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

:root {
    --primary-color: #2563eb;
    --secondary-color: #7c3aed;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-white: #ffffff;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --gradient-primary: linear-gradient(135deg, #2563eb 0%, #7c3aed 100%);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-white);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    transition: box-shadow 0.3s ease;
}

.navbar.scrolled {
    box-shadow: var(--shadow-md);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 20px;
}

.logo h2 {
    font-size: 1.5rem;
    font-weight: 700;
    background: var(--gradient-primary);
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.nav-menu {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.nav-link {
    position: relative;
    color: var(--text-dark);
    font-weight: 500;
    text-decoration: none;
    transition: color 0.3s ease;
}

.nav-link::after {
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    content: '';
    background: var(--gradient-primary);
    transition: width 0.3s ease;
}

.nav-link:hover {
    color: var(--primary-color);
}

.nav-link:hover::after {
    width: 100%;
}

.hamburger {
    display: none;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    border-radius: 3px;
    background: var(--text-dark);
    transition: all 0.3s ease;
}

.section-header {
    margin-bottom: 3rem;
    text-align: center;
}

.section-title {
    margin-bottom: 0.5rem;
    color: var(--text-dark);
    font-size: 2.5rem;
    font-weight: 700;
}

.section-subtitle {
    color: var(--text-light);
    font-size: 1.125rem;
}

.footer {
    padding: 3rem 0 1.5rem;
    color: white;
    background: var(--text-dark);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-brand h3 {
    margin-bottom: 0.5rem;
    font-size: 1.5rem;
}

.footer-brand p,
.footer-links a,
.footer-products a {
    color: rgba(255, 255, 255, 0.7);
}

.footer-links h4,
.footer-products h4 {
    margin-bottom: 1rem;
    font-size: 1.125rem;
}

.footer-links ul,
.footer-products ul {
    list-style: none;
}

.footer-links li,
.footer-products li {
    margin-bottom: 0.5rem;
}

.footer-links a,
.footer-products a {
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-links a:hover,
.footer-products a:hover {
    color: white;
}

.footer-bottom {
    padding-top: 2rem;
    text-align: center;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom p,
.footer-bottom .beian a {
    color: rgba(255, 255, 255, 0.6);
}

.footer-bottom .beian {
    margin-top: 0.5rem;
    font-size: 0.875rem;
}

.footer-bottom .beian a {
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-bottom .beian a:hover {
    color: rgba(255, 255, 255, 0.9);
    text-decoration: underline;
}

@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        flex-direction: column;
        width: 100%;
        padding: 2rem 0;
        text-align: center;
        background-color: white;
        box-shadow: var(--shadow-md);
        transition: left 0.3s ease;
    }

    .nav-menu.active {
        left: 0;
    }

    .section-title {
        font-size: 2rem;
    }
}

@media (max-width: 480px) {
    .section-title {
        font-size: 1.75rem;
    }
}