/* ====================
   风格三：商务专业风格
   类似腾讯、微软的设计
   ==================== */

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

:root {
    --primary: #1a56db;
    --primary-light: #3b82f6;
    --primary-dark: #1e40af;
    --secondary: #0891b2;
    --text-dark: #111827;
    --text-body: #374151;
    --text-muted: #6b7280;
    --bg-white: #ffffff;
    --bg-light: #f9fafb;
    --bg-gray: #f3f4f6;
    --border: #e5e7eb;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

html {
    scroll-behavior: smooth;
}

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

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

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: var(--bg-white);
    border-bottom: 1px solid var(--border);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
}

.logo-icon {
    width: 36px;
    height: 36px;
}

.logo-text {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-dark);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 28px;
    align-items: center;
}

.nav-menu a {
    color: var(--text-body);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s ease;
    position: relative;
}

.nav-menu a:not(.btn):hover {
    color: var(--primary);
}

.nav-menu a:not(.btn)::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: width 0.3s ease;
}

.nav-menu a:not(.btn):hover::after {
    width: 100%;
}

.nav-menu .btn-primary {
    padding: 10px 20px;
    border-radius: 6px;
    box-shadow: 0 2px 8px rgba(26, 86, 219, 0.3);
    font-weight: 600;
}

.nav-menu .btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(26, 86, 219, 0.4);
}

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

.nav-toggle span {
    width: 22px;
    height: 2px;
    background: var(--text-dark);
    transition: 0.3s;
}

/* 按钮 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.2s;
    cursor: pointer;
    border: none;
}

.btn-sm {
    padding: 8px 16px;
    font-size: 0.85rem;
}

.btn-lg {
    padding: 14px 28px;
    font-size: 1rem;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
}

.btn-outline {
    background: transparent;
    color: var(--primary);
    border: 2px solid var(--primary);
}

.btn-outline:hover {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
    box-shadow: 0 4px 12px rgba(26, 86, 219, 0.3);
}

.btn-block {
    width: 100%;
}

/* Hero区域 */
.hero {
    padding: 140px 24px 100px;
    background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 50%, #f0fdf4 100%);
}

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

.hero-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 700;
    line-height: 1.2;
    color: var(--text-dark);
    margin-bottom: 20px;
}

.text-primary {
    color: var(--primary);
}

.hero-desc {
    font-size: 1.1rem;
    color: var(--text-body);
    margin-bottom: 24px;
    line-height: 1.8;
}

.hero-features {
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    margin-bottom: 32px;
}

.hero-feature {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.9rem;
    color: var(--text-body);
}

.feature-icon {
    width: 20px;
    height: 20px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.7rem;
}

.hero-buttons {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

.hero-image {
    position: relative;
    height: 400px;
}

.hero-card {
    position: absolute;
    background: var(--bg-white);
    border-radius: 12px;
    box-shadow: var(--shadow-xl);
}

.card-main {
    width: 320px;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    overflow: hidden;
}

.card-header {
    display: flex;
    gap: 6px;
    padding: 12px 16px;
    background: var(--bg-gray);
}

.card-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: #ef4444;
}

.card-dot:nth-child(2) {
    background: #f59e0b;
}

.card-dot:nth-child(3) {
    background: #22c55e;
}

.card-body {
    padding: 20px;
}

.card-title {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 16px;
}

.card-stats {
    display: flex;
    gap: 24px;
}

.card-stats .stat {
    text-align: center;
}

.card-stats .stat-value {
    display: block;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

.card-stats .stat-label {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.card-float {
    padding: 10px 16px;
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-dark);
    animation: float 4s ease-in-out infinite;
    transition: all 0.3s ease;
}

.card-float:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-lg);
}

.card-float span {
    font-size: 1.1rem;
}

/* 第一行 */
.card-1 {
    top: 5%;
    left: 5%;
    animation-delay: 0s;
    background: linear-gradient(135deg, #fff 0%, #f0f7ff 100%);
    border-left: 3px solid var(--primary);
}

.card-2 {
    top: 5%;
    right: 5%;
    animation-delay: 0.5s;
    background: linear-gradient(135deg, #fff 0%, #f0fff4 100%);
    border-left: 3px solid #10b981;
}

/* 第二行 */
.card-3 {
    top: 28%;
    left: 0;
    animation-delay: 1s;
    background: linear-gradient(135deg, #fff 0%, #fef3f2 100%);
    border-left: 3px solid #ef4444;
}

.card-4 {
    top: 28%;
    right: 0;
    animation-delay: 1.5s;
    background: linear-gradient(135deg, #fff 0%, #fefce8 100%);
    border-left: 3px solid #eab308;
}

