/* ===================================================
   内蒙古书智科技有限公司 - 官方门户网站样式
   科技风深色主题，响应式适配 PC/平板/手机
   =================================================== */

/* CSS 变量 */
:root {
    /* 主色调 */
    --color-bg: #050810;
    --color-bg-alt: #0a0f1c;
    --color-bg-card: rgba(16, 23, 41, 0.6);
    --color-bg-card-hover: rgba(20, 30, 56, 0.8);
    --color-border: rgba(56, 189, 248, 0.15);
    --color-border-hover: rgba(56, 189, 248, 0.4);

    /* 文字 */
    --color-text: #e6edf7;
    --color-text-secondary: #9aa8c4;
    --color-text-muted: #64748b;

    /* 强调色 */
    --color-primary: #00d4ff;
    --color-primary-dark: #0099cc;
    --color-secondary: #7c3aed;
    --color-accent: #06b6d4;

    /* 渐变 */
    --gradient-primary: linear-gradient(135deg, #00d4ff 0%, #7c3aed 100%);
    --gradient-text: linear-gradient(135deg, #00d4ff 0%, #7c3aed 100%);
    --gradient-glow: radial-gradient(circle, rgba(0, 212, 255, 0.15) 0%, transparent 70%);

    /* 阴影 */
    --shadow-glow: 0 0 30px rgba(0, 212, 255, 0.15);
    --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.3);

    /* 间距 */
    --container-width: 1200px;
    --container-padding: 24px;
    --section-padding: 100px 0;

    /* 过渡 */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);

    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
}

/* 重置样式 */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica,
        Arial, sans-serif;
    background-color: var(--color-bg);
    color: var(--color-text);
    line-height: 1.7;
    font-size: 16px;
    overflow-x: hidden;
    /* 网格纹理背景 */
    background-image:
        linear-gradient(rgba(56, 189, 248, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(56, 189, 248, 0.03) 1px, transparent 1px);
    background-size: 50px 50px;
}

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

ul {
    list-style: none;
}

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

button {
    cursor: pointer;
    border: none;
    background: none;
    font-family: inherit;
}

/* 容器 */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

/* ===================================================
   顶部导航栏
   =================================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(5, 8, 16, 0.5);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid transparent;
    transition: var(--transition);
}

.header.scrolled {
    background: rgba(5, 8, 16, 0.85);
    border-bottom-color: var(--color-border);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    font-size: 18px;
}

.logo-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background: var(--gradient-primary);
    color: #fff;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 800;
    letter-spacing: -0.5px;
    box-shadow: var(--shadow-glow);
}

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

.nav-menu {
    display: flex;
    gap: 8px;
}

.nav-link {
    padding: 8px 16px;
    color: var(--color-text-secondary);
    font-size: 15px;
    font-weight: 500;
    border-radius: var(--radius-sm);
    position: relative;
    transition: var(--transition);
}

.nav-link:hover {
    color: var(--color-text);
    background: rgba(56, 189, 248, 0.08);
}

.nav-link.active {
    color: var(--color-primary);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 20px;
    height: 2px;
    background: var(--color-primary);
    border-radius: 2px;
}

/* 汉堡菜单按钮 */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 28px;
    height: 20px;
    padding: 0;
}

.menu-toggle span {
    display: block;
    width: 100%;
    height: 2px;
    background: var(--color-text);
    border-radius: 2px;
    transition: var(--transition);
}

.menu-toggle.active span:nth-child(1) {
    transform: translateY(9px) rotate(45deg);
}

.menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
    transform: translateY(-9px) rotate(-45deg);
}

/* ===================================================
   Hero 首屏
   =================================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    overflow: hidden;
    padding: 100px 0 60px;
}

.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
    overflow: hidden;
}

/* 网格层 */
.grid-overlay {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(56, 189, 248, 0.08) 1px, transparent 1px),
        linear-gradient(90deg, rgba(56, 189, 248, 0.08) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse at center, black 30%, transparent 75%);
    -webkit-mask-image: radial-gradient(ellipse at center, black 30%, transparent 75%);
}

/* 光球 */
.glow-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.5;
    animation: float 8s ease-in-out infinite;
}

.glow-orb-1 {
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, #00d4ff 0%, transparent 70%);
    top: -100px;
    left: -100px;
}

