:root {
    --primary: #1a5cff;
    --primary-dark: #1240b8;
    --primary-light: #4d8bff;
    --accent: #00d9ff;
    --text: #1f2937;
    --text-light: #6b7280;
    --bg: #ffffff;
    --bg-alt: #f4f7ff;
    --dark: #0b1020;
    --radius: 16px;
    --shadow: 0 10px 40px rgba(18, 64, 184, 0.10);
    --font: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 76px;
}

section[id] {
    scroll-margin-top: 76px;
}

body {
    font-family: var(--font);
    color: var(--text);
    background: var(--bg);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

img {
    max-width: 100%;
    display: block;
}

a {
    text-decoration: none;
    color: inherit;
}

.container {
    width: min(1160px, 92%);
    margin: 0 auto;
}

/* ========== 头部导航 ========== */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 100;
    background: rgba(11, 16, 32, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    transition: background 0.3s;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 68px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
}

.brand-logo {
    width: 44px;
    height: 44px;
    object-fit: contain;
    border-radius: 8px;
}

.brand-name {
    color: #fff;
    font-size: 18px;
    font-weight: 700;
    letter-spacing: 1px;
    white-space: nowrap;
}

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

.nav a {
    color: rgba(255, 255, 255, 0.85);
    font-size: 15px;
    transition: color 0.25s;
    position: relative;
}

.nav a::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -6px;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: width 0.3s;
}

.nav a:hover {
    color: #fff;
}

.nav a:hover::after {
    width: 100%;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 6px;
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: #fff;
    transition: transform 0.3s, opacity 0.3s;
}

/* ========== 首屏横幅 ========== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    color: #fff;
    overflow: hidden;
    background: linear-gradient(135deg, #0b1020 0%, #14204d 45%, #0b2b6b 100%);
}

.hero-bg {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(circle at 20% 30%, rgba(26, 92, 255, 0.35), transparent 45%),
        radial-gradient(circle at 80% 70%, rgba(0, 217, 255, 0.25), transparent 40%),
        radial-gradient(circle at 70% 20%, rgba(77, 139, 255, 0.2), transparent 50%);
    animation: floatBg 12s ease-in-out infinite alternate;
}

@keyframes floatBg {
    from {
        transform: scale(1) translateY(0);
    }
    to {
        transform: scale(1.06) translateY(-14px);
    }
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    padding: 120px 0 80px;
}

.hero-eyebrow {
    font-size: 14px;
    letter-spacing: 4px;
    color: rgba(255, 255, 255, 0.6);
    margin-bottom: 20px;
}

.hero h1 {
    font-size: clamp(34px, 6vw, 64px);
    font-weight: 800;
    letter-spacing: 6px;
    margin-bottom: 20px;
    background: linear-gradient(90deg, #fff 30%, var(--accent) 70%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero .highlight {
    color: var(--accent);
}

.hero-sub {
    font-size: clamp(15px, 2vw, 19px);
    color: rgba(255, 255, 255, 0.85);
    max-width: 640px;
    margin: 0 auto 36px;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    display: inline-block;
    padding: 9px 24px;
    border-radius: 999px;
    font-size: 13px;
    font-weight: 600;
    transition: transform 0.25s, box-shadow 0.25s;
    cursor: pointer;
    border: 2px solid transparent;
}

.btn-primary {
    background-color: #1a5cff;
    background-image: none;
    color: #fff;
    box-shadow: 0 8px 24px rgba(26, 92, 255, 0.35);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 30px rgba(26, 92, 255, 0.45);
}

.btn-outline {
    border-color: rgba(255, 255, 255, 0.6);
    color: #fff;
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-3px);
}

/* ========== 通用区块 ========== */
.section {
    padding: 112px 0;
}

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

.section-head {
    text-align: center;
    margin-bottom: 56px;
}

.section-tag {
    display: inline-block;
    color: var(--primary);
    font-size: 15px;
    font-weight: 700;
    letter-spacing: 3px;
    background: rgba(26, 92, 255, 0.08);
    padding: 8px 22px;
    border-radius: 999px;
    margin-bottom: 18px;
}

.section-head h2 {
    font-size: clamp(32px, 4.6vw, 50px);
    font-weight: 800;
    letter-spacing: 2px;
    margin-bottom: 16px;
}

.section-desc {
    color: var(--text-light);
    max-width: 720px;
    margin: 0 auto;
    font-size: 17px;
}

/* ========== 关于我们 ========== */
.about-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.about-card {
    background: #fff;
    border: 1px solid rgba(26, 92, 255, 0.08);
    border-radius: var(--radius);
    padding: 32px 28px;
    box-shadow: var(--shadow);
    transition: transform 0.3s, box-shadow 0.3s;
}

