/* ========================================
   全局样式与变量
   ======================================== */
:root {
    --primary: #3B82F6;
    --primary-dark: #2563EB;
    --primary-light: #60A5FA;
    --secondary: #0F172A;
    --cta: #F97316;
    --cta-hover: #EA580C;
    --background: #F8FAFC;
    --background-alt: #F1F5F9;
    --text: #1E293B;
    --text-muted: #64748B;
    --text-light: #94A3B8;
    --border: #E2E8F0;
    --white: #FFFFFF;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --radius: 12px;
    --radius-lg: 16px;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--text);
    background-color: var(--background);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

ul {
    list-style: none;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ========================================
   按钮样式
   ======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 32px;
    font-size: 16px;
    font-weight: 600;
    border-radius: var(--radius);
    cursor: pointer;
    transition: var(--transition);
    border: none;
    outline: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--cta) 0%, var(--cta-hover) 100%);
    color: var(--white);
    box-shadow: 0 4px 14px 0 rgba(249, 115, 22, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px 0 rgba(249, 115, 22, 0.5);
}

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

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

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

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

/* ========================================
   导航栏
   ======================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.navbar.scrolled {
    box-shadow: var(--shadow);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 700;
    color: var(--secondary);
}

.logo svg {
    width: 36px;
    height: 36px;
    color: var(--primary);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-links a {
    font-size: 15px;
    font-weight: 500;
    color: var(--text);
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
}

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

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

.nav-cta {
    display: flex;
    align-items: center;
    gap: 16px;
}

.nav-cta .btn {
    padding: 10px 24px;
    font-size: 14px;
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 8px;
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--secondary);
    transition: var(--transition);
}

/* ========================================
   英雄区
   ======================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 120px 0 80px;
    background: linear-gradient(135deg, #0F172A 0%, #1E293B 50%, #334155 100%);
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('../images/bg.jpg') center/cover no-repeat;
    opacity: 0.15;
}

.hero::after {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 80%;
    height: 200%;
    background: radial-gradient(ellipse, rgba(59, 130, 246, 0.15) 0%, transparent 70%);
    pointer-events: none;
}

.hero .container {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-content {
    color: var(--white);
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    background: rgba(59, 130, 246, 0.2);
    border: 1px solid rgba(59, 130, 246, 0.3);
    border-radius: 50px;
    font-size: 14px;
    color: var(--primary-light);
    margin-bottom: 24px;
}

.hero-badge svg {
    width: 16px;
    height: 16px;
}

.hero h1 {
    font-size: 48px;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 24px;
}

.hero h1 span {
    background: linear-gradient(135deg, var(--primary-light) 0%, var(--cta) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-description {
    font-size: 18px;
    line-height: 1.8;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 32px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    margin-bottom: 48px;
}

.hero-stats {
    display: flex;
    gap: 48px;
}

.stat-item {
    text-align: left;
}

.stat-number {
    font-size: 36px;
    font-weight: 800;
    color: var(--white);
    line-height: 1;
    margin-bottom: 4px;
}

.stat-label {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.6);
}

.hero-image {
    position: relative;
}

.hero-image img {
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
}

.hero-image::before {
    content: '';
    position: absolute;
    top: -20px;
    right: -20px;
    width: 100%;
    height: 100%;
    border: 2px solid var(--primary);
    border-radius: var(--radius-lg);
    z-index: -1;
}

/* ========================================
   功能特点区
   ======================================== */
.features {
    padding: 100px 0;
    background: var(--white);
}

.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 60px;
}

.section-tag {
    display: inline-block;
    padding: 6px 16px;
    background: rgba(59, 130, 246, 0.1);
    color: var(--primary);
    font-size: 14px;
    font-weight: 600;
    border-radius: 50px;
    margin-bottom: 16px;
}

.section-title {
    font-size: 40px;
    font-weight: 800;
    color: var(--secondary);
    margin-bottom: 16px;
    line-height: 1.2;
}

.section-description {
    font-size: 18px;
    color: var(--text-muted);
    line-height: 1.7;
}

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

.feature-card {
    padding: 32px;
    background: var(--background);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    transition: var(--transition);
    cursor: pointer;
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
}

.feature-icon {
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    border-radius: var(--radius);
    margin-bottom: 20px;
}

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

.feature-card h3 {
    font-size: 18px;
    font-weight: 700;
    color: var(--secondary);
    margin-bottom: 12px;
}

.feature-card p {
    font-size: 15px;
    color: var(--text-muted);
    line-height: 1.6;
}