/* 第三行 */
.card-5 {
    top: 51%;
    left: 5%;
    animation-delay: 2s;
    background: linear-gradient(135deg, #fff 0%, #fdf4ff 100%);
    border-left: 3px solid #a855f7;
}

.card-6 {
    top: 51%;
    right: 5%;
    animation-delay: 2.5s;
    background: linear-gradient(135deg, #fff 0%, #fff7ed 100%);
    border-left: 3px solid #f97316;
}

/* 底部中心 - 定制开发（突出显示） */
.card-7 {
    top: 74%;
    left: 50%;
    transform: translateX(-50%);
    animation-delay: 0s;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    border-left: none;
    color: white;
    font-weight: 600;
    padding: 12px 24px;
    font-size: 0.95rem;
    box-shadow: 0 4px 15px rgba(26, 86, 219, 0.4);
}

.card-7 span {
    font-size: 1.2rem;
}

.card-7:hover {
    box-shadow: 0 6px 20px rgba(26, 86, 219, 0.5);
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}

.card-7 {
    animation: float7 3s ease-in-out infinite;
}

@keyframes float7 {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(-10px); }
}

/* 通用区块样式 */
.section {
    padding: 80px 24px;
}

.section-header {
    text-align: center;
    margin-bottom: 48px;
}

.section-header.left {
    text-align: left;
}

.section-subtitle {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 1.5px;
    color: var(--primary);
    margin-bottom: 8px;
}

.section-title {
    font-size: clamp(1.75rem, 4vw, 2.25rem);
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 12px;
}

.section-desc {
    color: var(--text-muted);
    font-size: 1rem;
    max-width: 600px;
    margin: 0 auto;
}

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

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
}

.about-text .lead {
    font-size: 1.15rem;
    font-weight: 500;
    color: var(--text-dark);
    margin-bottom: 16px;
}

.about-text p {
    margin-bottom: 16px;
    color: var(--text-body);
}

.about-advantages {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.advantage {
    display: flex;
    gap: 16px;
    padding: 20px;
    background: var(--bg-light);
    border-radius: 10px;
    border: 1px solid var(--border);
    transition: all 0.2s;
}

.advantage:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow);
}

.advantage-icon {
    width: 48px;
    height: 48px;
    background: var(--primary);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.advantage-icon svg {
    width: 24px;
    height: 24px;
    color: white;
}

.advantage-content h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 4px;
}

.advantage-content p {
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* 定制开发 */
.custom-dev {
    background: linear-gradient(135deg, #1a56db 0%, #0891b2 100%);
    color: white;
}

.custom-dev .section-subtitle {
    color: rgba(255, 255, 255, 0.8);
}

.custom-dev .section-title {
    color: white;
}

.custom-dev .section-desc {
    color: rgba(255, 255, 255, 0.9);
}

.custom-intro {
    text-align: center;
    max-width: 800px;
    margin: 0 auto 48px;
}

.custom-intro .lead {
    font-size: 1.1rem;
    line-height: 1.8;
    color: rgba(255, 255, 255, 0.95);
}

.custom-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-bottom: 48px;
}

.custom-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 12px;
    padding: 32px 24px;
    text-align: center;
    transition: all 0.3s ease;
}

.custom-card:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-4px);
}

.custom-icon {
    width: 56px;
    height: 56px;
    margin: 0 auto 16px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.custom-icon svg {
    width: 28px;
    height: 28px;
    stroke: white;
}

.custom-card h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: white;
}

.custom-card p {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.85);
    line-height: 1.6;
}

.custom-process {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 16px;
    padding: 40px;
    margin-bottom: 40px;
}

.custom-process h3 {
    text-align: center;
    font-size: 1.25rem;
    margin-bottom: 32px;
    color: white;
}

.process-steps {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    position: relative;
}

.process-steps::before {
    content: '';
    position: absolute;
    top: 24px;
    left: 10%;
    right: 10%;
    height: 2px;
    background: rgba(255, 255, 255, 0.3);
}

.process-step {
    text-align: center;
    flex: 1;
    position: relative;
    z-index: 1;
}

.step-number {
    width: 48px;
    height: 48px;
    background: white;
    color: var(--primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    font-weight: 700;
    margin: 0 auto 16px;
}

.step-content h4 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 4px;
    color: white;
}

.step-content p {
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.8);
}

.custom-cta {
    text-align: center;
}

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

.custom-cta .btn-primary:hover {
    background: rgba(255, 255, 255, 0.9);
}

@media (max-width: 992px) {
    .custom-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .process-steps {
        flex-wrap: wrap;
        gap: 24px;
    }

