:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --accent: #06b6d4;
    --dark: #0f172a;
    --light: #f8fafc;
    --gray: #64748b;
    --white: #ffffff;
    --gradient: linear-gradient(135deg, #6366f1 0%, #06b6d4 100%);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--dark);
    background: var(--white);
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

/* 导航 */
.navbar {
    background: rgba(255,255,255,0.9);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid #e2e8f0;
    position: sticky;
    top: 0;
    z-index: 100;
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-decoration: none;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 28px;
}

.nav-links a {
    text-decoration: none;
    color: var(--dark);
    font-weight: 500;
    font-size: 0.95rem;
    transition: color 0.2s;
}

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

/* Hero */
.hero {
    background: var(--dark);
    color: var(--white);
    padding: 100px 0;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(99,102,241,0.15) 0%, transparent 70%);
    pointer-events: none;
}

.hero-badge {
    display: inline-block;
    background: rgba(99,102,241,0.2);
    color: var(--accent);
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 20px;
    border: 1px solid rgba(99,102,241,0.3);
}

.hero h1 {
    font-size: 3.2rem;
    font-weight: 800;
    margin-bottom: 16px;
    line-height: 1.2;
    position: relative;
}

.hero .highlight {
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    font-size: 1.25rem;
    color: #94a3b8;
    margin-bottom: 36px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.btn-primary {
    display: inline-block;
    background: var(--gradient);
    color: var(--white);
    padding: 14px 36px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: transform 0.2s, box-shadow 0.2s;
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(99,102,241,0.3);
}

/* 什么是 GEO */
.what-is-geo {
    padding: 80px 0;
    background: var(--light);
}

.section-desc {
    text-align: center;
    color: var(--gray);
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 auto 48px;
}

.comparison {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 24px;
    align-items: center;
}

.compare-card {
    background: var(--white);
    border-radius: 16px;
    padding: 32px;
    border: 1px solid #e2e8f0;
}

.compare-card.old {
    opacity: 0.8;
}

.compare-card.new {
    border-color: var(--primary);
    box-shadow: 0 4px 20px rgba(99,102,241,0.1);
}

.compare-card h3 {
    margin-bottom: 16px;
    font-size: 1.2rem;
}

.compare-card ul {
    list-style: none;
}

.compare-card li {
    padding: 8px 0;
    color: var(--gray);
    font-size: 0.95rem;
}

.compare-arrow {
    font-size: 2rem;
    color: var(--primary);
    font-weight: bold;
}

/* 服务 */
.services {
    padding: 80px 0;
}

.services h2, .methodology h2, .cases h2, .platforms h2, .contact h2 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 48px;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
}

.card {
    background: var(--white);
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    padding: 32px;
    transition: all 0.3s;
}

.card:hover {
    box-shadow: 0 10px 40px rgba(0,0,0,0.08);
    transform: translateY(-4px);
    border-color: var(--primary);
}

.icon {
    font-size: 2rem;
    margin-bottom: 16px;
}

.card h3 {
    margin-bottom: 10px;
    color: var(--dark);
    font-size: 1.1rem;
}

.card p {
    color: var(--gray);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* 方法论 */
.methodology {
    padding: 80px 0;
    background: var(--light);
}

.steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 32px;
}

.step {
    background: var(--white);
    padding: 32px;
    border-radius: 12px;
    border: 1px solid #e2e8f0;
}

.step-num {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--primary);
    opacity: 0.3;
    margin-bottom: 12px;
    line-height: 1;
}

.step h3 {
    margin-bottom: 10px;
    font-size: 1.1rem;
}

.step p {
    color: var(--gray);
    font-size: 0.95rem;
}

/* 案例 */
.cases {
    padding: 80px 0;
}

.case-card {
    background: var(--white);
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    padding: 28px;
    transition: all 0.3s;
}

.case-card:hover {
    box-shadow: 0 10px 40px rgba(0,0,0,0.08);
    transform: translateY(-4px);
}

.case-tag {
    display: inline-block;
    background: var(--gradient);
    color: var(--white);
    padding: 4px 12px;
    border-radius: 6px;
    font-size: 0.75rem;
    font-weight: 600;
    margin-bottom: 12px;
}

.case-card h3 {
    margin-bottom: 10px;
    font-size: 1.1rem;
}

.case-card p {
    color: var(--gray);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* 平台 */
.platforms {
    padding: 60px 0;
    background: var(--dark);
    color: var(--white);
    text-align: center;
}

.platform-tags {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px;
}

.tag {
    background: rgba(255,255,255,0.1);
    border: 1px solid rgba(255,255,255,0.2);
    padding: 8px 20px;
    border-radius: 20px;
    font-size: 0.95rem;
    transition: all 0.2s;
}

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

/* 联系 */
.contact {
    padding: 100px 0;
    text-align: center;
    background: linear-gradient(135deg, #1e1b4b 0%, #0f172a 100%);
    color: var(--white);
}

.contact p {
    color: #94a3b8;
    margin-bottom: 28px;
    font-size: 1.1rem;
}

/* Footer */
footer {
    background: #020617;
    color: #475569;
    text-align: center;
    padding: 24px 0;
    font-size: 0.9rem;
}

/* 响应式 */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.2rem;
    }
    .comparison {
        grid-template-columns: 1fr;
    }
    .compare-arrow {
        transform: rotate(90deg);
        text-align: center;
    }
    .nav-links {
        gap: 14px;
        font-size: 0.85rem;
    }
    .grid {
        grid-template-columns: 1fr;
    }
}