/* ========== 基础变量 ========== */
:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #3b82f6;
    --accent: #06b6d4;
    --bg: #ffffff;
    --bg-dark: #0f172a;
    --bg-dark-card: #1e293b;
    --text: #1e293b;
    --text-light: #64748b;
    --text-dark-mode: #e2e8f0;
    --border: #e2e8f0;
    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 1px 3px rgba(0,0,0,.06), 0 4px 12px rgba(0,0,0,.06);
    --shadow-lg: 0 4px 24px rgba(0,0,0,.1);
    --transition: .3s cubic-bezier(.4,0,.2,1);
    --font: 'SF Pro Display', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
}

/* ========== Reset ========== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }
body {
    font-family: var(--font);
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img { max-width: 100%; display: block; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }
input, textarea, select {
    font-family: inherit;
    font-size: 1rem;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    padding: .75rem 1rem;
    transition: var(--transition);
    width: 100%;
    background: var(--bg);
    color: var(--text);
}
input:focus, textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37,99,235,.15);
}

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

/* ========== 按钮 ========== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: .625rem 1.5rem;
    border-radius: var(--radius-sm);
    font-weight: 600;
    font-size: .9375rem;
    transition: var(--transition);
    white-space: nowrap;
}
.btn-primary {
    background: var(--primary);
    color: #fff;
}
.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: 0 4px 16px rgba(37,99,235,.35);
}
.btn-outline {
    border: 1.5px solid var(--primary);
    color: var(--primary);
    background: transparent;
}
.btn-outline:hover {
    background: var(--primary);
    color: #fff;
    transform: translateY(-1px);
}
.btn-lg {
    padding: .875rem 2rem;
    font-size: 1.0625rem;
}
.btn-block { width: 100%; }

/* ========== 导航栏 ========== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(255,255,255,.85);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid transparent;
    transition: var(--transition);
}
.navbar.scrolled {
    border-bottom-color: var(--border);
    box-shadow: var(--shadow);
}
.nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}
.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 1.5rem;
    font-weight: 800;
}
.logo-icon {
    color: var(--primary);
    font-size: 1.75rem;
}
.logo-text { color: var(--text); }
.logo-highlight { color: var(--primary); }
.nav-links {
    display: flex;
    gap: 8px;
}
.nav-links a {
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    font-size: .9375rem;
    font-weight: 500;
    color: var(--text-light);
    transition: var(--transition);
}
.nav-links a:hover,
.nav-links a.active {
    color: var(--primary);
    background: rgba(37,99,235,.06);
}
.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 8px;
}
.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text);
    border-radius: 2px;
    transition: var(--transition);
}

/* ========== Hero ========== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 120px 0 80px;
    overflow: hidden;
    background: linear-gradient(135deg, #f0f5ff 0%, #e0f2fe 50%, #f0fdf4 100%);
}
.hero-bg-animation {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(circle at 20% 50%, rgba(37,99,235,.08) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(6,182,212,.08) 0%, transparent 50%),
        radial-gradient(circle at 60% 80%, rgba(139,92,246,.06) 0%, transparent 50%);
    animation: heroBgPulse 8s ease-in-out infinite alternate;
}
@keyframes heroBgPulse {
    0% { opacity: .7; transform: scale(1); }
    100% { opacity: 1; transform: scale(1.05); }
}
.hero-content {
    position: relative;
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}
.hero-badge {
    display: inline-block;
    padding: 6px 20px;
    border-radius: 100px;
    background: rgba(37,99,235,.1);
    color: var(--primary);
    font-size: .875rem;
    font-weight: 600;
    margin-bottom: 24px;
}
.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.15;
    margin-bottom: 24px;
    letter-spacing: -.02em;
}
.gradient-text {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.hero-desc {
    font-size: 1.175rem;
    color: var(--text-light);
    max-width: 640px;
    margin: 0 auto 40px;
    line-height: 1.7;
}
.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-bottom: 64px;
}
.hero-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 32px;
    padding: 32px;
    background: rgba(255,255,255,.7);
    backdrop-filter: blur(8px);
    border-radius: var(--radius);
    border: 1px solid rgba(255,255,255,.8);
    box-shadow: var(--shadow);
}
.stat-item { text-align: center; }
.stat-number {
    font-size: 2.25rem;
    font-weight: 800;
    color: var(--primary);
    line-height: 1.2;
}
.stat-suffix {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}
.stat-label {
    display: block;
    font-size: .875rem;
    color: var(--text-light);
    margin-top: 4px;
}

/* ========== 通用 Section ========== */
.section { padding: 100px 0; }
.section-dark {
    background: var(--bg-dark);
    color: var(--text-dark-mode);
}
.section-dark + .section-dark {
    border-top: 1px solid rgba(255,255,255,.06);
}
.section-header {
    text-align: center;
    margin-bottom: 64px;
}
.section-badge {
    display: inline-block;
    padding: 4px 16px;
    border-radius: 100px;
    font-size: .8125rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: .08em;
    margin-bottom: 16px;
    background: rgba(37,99,235,.1);
    color: var(--primary);
}
.section-dark .section-badge {
    background: rgba(37,99,235,.2);
    color: var(--primary-light);
}
.section-title {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 16px;
    letter-spacing: -.01em;
}
.section-desc {
    font-size: 1.125rem;
    color: var(--text-light);
    max-width: 560px;
    margin: 0 auto;
}
.section-dark .section-desc {
    color: #94a3b8;
}