.glow-orb-2 {
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, #7c3aed 0%, transparent 70%);
    bottom: -200px;
    right: -150px;
    animation-delay: 2s;
}

.glow-orb-3 {
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, #06b6d4 0%, transparent 70%);
    top: 40%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation-delay: 4s;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(30px, -30px) scale(1.05); }
    66% { transform: translate(-20px, 20px) scale(0.95); }
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 900px;
}

.hero-tagline {
    display: inline-block;
    padding: 6px 16px;
    margin-bottom: 24px;
    background: rgba(0, 212, 255, 0.1);
    border: 1px solid rgba(0, 212, 255, 0.3);
    border-radius: 100px;
    color: var(--color-primary);
    font-size: 14px;
    letter-spacing: 1px;
}

.hero-title {
    font-size: clamp(36px, 6vw, 64px);
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 24px;
    letter-spacing: -1px;
}

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

.hero-desc {
    font-size: clamp(15px, 2vw, 18px);
    color: var(--color-text-secondary);
    margin-bottom: 40px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

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

/* 按钮 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 32px;
    font-size: 15px;
    font-weight: 600;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    cursor: pointer;
    border: 1px solid transparent;
}

.btn-primary {
    background: var(--gradient-primary);
    color: #fff;
    box-shadow: 0 4px 20px rgba(0, 212, 255, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 30px rgba(0, 212, 255, 0.5);
}

.btn-outline {
    background: transparent;
    color: var(--color-text);
    border-color: var(--color-border-hover);
}

.btn-outline:hover {
    background: rgba(0, 212, 255, 0.08);
    border-color: var(--color-primary);
}

.btn-block {
    width: 100%;
}

/* 滚动指示器 */
.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 1;
    width: 24px;
    height: 40px;
    border: 2px solid var(--color-text-secondary);
    border-radius: 14px;
    display: flex;
    justify-content: center;
    padding-top: 6px;
}

.mouse {
    width: 4px;
    height: 8px;
    background: var(--color-primary);
    border-radius: 2px;
    animation: scrollWheel 1.6s ease-in-out infinite;
}

@keyframes scrollWheel {
    0% { opacity: 0; transform: translateY(-4px); }
    50% { opacity: 1; }
    100% { opacity: 0; transform: translateY(12px); }
}

/* ===================================================
   通用区块
   =================================================== */
.section {
    padding: var(--section-padding);
    position: relative;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-label {
    display: inline-block;
    padding: 4px 14px;
    background: rgba(0, 212, 255, 0.08);
    border: 1px solid rgba(0, 212, 255, 0.2);
    border-radius: 100px;
    color: var(--color-primary);
    font-size: 12px;
    letter-spacing: 2px;
    font-weight: 600;
    margin-bottom: 16px;
}

.section-title {
    font-size: clamp(28px, 4vw, 42px);
    font-weight: 700;
    margin-bottom: 16px;
    letter-spacing: -0.5px;
}

.section-divider {
    width: 60px;
    height: 3px;
    background: var(--gradient-primary);
    border-radius: 3px;
    margin: 0 auto 20px;
}

.section-subtitle {
    color: var(--color-text-secondary);
    font-size: 16px;
    max-width: 600px;
    margin: 0 auto;
}

/* ===================================================
   关于我们
   =================================================== */
.about {
    background: var(--color-bg-alt);
}

.about-grid {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 60px;
    align-items: center;
}

.about-text p {
    color: var(--color-text-secondary);
    margin-bottom: 20px;
    font-size: 16px;
    line-height: 1.9;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.stat-card {
    padding: 28px 20px;
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    text-align: center;
    transition: var(--transition);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.stat-card:hover {
    border-color: var(--color-border-hover);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.stat-number {
    font-size: 42px;
    font-weight: 800;
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
    line-height: 1;
    margin-bottom: 8px;
}

.stat-number sup {
    font-size: 20px;
    vertical-align: super;
}

.stat-label {
    color: var(--color-text-secondary);
    font-size: 14px;
}

/* ===================================================
   业务范围
   =================================================== */
.business-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.business-card {
    padding: 32px 24px;
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    transition: var(--transition);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    position: relative;
    overflow: hidden;
}