.about-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 16px 44px rgba(18, 64, 184, 0.16);
}

.about-card h3 {
    color: var(--primary);
    font-size: 19px;
    margin-bottom: 12px;
    letter-spacing: 1px;
}

.about-card p {
    color: var(--text-light);
    font-size: 15px;
}

/* ========== 服务 ========== */
.service-block {
    margin-bottom: 60px;
}

.service-block:last-child {
    margin-bottom: 0;
}

.service-block-title {
    text-align: center;
    margin-bottom: 32px;
}

.service-block-title h3 {
    font-size: 24px;
    font-weight: 800;
    letter-spacing: 2px;
    display: inline-block;
    position: relative;
    margin-bottom: 6px;
}

.service-block-title p {
    color: var(--text-light);
    font-size: 15px;
}

.service-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.service-grid:has(.service-card:nth-child(2):last-child) {
    grid-template-columns: repeat(2, 1fr);
    max-width: 800px;
    margin: 0 auto;
}

.service-card {
    background: #fff;
    border: 1px solid rgba(26, 92, 255, 0.08);
    border-radius: var(--radius);
    padding: 32px 28px;
    box-shadow: var(--shadow);
    transition: transform 0.3s, box-shadow 0.3s;
}

.service-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 16px 44px rgba(18, 64, 184, 0.16);
}

.service-icon {
    width: 56px;
    height: 56px;
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    margin-bottom: 18px;
    box-shadow: 0 8px 20px rgba(26, 92, 255, 0.3);
}

.service-icon svg {
    width: 28px;
    height: 28px;
}

.service-card h4 {
    font-size: 18px;
    margin-bottom: 10px;
    letter-spacing: 1px;
}

.service-card p {
    color: var(--text-light);
    font-size: 14.5px;
}

/* ========== 优势 ========== */
.advantage-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.advantage-item {
    text-align: center;
    padding: 36px 24px;
    border-radius: var(--radius);
    background: linear-gradient(160deg, #fff, #f0f5ff);
    border: 1px solid rgba(26, 92, 255, 0.1);
    transition: transform 0.3s;
}

.advantage-item:hover {
    transform: translateY(-6px);
}

.adv-num {
    display: block;
    font-size: 40px;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 12px;
}

.advantage-item h4 {
    font-size: 17px;
    margin-bottom: 8px;
    letter-spacing: 1px;
}

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

/* ========== 联系我们 ========== */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 32px;
    max-width: 900px;
    margin: 0 auto;
}

.contact-info,
.contact-cta {
    background: #fff;
    border-radius: var(--radius);
    padding: 40px 36px;
    box-shadow: var(--shadow);
    border: 1px solid rgba(26, 92, 255, 0.08);
}

.contact-info p {
    margin-bottom: 14px;
    font-size: 15.5px;
}

.contact-info a {
    color: var(--primary);
    font-weight: 600;
}

.contact-cta {
    background: linear-gradient(135deg, #0b1020, #14204d);
    color: #fff;
    text-align: center;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 14px;
}

.contact-cta p:first-child {
    font-size: 22px;
    font-weight: 700;
}

.contact-cta .btn {
    align-self: center;
    margin-top: 6px;
}

/* ========== 页脚 ========== */
.site-footer {
    background: var(--dark);
    color: rgba(255, 255, 255, 0.7);
    text-align: center;
    padding: 32px 0;
    font-size: 14px;
}

.footer-motto {
    margin-top: 8px;
    color: var(--accent);
    font-weight: 600;
    letter-spacing: 3px;
}

/* ========== 滚动显现动画 ========== */
.reveal {
    opacity: 0;
    transform: translateY(28px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ========== 响应式 ========== */
@media (max-width: 992px) {
    .about-grid,
    .service-grid,
    .advantage-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .section {
        padding: 64px 0;
    }

    .nav {
        position: fixed;
        top: 68px;
        right: -100%;
        flex-direction: column;
        background: var(--dark);
        width: min(280px, 80%);
        height: 100vh;
        padding: 40px 32px;
        gap: 28px;
        transition: right 0.35s ease;
        border-left: 1px solid rgba(255, 255, 255, 0.08);
    }

    .nav.open {
        right: 0;
    }

    .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);
    }

    .brand-name {
        font-size: 15px;
    }

    .hero-content {
        padding: 110px 0 60px;
    }
}

@media (max-width: 560px) {
    .about-grid,
    .service-grid,
    .advantage-grid,
    .contact-grid {
        grid-template-columns: 1fr;
    }

    .service-grid:has(.service-card:nth-child(2):last-child) {
        grid-template-columns: 1fr;
    }
}