* { margin: 0; padding: 0; box-sizing: border-box; }
:root {
    --primary-color: #00f2fe;
    --secondary-color: #4facfe;
    --dark-bg: #0b0f19;
    --card-bg: rgba(255, 255, 255, 0.05);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--dark-bg);
    color: #ffffff;
    line-height: 1.8;
    font-size: 16px;
    overflow-x: hidden;
    padding-top: 80px;
}

a { text-decoration: none; color: inherit; }
.section-title { text-align: center; font-size: 36px; margin-bottom: 40px; color: var(--primary-color); }

/* 顶部固定导航栏 */
.desktop-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 5%;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 80px;
    z-index: 1000;
    backdrop-filter: blur(10px);
    background: rgba(11, 15, 25, 0.9);
    border-bottom: 1px solid rgba(255,255,255,0.05);
}

.logo { font-size: 24px; font-weight: bold; letter-spacing: 2px; color: var(--primary-color); }

.nav-links a {
    margin-left: 30px;
    font-size: 16px;
    transition: color 0.3s;
}
.nav-links a:hover { color: var(--primary-color); }

/* 手机端汉堡按钮 */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 24px;
    cursor: pointer;
    z-index: 1100;
}
.menu-toggle span {
    display: block;
    width: 100%;
    height: 3px;
    background-color: #fff;
    border-radius: 3px;
    transition: all 0.3s ease;
}

/* 手机端下拉菜单 */
.mobile-dropdown {
    display: none;
    position: fixed;
    top: 80px;
    left: 0;
    width: 100%;
    background: rgba(11, 15, 25, 0.98);
    backdrop-filter: blur(10px);
    flex-direction: column;
    align-items: center;
    padding: 20px 0;
    z-index: 999;
    border-bottom: 1px solid rgba(255,255,255,0.1);
    box-shadow: 0 10px 20px rgba(0,0,0,0.5);
}
.mobile-dropdown a {
    color: #fff;
    font-size: 18px;
    padding: 15px 0;
    width: 100%;
    text-align: center;
    transition: background 0.3s;
}
.mobile-dropdown a:hover {
    background: rgba(0, 242, 254, 0.1);
    color: var(--primary-color);
}

/* 首页视频区 */
.hero {
    height: calc(100vh - 80px);
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    position: relative;
    overflow: hidden;
}
.hero-video {
    position: absolute;
    top: 50%;
    left: 50%;
    min-width: 100%;
    min-height: 100%;
    transform: translate(-50%, -50%);
    z-index: -2;
}
.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.6);
    z-index: -1;
}
.hero-content { z-index: 1; padding: 0 20px; }
.hero h1 {
    font-size: 56px;
    margin-bottom: 20px;
    background: linear-gradient(to right, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.hero p {
    font-size: 20px;
    color: #a0aec0;
    margin-bottom: 40px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}
.cta-btn {
    padding: 15px 40px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    color: #000;
    font-weight: bold;
    border-radius: 50px;
    transition: transform 0.3s, box-shadow 0.3s;
    display: inline-block;
    border: none;
    cursor: pointer;
}
.cta-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(0, 242, 254, 0.3);
}

/* 测评卡片 */
.features { padding: 100px 5%; display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 30px; }
.feature-card {
    background: var(--card-bg);
    padding: 0;
    border-radius: 15px;
    border: 1px solid rgba(255,255,255,0.1);
    transition: transform 0.3s, border-color 0.3s;
    overflow: hidden;
}
.feature-card:hover { transform: translateY(-5px); border-color: var(--primary-color); }
.feature-card img { width: 100%; height: 200px; object-fit: cover; }
.feature-card h3 { font-size: 22px; margin: 15px 20px 10px; color: #fff; }
.feature-card p { color: #a0aec0; font-size: 15px; padding: 0 20px 10px; }
.card-link { display: block; padding: 0 20px 20px; color: var(--primary-color); font-weight: bold; font-size: 14px; }

/* 静态页面通用样式 */
.static-page { max-width: 800px; margin: 50px auto 100px; padding: 0 20px; color: #ccc; }
.static-page h1 { color: var(--primary-color); margin-bottom: 30px; font-size: 40px; }
.static-page h2 { color: #fff; margin: 30px 0 15px; font-size: 24px; }

/* 参数表格 */
.spec-table { width: 100%; border-collapse: collapse; margin-top: 20px; }
.spec-table tr { border-bottom: 1px solid rgba(255,255,255,0.1); }
.spec-table td, .spec-table th { padding: 15px; font-size: 16px; text-align: left; }
.spec-table td:last-child, .spec-table th:last-child { color: #00f2fe; font-weight: bold; text-align: right; }

/* 页脚 */
.site-footer {
    padding: 60px 5%;
    text-align: center;
    border-top: 1px solid rgba(255,255,255,0.1);
    margin-top: 50px;
}
.footer-links { margin-bottom: 20px; }
.footer-links a { margin: 0 15px; color: #a0aec0; font-size: 14px; transition: color 0.3s; }
.footer-links a:hover { color: var(--primary-color); }
.copyright { color: #666; font-size: 12px; max-width: 800px; margin: 0 auto; }

/* 响应式：手机端适配 */
@media (max-width: 768px) {
    .nav-links { display: none; }
    .menu-toggle { display: flex; }
    .hero h1 { font-size: 32px; }
    .hero p { font-size: 16px; }
    .features { padding: 60px 5%; }
    .section-title { font-size: 28px; }
}