.business-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-primary);
    transform: scaleX(0);
    transform-origin: left;
    transition: var(--transition);
}

.business-card:hover {
    border-color: var(--color-border-hover);
    background: var(--color-bg-card-hover);
    transform: translateY(-6px);
    box-shadow: var(--shadow-glow);
}

.business-card:hover::before {
    transform: scaleX(1);
}

.card-icon {
    width: 56px;
    height: 56px;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0, 212, 255, 0.1);
    border-radius: var(--radius-md);
    color: var(--color-primary);
}

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

.card-title {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--color-text);
}

.card-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.card-list li {
    color: var(--color-text-secondary);
    font-size: 14px;
    padding-left: 16px;
    position: relative;
    line-height: 1.6;
}

.card-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 10px;
    width: 6px;
    height: 6px;
    background: var(--color-primary);
    border-radius: 50%;
    opacity: 0.7;
}

/* ===================================================
   服务能力
   =================================================== */
.services {
    background: var(--color-bg-alt);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.service-item {
    padding: 40px 30px;
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    text-align: center;
    transition: var(--transition);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.service-item:hover {
    border-color: var(--color-border-hover);
    transform: translateY(-6px);
    box-shadow: var(--shadow-glow);
}

.service-icon {
    width: 72px;
    height: 72px;
    margin: 0 auto 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient-primary);
    border-radius: 50%;
    color: #fff;
    box-shadow: 0 4px 20px rgba(0, 212, 255, 0.3);
}

.service-icon svg {
    width: 32px;
    height: 32px;
}

.service-title {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 14px;
}

.service-desc {
    color: var(--color-text-secondary);
    font-size: 15px;
    line-height: 1.8;
}

/* ===================================================
   解决方案
   =================================================== */
.solutions-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.solution-card {
    padding: 30px 24px;
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    transition: var(--transition);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.solution-card:hover {
    border-color: var(--color-border-hover);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.solution-icon {
    width: 48px;
    height: 48px;
    margin-bottom: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-sm);
    color: #fff;
}

.solution-icon svg {
    width: 24px;
    height: 24px;
}

.gradient-1 { background: linear-gradient(135deg, #00d4ff, #0099cc); }
.gradient-2 { background: linear-gradient(135deg, #7c3aed, #5b21b6); }
.gradient-3 { background: linear-gradient(135deg, #06b6d4, #0891b2); }
.gradient-4 { background: linear-gradient(135deg, #f43f5e, #be123c); }
.gradient-5 { background: linear-gradient(135deg, #10b981, #047857); }
.gradient-6 { background: linear-gradient(135deg, #f59e0b, #b45309); }

.solution-card h4 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 8px;
}

.solution-card p {
    color: var(--color-text-secondary);
    font-size: 14px;
    line-height: 1.6;
}

/* ===================================================
   联系我们
   =================================================== */
.contact {
    background: var(--color-bg-alt);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
}

.contact-title {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 24px;
}

.contact-list {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.contact-list li {
    display: flex;
    gap: 16px;
    align-items: flex-start;
}

.contact-icon {
    flex-shrink: 0;
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0, 212, 255, 0.1);
    border-radius: var(--radius-sm);
    color: var(--color-primary);
}

.contact-icon svg {
    width: 22px;
    height: 22px;
}

.contact-label {
    color: var(--color-text-muted);
    font-size: 13px;
    margin-bottom: 4px;
}

.contact-value {
    color: var(--color-text);
    font-size: 15px;
    font-weight: 500;
}

/* 联系表单 */
.contact-form-wrap {
    padding: 32px;
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-size: 14px;
    color: var(--color-text-secondary);
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    background: rgba(5, 8, 16, 0.6);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    color: var(--color-text);
    font-size: 15px;
    font-family: inherit;
    transition: var(--transition);
    resize: vertical;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(0, 212, 255, 0.1);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--color-text-muted);
}

.form-tip {
    margin-top: 16px;
    padding: 12px 16px;
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.3);
    border-radius: var(--radius-sm);
    color: #10b981;
    font-size: 14px;
    text-align: center;
}

/* ===================================================
   页脚
   =================================================== */
.footer {
    background: #02040a;
    border-top: 1px solid var(--color-border);
    padding-top: 60px;
}

