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

:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --text: #1f2937;
    --text-light: #6b7280;
    --bg: #ffffff;
    --bg-alt: #f9fafb;
    --border: #e5e7eb;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
    color: var(--text);
    line-height: 1.6;
    background: var(--bg);
}

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

a:hover {
    color: var(--primary-dark);
}

.container {
    max-width: 1120px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
.header {
    position: sticky;
    top: 0;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: saturate(180%) blur(12px);
    -webkit-backdrop-filter: saturate(180%) blur(12px);
    border-bottom: 1px solid var(--border);
    z-index: 10;
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.logo {
    font-size: 18px;
    font-weight: 600;
    color: var(--text);
}

.nav {
    display: flex;
    gap: 32px;
}

.nav a {
    color: var(--text);
    font-size: 14px;
}

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

/* Hero */
.hero {
    padding: 96px 0 80px;
    background: linear-gradient(180deg, #f0f7ff 0%, #ffffff 100%);
    text-align: center;
}

.hero h1 {
    font-size: 44px;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 20px;
    background: linear-gradient(135deg, #1f2937 0%, #2563eb 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    font-size: 18px;
    color: var(--text-light);
    max-width: 640px;
    margin: 0 auto 32px;
}

.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 500;
    transition: all 0.2s;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    color: white;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
}

/* Sections */
.section {
    padding: 80px 0;
}

.section-alt {
    background: var(--bg-alt);
}

.section-title {
    text-align: center;
    font-size: 32px;
    font-weight: 600;
    margin-bottom: 16px;
}

.section-subtitle {
    text-align: center;
    color: var(--text-light);
    margin-bottom: 56px;
    font-size: 16px;
}

/* Features grid */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
}

.card {
    background: white;
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 32px;
    transition: all 0.2s;
}

.card:hover {
    border-color: var(--primary);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
}

.card-icon {
    width: 48px;
    height: 48px;
    border-radius: 10px;
    background: linear-gradient(135deg, #dbeafe, #bfdbfe);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    font-size: 24px;
}

.card h3 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 8px;
}

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

/* About */
.about-content {
    max-width: 760px;
    margin: 0 auto;
    text-align: center;
}

.about-content p {
    color: var(--text-light);
    margin-bottom: 16px;
    font-size: 16px;
}

/* Contact */
.contact-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
    max-width: 800px;
    margin: 0 auto;
}

.contact-item {
    text-align: center;
    padding: 24px;
}

.contact-item .label {
    font-size: 13px;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 8px;
}

.contact-item .value {
    font-size: 16px;
    font-weight: 500;
}

/* Footer */
.footer {
    background: #111827;
    color: #9ca3af;
    padding: 48px 0 32px;
    font-size: 14px;
}

.footer-content {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 24px;
    margin-bottom: 32px;
}

.footer-brand h4 {
    color: white;
    font-size: 16px;
    margin-bottom: 8px;
}

.footer-links a {
    color: #9ca3af;
    margin-left: 24px;
}

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

.footer-bottom {
    border-top: 1px solid #1f2937;
    padding-top: 24px;
    text-align: center;
    font-size: 13px;
}

.footer-bottom a {
    color: #9ca3af;
}

.footer-bottom a:hover {
    color: white;
}

/* Privacy page */
.page {
    padding: 64px 0 80px;
}

.page-title {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 8px;
}

.page-meta {
    color: var(--text-light);
    font-size: 14px;
    margin-bottom: 40px;
    padding-bottom: 24px;
    border-bottom: 1px solid var(--border);
}

.page-content {
    max-width: 820px;
    margin: 0 auto;
}

.page-content h2 {
    font-size: 22px;
    font-weight: 600;
    margin: 40px 0 16px;
    color: var(--text);
}

.page-content h3 {
    font-size: 17px;
    font-weight: 600;
    margin: 24px 0 12px;
}

.page-content p,
.page-content li {
    color: #374151;
    margin-bottom: 12px;
    font-size: 15px;
}

.page-content ul,
.page-content ol {
    padding-left: 24px;
    margin-bottom: 16px;
}

.page-content li {
    margin-bottom: 6px;
}

.page-content strong {
    color: var(--text);
}

@media (max-width: 640px) {
    .hero {
        padding: 64px 0 56px;
    }
    .hero h1 {
        font-size: 32px;
    }
    .hero p {
        font-size: 16px;
    }
    .section {
        padding: 56px 0;
    }
    .section-title {
        font-size: 26px;
    }
    .page-title {
        font-size: 28px;
    }
    .nav {
        gap: 20px;
    }
    .nav a {
        font-size: 13px;
    }
    .footer-content {
        flex-direction: column;
    }
    .footer-links a {
        margin-left: 0;
        margin-right: 20px;
    }
}