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

:root {
    --primary: #0066FF;
    --primary-dark: #0052CC;
    --primary-light: #E8F4FD;
    --secondary: #1a1a2e;
    --text: #333333;
    --text-light: #666666;
    --text-muted: #999999;
    --bg: #ffffff;
    --bg-light: #f8fafc;
    --bg-gray: #f0f4f8;
    --border: #e2e8f0;
    --shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 12px 48px rgba(0, 0, 0, 0.12);
    --radius: 12px;
    --radius-sm: 8px;
    --radius-lg: 20px;
    --transition: all 0.3s ease;
    --font: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', Arial, sans-serif;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font);
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

img {
    max-width: 100%;
    height: auto;
}

ul {
    list-style: none;
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.06);
    transition: var(--transition);
}

.header.scrolled {
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.08);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    font-size: 1.25rem;
    color: var(--secondary);
}

.logo-text {
    color: var(--secondary);
}

.footer {
    background: var(--secondary);
    color: rgba(255, 255, 255, 0.8);
    padding: 64px 0 0;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr;
    gap: 48px;
    padding-bottom: 48px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-brand .logo {
    margin-bottom: 16px;
}

.footer-brand .logo-text {
    color: white;
}

.footer-brand p {
    font-size: 0.875rem;
    line-height: 1.8;
    opacity: 0.7;
}

.footer-links h4,
.footer-contact h4 {
    color: white;
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 20px;
}

.footer-links a {
    display: block;
    font-size: 0.875rem;
    opacity: 0.7;
    padding: 4px 0;
    transition: var(--transition);
}

.footer-links a:hover {
    opacity: 1;
    color: #4d9fff;
    padding-left: 4px;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.875rem;
    opacity: 0.7;
    margin-bottom: 12px;
}

.contact-item svg {
    flex-shrink: 0;
    opacity: 0.6;
}

.footer-bottom {
    padding: 24px 0;
    text-align: center;
}

.footer-bottom p {
    font-size: 0.8125rem;
    opacity: 0.5;
}

@media (max-width: 768px) {
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }
}