.footer-container {
    display: grid;
    grid-template-columns: 1.5fr 2fr;
    gap: 60px;
    padding-bottom: 40px;
}

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

.footer-desc {
    color: var(--color-text-secondary);
    font-size: 14px;
    line-height: 1.7;
    max-width: 360px;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.footer-col h5 {
    color: var(--color-text);
    font-size: 15px;
    font-weight: 700;
    margin-bottom: 16px;
}

.footer-col a {
    display: block;
    color: var(--color-text-secondary);
    font-size: 14px;
    padding: 4px 0;
    transition: var(--transition);
}

.footer-col a:hover {
    color: var(--color-primary);
    padding-left: 4px;
}

.footer-bottom {
    border-top: 1px solid var(--color-border);
    padding: 20px 0;
}

.footer-bottom .container {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
    text-align: center;
}

.footer-bottom p {
    color: var(--color-text-muted);
    font-size: 13px;
}

.footer-bottom a {
    color: var(--color-text-muted);
    transition: var(--transition);
}

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

.footer-sep {
    margin: 0 8px;
    color: var(--color-text-muted);
}

/* ===================================================
   返回顶部
   =================================================== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 48px;
    height: 48px;
    background: var(--gradient-primary);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 20px rgba(0, 212, 255, 0.4);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: var(--transition);
    z-index: 999;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    transform: translateY(-4px);
    box-shadow: 0 6px 30px rgba(0, 212, 255, 0.6);
}

.back-to-top svg {
    width: 22px;
    height: 22px;
}

/* ===================================================
   滚动渐入动画
   =================================================== */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: var(--transition-slow);
}

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

/* ===================================================
   响应式：平板 (768px - 1199px)
   =================================================== */
@media (max-width: 1199px) {
    :root {
        --section-padding: 80px 0;
    }

    .about-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .business-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .solutions-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .footer-container {
        grid-template-columns: 1fr;
        gap: 40px;
    }
}

/* ===================================================
   响应式：手机 (<768px)
   =================================================== */
@media (max-width: 767px) {
    :root {
        --container-padding: 16px;
        --section-padding: 60px 0;
    }

    body {
        font-size: 15px;
    }

    /* 导航栏 */
    .nav-container {
        height: 60px;
    }

    .menu-toggle {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        top: 60px;
        left: 0;
        right: 0;
        flex-direction: column;
        background: rgba(5, 8, 16, 0.95);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        padding: 16px;
        gap: 4px;
        border-bottom: 1px solid var(--color-border);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: var(--transition);
    }

    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .nav-link {
        display: block;
        padding: 12px 16px;
        border-radius: var(--radius-sm);
    }

    .nav-link.active::after {
        display: none;
    }

    /* Hero */
    .hero {
        padding: 80px 0 40px;
        min-height: 90vh;
    }

    .hero-actions {
        flex-direction: column;
        width: 100%;
        max-width: 280px;
        margin: 0 auto;
    }

    .btn {
        width: 100%;
    }

    /* 关于 */
    .about-stats {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }

    .stat-card {
        padding: 20px 12px;
    }

    .stat-number {
        font-size: 32px;
    }

    /* 业务范围 */
    .business-grid {
        grid-template-columns: 1fr;
    }

    /* 服务能力 */
    .services-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .service-item {
        padding: 30px 24px;
    }

    /* 解决方案 */
    .solutions-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }

    /* 联系我们 */
    .contact-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .contact-form-wrap {
        padding: 24px 20px;
    }

    /* 页脚 */
    .footer-links {
        grid-template-columns: repeat(3, 1fr);
        gap: 20px;
    }

    .footer-bottom .container {
        flex-direction: column;
        text-align: center;
    }

    /* 返回顶部 */
    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 42px;
        height: 42px;
    }
}

/* ===================================================
   响应式：超小屏 (<480px)
   =================================================== */
@media (max-width: 479px) {
    .solutions-grid {
        grid-template-columns: 1fr;
    }

    .footer-links {
        grid-template-columns: 1fr;
    }

    .hero-title {
        font-size: 32px;
    }
}

/* ===================================================
   减少动画偏好
   =================================================== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }

    .reveal {
        opacity: 1;
        transform: none;
    }
}