/* ========================================
   价值主张区
   ======================================== */
.value-proposition {
    padding: 100px 0;
    background: linear-gradient(180deg, var(--background) 0%, var(--white) 100%);
}

.value-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.value-content h2 {
    font-size: 36px;
    font-weight: 800;
    color: var(--secondary);
    margin-bottom: 24px;
    line-height: 1.3;
}

.value-content p {
    font-size: 17px;
    color: var(--text-muted);
    line-height: 1.8;
    margin-bottom: 32px;
}

.value-list {
    display: flex;
    flex-direction: column;
    gap: 20px;
    margin-bottom: 32px;
}

.value-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
}

.value-item-icon {
    flex-shrink: 0;
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(59, 130, 246, 0.1);
    border-radius: 50%;
    color: var(--primary);
}

.value-item-icon svg {
    width: 14px;
    height: 14px;
}

.value-item-text h4 {
    font-size: 16px;
    font-weight: 600;
    color: var(--secondary);
    margin-bottom: 4px;
}

.value-item-text p {
    font-size: 15px;
    color: var(--text-muted);
    margin-bottom: 0;
}

.value-image {
    position: relative;
}

.value-image img {
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
}

.value-image-badge {
    position: absolute;
    bottom: -20px;
    left: -20px;
    padding: 20px 24px;
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: 12px;
}

.value-image-badge svg {
    width: 40px;
    height: 40px;
    color: var(--cta);
}

.value-image-badge span {
    font-size: 14px;
    font-weight: 600;
    color: var(--secondary);
}

/* ========================================
   关于我们
   ======================================== */
.about {
    padding: 100px 0;
    background: var(--secondary);
    color: var(--white);
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.about-image img {
    border-radius: var(--radius-lg);
}

.about-content .section-tag {
    background: rgba(59, 130, 246, 0.2);
}

.about-content h2 {
    font-size: 36px;
    font-weight: 800;
    margin-bottom: 24px;
    line-height: 1.3;
}

.about-content p {
    font-size: 17px;
    color: rgba(255, 255, 255, 0.8);
    line-height: 1.8;
    margin-bottom: 20px;
}

.about-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    margin-top: 32px;
}

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

.about-feature svg {
    width: 20px;
    height: 20px;
    color: var(--primary-light);
}

.about-feature span {
    font-size: 15px;
    font-weight: 500;
}

/* ========================================
   用户评价
   ======================================== */
.testimonials {
    padding: 100px 0;
    background: var(--white);
}

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

.testimonial-card {
    padding: 32px;
    background: var(--background);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    transition: var(--transition);
}

.testimonial-card:hover {
    box-shadow: var(--shadow-lg);
}

.testimonial-rating {
    display: flex;
    gap: 4px;
    margin-bottom: 20px;
}

.testimonial-rating svg {
    width: 20px;
    height: 20px;
    color: #FBBF24;
    fill: #FBBF24;
}

.testimonial-content {
    font-size: 16px;
    color: var(--text);
    line-height: 1.7;
    margin-bottom: 24px;
}

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

.testimonial-avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-size: 18px;
    font-weight: 700;
}

.testimonial-info h4 {
    font-size: 16px;
    font-weight: 600;
    color: var(--secondary);
    margin-bottom: 2px;
}

.testimonial-info p {
    font-size: 14px;
    color: var(--text-muted);
}

/* ========================================
   服务内容区
   ======================================== */
.services {
    padding: 100px 0;
    background: var(--background);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
}

.service-card {
    display: flex;
    gap: 24px;
    padding: 32px;
    background: var(--white);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    transition: var(--transition);
    cursor: pointer;
}

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

.service-image {
    flex-shrink: 0;
    width: 200px;
    height: 150px;
    border-radius: var(--radius);
    overflow: hidden;
}

.service-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.service-content {
    flex: 1;
}

.service-content h3 {
    font-size: 20px;
    font-weight: 700;
    color: var(--secondary);
    margin-bottom: 12px;
}

.service-content p {
    font-size: 15px;
    color: var(--text-muted);
    line-height: 1.7;
    margin-bottom: 16px;
}

.service-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 15px;
    font-weight: 600;
    color: var(--primary);
}

.service-link svg {
    width: 16px;
    height: 16px;
    transition: var(--transition);
}

.service-link:hover svg {
    transform: translateX(4px);
}

/* ========================================
   常见问题
   ======================================== */
.faq {
    padding: 100px 0;
    background: var(--white);
}

.faq-grid {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    border-bottom: 1px solid var(--border);
}

.faq-question {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 24px 0;
    cursor: pointer;
    transition: var(--transition);
}

.faq-question:hover {
    color: var(--primary);
}

.faq-question h3 {
    font-size: 18px;
    font-weight: 600;
    color: inherit;
}