    .process-steps::before {
        display: none;
    }

    .process-step {
        flex: 0 0 calc(33.333% - 16px);
    }
}

@media (max-width: 576px) {
    .custom-grid {
        grid-template-columns: 1fr;
    }

    .process-step {
        flex: 0 0 100%;
    }

    .custom-process {
        padding: 24px;
    }
}

/* 解决方案 */
.solutions {
    background: var(--bg-light);
}

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

.solution-card {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 28px;
    transition: all 0.3s;
    position: relative;
}

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

.solution-card.featured {
    border-color: var(--primary);
}

.solution-badge {
    position: absolute;
    top: 16px;
    right: 16px;
    padding: 4px 10px;
    background: var(--primary);
    color: white;
    border-radius: 4px;
    font-size: 0.7rem;
    font-weight: 600;
}

.solution-icon {
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, #dbeafe 0%, #e0f2fe 100%);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

.solution-icon svg {
    width: 28px;
    height: 28px;
    color: var(--primary);
}

.solution-card h3 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 10px;
}

.solution-card p {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 16px;
}

.solution-features {
    list-style: none;
}

.solution-features li {
    font-size: 0.85rem;
    color: var(--text-body);
    padding: 6px 0;
    padding-left: 20px;
    position: relative;
}

.solution-features li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--primary);
    font-weight: 600;
}

.solutions-more {
    text-align: center;
    margin-top: 40px;
    color: var(--text-muted);
}

.solutions-more span {
    display: inline-block;
    padding: 6px 14px;
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: 20px;
    margin: 4px;
    font-size: 0.85rem;
}

/* IOT+行业应用 */
.iot {
    background: var(--bg-white);
}

.iot-block {
    margin-bottom: 60px;
    padding: 40px;
    background: var(--bg-light);
    border-radius: 16px;
    border: 1px solid var(--border);
}

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

.iot-header {
    margin-bottom: 32px;
}

.iot-header h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 8px;
}

.iot-header p {
    color: var(--text-muted);
}

.iot-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-bottom: 32px;
}

.iot-module {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 24px;
    transition: all 0.2s;
}

.iot-module:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow);
}

.module-icon {
    font-size: 1.75rem;
    margin-bottom: 12px;
}

.iot-module h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 8px;
}

.iot-module p {
    font-size: 0.85rem;
    color: var(--text-muted);
    line-height: 1.6;
}

.iot-values {
    display: flex;
    gap: 24px;
    justify-content: center;
}

.value-card {
    text-align: center;
    padding: 20px 32px;
    background: var(--bg-white);
    border-radius: 10px;
    border: 1px solid var(--border);
}

.value-number {
    display: block;
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 4px;
}

.value-label {
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* 自研产品 */
.products {
    background: var(--bg-light);
}

.product-card {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    background: var(--bg-white);
    border-radius: 16px;
    border: 1px solid var(--border);
    padding: 48px;
    align-items: center;
}

.product-badge {
    display: inline-block;
    padding: 6px 14px;
    background: var(--primary);
    color: white;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 500;
    margin-bottom: 16px;
}

.product-content h3 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 8px;
}

.product-tagline {
    font-size: 1.1rem;
    color: var(--text-muted);
    margin-bottom: 16px;
}

.product-desc {
    color: var(--text-body);
    margin-bottom: 28px;
    line-height: 1.8;
}

.product-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 28px;
}

.pf-item {
    display: flex;
    gap: 12px;
}

.pf-icon {
    font-size: 1.5rem;
    flex-shrink: 0;
}

.pf-item h4 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 4px;
}

.pf-item p {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.product-tags {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.product-tags span {
    padding: 6px 14px;
    background: var(--bg-light);
    border: 1px solid var(--border);
    border-radius: 20px;
    font-size: 0.85rem;
    color: var(--text-body);
}

.product-image {
    display: flex;
    justify-content: center;
}

.phone-mockup {
    width: 260px;
    height: 520px;
    background: #1f2937;
    border-radius: 36px;
    padding: 8px;
    box-shadow: var(--shadow-xl);
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: var(--bg-white);
    border-radius: 28px;
    overflow: hidden;
}

.screen-header {
    background: var(--primary);
    color: white;
    padding: 40px 20px 20px;
    text-align: center;
    font-weight: 600;
}

.screen-map {
    height: 180px;
    background: var(--bg-light);
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0 30px;
}

.map-point {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    position: relative;
    z-index: 2;
}

.map-point.start {
    background: #22c55e;
}

.map-point.current {
    background: var(--primary);
    box-shadow: 0 0 0 4px rgba(26, 86, 219, 0.3);
}

.map-point.end {
    background: #ef4444;
}

.map-line {
    flex: 1;
    height: 3px;
    background: var(--primary);
}

.map-line-dashed {
    flex: 1;
    height: 3px;
    background: repeating-linear-gradient(
        90deg,
        var(--border) 0,
        var(--border) 8px,
        transparent 8px,
        transparent 16px
    );
}