/* ========== 服务卡片 ========== */
.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}
.service-card {
    background: var(--bg-dark-card);
    border: 1px solid rgba(255,255,255,.06);
    border-radius: var(--radius);
    padding: 32px;
    transition: var(--transition);
}
.service-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 32px rgba(37,99,235,.12);
    border-color: rgba(37,99,235,.3);
}
.service-icon {
    font-size: 2.5rem;
    margin-bottom: 16px;
}
.service-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 8px;
}
.service-card p {
    color: #94a3b8;
    font-size: .9375rem;
    margin-bottom: 16px;
}
.service-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}
.service-tags li {
    padding: 4px 12px;
    border-radius: 100px;
    font-size: .8125rem;
    background: rgba(255,255,255,.06);
    color: #94a3b8;
}

/* ========== 核心优势 ========== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}
.feature-item {
    padding: 32px;
    background: var(--bg-dark-card);
    border-radius: var(--radius);
    border: 1px solid rgba(255,255,255,.06);
    transition: var(--transition);
}
.feature-item:hover {
    transform: translateY(-4px);
    border-color: rgba(37,99,235,.3);
    box-shadow: 0 8px 32px rgba(37,99,235,.12);
}
.feature-number {
    font-size: 3rem;
    font-weight: 900;
    color: rgba(37,99,235,.2);
    line-height: 1;
    margin-bottom: 16px;
}
.feature-item h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 12px;
}
.feature-item p {
    color: #94a3b8;
    font-size: .9375rem;
    line-height: 1.7;
}

/* ========== 数据展示 ========== */
.data-tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 24px;
    justify-content: center;
}
.tab-btn {
    padding: 10px 24px;
    border-radius: var(--radius-sm);
    font-size: .9375rem;
    font-weight: 600;
    color: #94a3b8;
    background: var(--bg-dark-card);
    transition: var(--transition);
}
.tab-btn.active,
.tab-btn:hover {
    background: var(--primary);
    color: #fff;
}
.data-table-wrapper {
    overflow-x: auto;
    border-radius: var(--radius);
    border: 1px solid rgba(255,255,255,.06);
    box-shadow: none;
}
.data-table {
    width: 100%;
    border-collapse: collapse;
    font-size: .9rem;
}
.data-table th {
    background: var(--bg-dark-card);
    padding: 14px 16px;
    text-align: left;
    font-weight: 600;
    color: var(--text-dark-mode);
    border-bottom: 2px solid rgba(255,255,255,.08);
    white-space: nowrap;
}
.data-table td {
    padding: 12px 16px;
    border-bottom: 1px solid rgba(255,255,255,.06);
    white-space: nowrap;
    color: #cbd5e1;
}
.data-table tbody tr:hover {
    background: rgba(255,255,255,.03);
}
.data-table tbody tr:last-child td {
    border-bottom: none;
}
.data-note {
    text-align: center;
    margin-top: 24px;
    color: #94a3b8;
    font-size: .9375rem;
}
.data-note a {
    color: var(--primary);
    font-weight: 600;
}

/* ========== 工作流程 ========== */
.workflow-steps {
    display: flex;
    align-items: flex-start;
    justify-content: center;
    gap: 0;
}
.workflow-step {
    text-align: center;
    flex: 0 0 200px;
}
.step-circle {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 800;
    margin: 0 auto 16px;
    box-shadow: 0 4px 16px rgba(37,99,235,.35);
}
.workflow-step h3 {
    font-size: 1.125rem;
    font-weight: 700;
    margin-bottom: 8px;
}
.workflow-step p {
    font-size: .875rem;
    color: #94a3b8;
    line-height: 1.6;
}
.workflow-connector {
    flex: 1;
    max-width: 80px;
    height: 2px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    margin-top: 32px;
    border-radius: 2px;
    opacity: .4;
}