.faq-question svg {
    width: 24px;
    height: 24px;
    color: var(--text-muted);
    transition: var(--transition);
    flex-shrink: 0;
}

.faq-item.active .faq-question svg {
    transform: rotate(180deg);
    color: var(--primary);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-answer p {
    padding-bottom: 24px;
    font-size: 16px;
    color: var(--text-muted);
    line-height: 1.7;
}

.faq-item.active .faq-answer {
    max-height: 500px;
}

/* ========================================
   CTA区
   ======================================== */
.cta-section {
    padding: 100px 0;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    text-align: center;
    color: var(--white);
}

.cta-section h2 {
    font-size: 40px;
    font-weight: 800;
    margin-bottom: 20px;
}

.cta-section p {
    font-size: 18px;
    opacity: 0.9;
    margin-bottom: 32px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.cta-section .btn-primary {
    background: var(--white);
    color: var(--primary);
    box-shadow: 0 4px 14px 0 rgba(0, 0, 0, 0.2);
}

.cta-section .btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px 0 rgba(0, 0, 0, 0.3);
}

/* ========================================
   页脚
   ======================================== */
.footer {
    padding: 80px 0 24px;
    background: var(--secondary);
    color: var(--white);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 48px;
    margin-bottom: 48px;
}

.footer-brand p {
    font-size: 15px;
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.7;
    margin-top: 20px;
    margin-bottom: 24px;
}

.footer-social {
    display: flex;
    gap: 12px;
}

.footer-social a {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    transition: var(--transition);
}

.footer-social a:hover {
    background: var(--primary);
}

.footer-social svg {
    width: 20px;
    height: 20px;
}

.footer-column h4 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 24px;
}

.footer-column ul {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.footer-column a {
    font-size: 15px;
    color: rgba(255, 255, 255, 0.7);
}

.footer-column a:hover {
    color: var(--white);
}

.footer-bottom {
    padding-top: 24px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 16px;
}

.footer-copyright {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.6);
}

.footer-links {
    display: flex;
    gap: 24px;
}

.footer-links a {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.6);
}

.footer-links a:hover {
    color: var(--white);
}

/* ========================================
   移动端菜单
   ======================================== */
.mobile-menu {
    display: none;
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--white);
    padding: 24px;
    box-shadow: var(--shadow-lg);
    z-index: 999;
}

.mobile-menu.active {
    display: block;
}

.mobile-menu a {
    display: block;
    padding: 12px 0;
    font-size: 16px;
    font-weight: 500;
    color: var(--text);
    border-bottom: 1px solid var(--border);
}

.mobile-menu .btn {
    width: 100%;
    margin-top: 16px;
}

/* ========================================
   响应式设计
   ======================================== */
@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-content {
        order: 1;
    }
    
    .hero-image {
        order: 2;
        max-width: 500px;
        margin: 0 auto;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .hero-stats {
        justify-content: center;
    }
    
    .value-grid,
    .about-grid {
        grid-template-columns: 1fr;
        gap: 48px;
    }
    
    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .nav-links,
    .nav-cta {
        display: none;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .hero {
        padding: 100px 0 60px;
    }
    
    .hero h1 {
        font-size: 32px;
    }
    
    .hero-description {
        font-size: 16px;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .hero-stats {
        flex-wrap: wrap;
        gap: 24px;
    }
    
    .stat-number {
        font-size: 28px;
    }
    
    .section-title {
        font-size: 28px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .testimonials-grid {
        grid-template-columns: 1fr;
    }
    
    .services-grid {
        grid-template-columns: 1fr;
    }
    
    .service-card {
        flex-direction: column;
    }
    
    .service-image {
        width: 100%;
        height: 200px;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }
    
    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }
    
    .about-features {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }
    
    .hero h1 {
        font-size: 28px;
    }
    
    .section-title {
        font-size: 24px;
    }
    
    .btn {
        padding: 12px 24px;
        font-size: 15px;
    }
    
    .feature-card,
    .testimonial-card,
    .service-card {
        padding: 24px;
    }
}

/* ========================================
   动画效果
   ======================================== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fadeInUp {
    animation: fadeInUp 0.6s ease forwards;
}

.delay-100 { animation-delay: 0.1s; }
.delay-200 { animation-delay: 0.2s; }
.delay-300 { animation-delay: 0.3s; }
.delay-400 { animation-delay: 0.4s; }

/* ========================================
   滚动动画
   ======================================== */
.scroll-animate {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.scroll-animate.visible {
    opacity: 1;
    transform: translateY(0);
}