h2 {
    font-size: 32px;
    margin-bottom: 16px;
}

.cta-content p {
    font-size: 16px;
    opacity: 0.9;
    margin-bottom: 32px;
}

.cta-buttons {
    display: flex;
    justify-content: center;
    gap: 16px;
}

.cta-buttons .btn-primary {
    background-color: #fff;
    color: var(--primary-color);
}

.cta-buttons .btn-primary:hover {
    background-color: #F2F3F5;
}

/* Footer */
.footer {
    background-color: #fff;
    padding: 60px 0 24px;
    border-top: 1px solid var(--border-color);
}

.footer-top {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-brand p {
    margin-top: 12px;
    font-size: 13px;
    color: var(--text-sub);
}

.security-trust {
    margin-top: 16px;
    display: flex;
    gap: 12px;
    font-size: 12px;
    color: var(--safe-green);
}

.footer-links h4 {
    font-size: 15px;
    margin-bottom: 20px;
}

.footer-links a {
    display: block;
    color: var(--text-sub);
    font-size: 14px;
    margin-bottom: 12px;
}

.footer-links a:hover {
    color: var(--primary-color);
}

.footer-bottom {
    border-top: 1px solid var(--border-color);
    padding-top: 24px;
    text-align: center;
    font-size: 13px;
    color: #86909C;
}

@media (max-width: 900px) {
    .hero-grid, .data-wrap, .features-grid, .solutions-grid, .download-grid, .footer-top {
        grid-template-columns: 1fr;
    }
    .nav-menu { display: none; }
    .hero-actions { flex-direction: column; }
    .hero-meta { flex-direction: column; gap: 8px; }
    .cta-buttons { flex-direction: column; }
}