/* ========== 价格方案 ========== */
.pricing-hero {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 64px;
    align-items: center;
    max-width: 960px;
    margin: 0 auto;
}
.pricing-hero-left {
    text-align: center;
}
.pricing-price-big {
    margin-bottom: 8px;
}
.price-approx {
    font-size: 1rem;
    color: #94a3b8;
    letter-spacing: .05em;
}
.price-main-row {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 4px;
    margin-top: 4px;
}
.price-currency {
    font-size: 2rem;
    font-weight: 800;
    color: #60a5fa;
}
.price-amount {
    font-size: 5.5rem;
    font-weight: 900;
    line-height: 1;
    background: linear-gradient(135deg, #60a5fa, #38bdf8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.price-period {
    font-size: 1.25rem;
    color: #94a3b8;
    font-weight: 500;
}
.pricing-slogan {
    font-size: 1.0625rem;
    color: #94a3b8;
    margin-bottom: 32px;
}
.pricing-sub-note {
    margin-top: 16px;
    font-size: .875rem;
    color: #64748b;
}
.pricing-hero-right {
    display: flex;
    flex-direction: column;
    gap: 20px;
}
.pricing-point {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    padding: 20px;
    background: var(--bg-dark-card);
    border-radius: var(--radius-sm);
    border: 1px solid rgba(255,255,255,.06);
    transition: var(--transition);
}
.pricing-point:hover {
    border-color: rgba(37,99,235,.25);
    background: rgba(37,99,235,.06);
}
.pricing-point-icon {
    font-size: 1.75rem;
    flex-shrink: 0;
    line-height: 1.3;
}
.pricing-point h4 {
    font-size: .9375rem;
    font-weight: 700;
    margin-bottom: 4px;
}
.pricing-point p {
    font-size: .875rem;
    color: #94a3b8;
    line-height: 1.5;
}

/* ========== 联系我们 ========== */
.contact-cards {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    max-width: 800px;
    margin: 0 auto;
}
.contact-item {
    text-align: center;
    padding: 32px 24px;
    background: var(--bg-dark-card);
    border-radius: var(--radius);
    border: 1px solid rgba(255,255,255,.06);
    transition: var(--transition);
}
.contact-item:hover {
    transform: translateY(-4px);
    border-color: rgba(37,99,235,.3);
    box-shadow: 0 8px 32px rgba(37,99,235,.12);
}
.contact-icon {
    font-size: 2.5rem;
    margin-bottom: 16px;
}
.contact-item h4 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 8px;
}
.contact-item p {
    color: #94a3b8;
    font-size: .9375rem;
    word-break: break-all;
}

/* ========== 页脚 ========== */
.footer {
    background: #020617;
    color: #94a3b8;
    padding: 64px 0 0;
}
.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 48px;
    padding-bottom: 48px;
    border-bottom: 1px solid rgba(255,255,255,.06);
}
.footer-brand p {
    margin-top: 16px;
    font-size: .9375rem;
    line-height: 1.7;
}
.footer-brand .logo-text { color: #e2e8f0; }
.footer-links h4 {
    color: #e2e8f0;
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 16px;
}
.footer-links li { margin-bottom: 10px; }
.footer-links a {
    font-size: .9375rem;
    transition: var(--transition);
}
.footer-links a:hover { color: var(--primary-light); }
.footer-bottom {
    text-align: center;
    padding: 24px 0;
    font-size: .8125rem;
    color: #475569;
}

/* ========== 回到顶部 ========== */
.back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    font-size: 1.25rem;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 16px rgba(37,99,235,.35);
    opacity: 0;
    visibility: hidden;
    transform: translateY(16px);
    transition: var(--transition);
    z-index: 999;
}
.back-to-top.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}
.back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
}

/* ========== Toast ========== */
.toast {
    position: fixed;
    bottom: 32px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--bg-dark);
    color: #fff;
    padding: 14px 28px;
    border-radius: var(--radius-sm);
    font-size: .9375rem;
    font-weight: 500;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    transition: var(--transition);
    z-index: 10000;
    white-space: nowrap;
}
.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

/* ========== 动画 ========== */
.fade-in {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity .6s ease, transform .6s ease;
}
.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ========== 响应式 ========== */
@media (max-width: 1024px) {
    .hero-title { font-size: 2.75rem; }
    .section-title { font-size: 2rem; }
    .services-grid,
    .features-grid { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
}

@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(255,255,255,.98);
        backdrop-filter: blur(16px);
        flex-direction: column;
        padding: 16px 24px;
        border-bottom: 1px solid var(--border);
        transform: translateY(-120%);
        transition: var(--transition);
        opacity: 0;
    }
    .nav-links.open {
        transform: translateY(0);
        opacity: 1;
    }
    .nav-toggle { display: flex; }
    .nav-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
    .nav-toggle.active span:nth-child(2) { opacity: 0; }
    .nav-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

    .hero { padding: 100px 0 60px; }
    .hero-title { font-size: 2.25rem; }
    .hero-desc { font-size: 1rem; }
    .hero-actions { flex-direction: column; align-items: center; }
    .hero-stats {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
        padding: 24px;
    }
    .stat-number { font-size: 1.75rem; }
    .section { padding: 64px 0; }
    .section-title { font-size: 1.75rem; }
    .services-grid,
    .features-grid { grid-template-columns: 1fr; }
    .pricing-hero { grid-template-columns: 1fr; gap: 40px; }
    .pricing-hero-left { margin-bottom: 8px; }
    .price-amount { font-size: 4rem; }
    .workflow-steps { flex-direction: column; align-items: center; }
    .workflow-connector {
        width: 2px;
        height: 32px;
        max-width: none;
        margin: 0;
    }
    .contact-cards { grid-template-columns: 1fr; max-width: 400px; }
    .footer-grid { grid-template-columns: 1fr; gap: 32px; }
}

@media (max-width: 480px) {
    .hero-title { font-size: 1.75rem; }
    .container { padding: 0 16px; }
}