.screen-info {
    padding: 20px;
}

.info-row {
    display: flex;
    justify-content: space-between;
    padding: 10px 0;
    border-bottom: 1px solid var(--border);
    font-size: 0.85rem;
}

.info-row:last-child {
    border-bottom: none;
}

.info-row .label {
    color: var(--text-muted);
}

.info-row .value {
    font-weight: 500;
    color: var(--text-dark);
}

.info-row .value.highlight {
    color: var(--primary);
}

/* 典型案例 */
.cases {
    background: var(--bg-white);
}

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

.case-card {
    background: var(--bg-light);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 28px;
    transition: all 0.2s;
}

.case-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow);
}

.case-header {
    margin-bottom: 16px;
}

.case-tag {
    display: inline-block;
    padding: 4px 10px;
    background: var(--primary);
    color: white;
    border-radius: 4px;
    font-size: 0.7rem;
    font-weight: 600;
    margin-bottom: 12px;
}

.case-header h3 {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text-dark);
}

.case-list {
    list-style: none;
}

.case-list li {
    font-size: 0.85rem;
    color: var(--text-body);
    padding: 8px 0;
    padding-left: 18px;
    position: relative;
}

.case-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 14px;
    width: 6px;
    height: 6px;
    background: var(--primary);
    border-radius: 50%;
}

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

.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
}

.contact-list {
    margin-top: 32px;
}

.contact-item {
    display: flex;
    gap: 16px;
    margin-bottom: 24px;
}

.contact-icon {
    width: 48px;
    height: 48px;
    background: var(--primary);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

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

.contact-item h4 {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 4px;
}

.contact-item p {
    font-weight: 500;
    color: var(--text-dark);
}

.contact-item a {
    color: var(--text-dark);
    text-decoration: none;
}

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

.cta-box {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 40px;
    text-align: center;
}

.cta-box h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 16px;
}

.cta-box p {
    color: var(--text-body);
    margin-bottom: 28px;
    line-height: 1.8;
}

/* 页脚 */
.footer {
    background: #1f2937;
    color: white;
    padding: 60px 24px 24px;
}

.footer-top {
    display: flex;
    justify-content: space-between;
    margin-bottom: 40px;
}

.footer-brand .logo {
    margin-bottom: 12px;
}

.footer-brand .logo-text {
    color: white;
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.9rem;
}

.footer-links {
    display: flex;
    gap: 60px;
}

.footer-col h4 {
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 16px;
}

.footer-col a {
    display: block;
    color: rgba(255, 255, 255, 0.6);
    text-decoration: none;
    font-size: 0.85rem;
    margin-bottom: 10px;
    transition: color 0.2s;
}

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

.footer-bottom {
    text-align: center;
    padding-top: 24px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom p {
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.85rem;
    margin-bottom: 8px;
}

.footer-bottom p:last-child {
    margin-bottom: 0;
}

.footer-bottom a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: color 0.3s ease;
}

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

/* 响应式设计 */
@media (max-width: 1024px) {
    .solutions-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

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

    .footer-links {
        gap: 40px;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 64px;
        left: 0;
        right: 0;
        background: var(--bg-white);
        border-bottom: 1px solid var(--border);
        flex-direction: column;
        padding: 24px;
        gap: 16px;
        transform: translateY(-100%);
        opacity: 0;
        transition: all 0.3s;
        pointer-events: none;
    }

    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        pointer-events: auto;
    }

    .nav-toggle {
        display: flex;
    }

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

    .hero-image {
        display: none;
    }

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

    .solutions-grid {
        grid-template-columns: 1fr;
    }

    .iot-grid {
        grid-template-columns: 1fr;
    }

    .iot-values {
        flex-direction: column;
        align-items: center;
    }

    .product-card {
        grid-template-columns: 1fr;
        padding: 32px;
    }

    .product-image {
        order: -1;
    }

    .phone-mockup {
        width: 220px;
        height: 440px;
    }

    .product-features {
        grid-template-columns: 1fr;
    }

    .cases-grid {
        grid-template-columns: 1fr;
    }

    .contact-wrapper {
        grid-template-columns: 1fr;
    }

    .footer-top {
        flex-direction: column;
        gap: 32px;
    }

    .footer-links {
        flex-wrap: wrap;
        gap: 32px;
    }
}

@media (max-width: 480px) {
    .section {
        padding: 60px 16px;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .btn-lg {
        width: 100%;
    }

    .hero-features {
        flex-direction: column;
    }

    .iot-block {
        padding: 24px;
    }
}