/* ========================================
   至强网络官网 - 全局样式
   ======================================== */

/* === CSS Reset & Base === */
* {
    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', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

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

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

ul {
    list-style: none;
}

/* === Navigation === */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    padding: 1rem 0;
}

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

.nav-brand a {
    font-size: 1.5rem;
    font-weight: 700;
    color: #0066CC;
}

.nav-brand span {
    color: #333;
}

.nav-menu {
    display: flex;
    gap: 2rem;
}

.nav-menu a {
    font-weight: 500;
    color: #333;
    transition: color 0.3s ease;
    position: relative;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: #0066CC;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: #0066CC;
    transition: width 0.3s ease;
}

.nav-menu a:hover::after,
.nav-menu a.active::after {
    width: 100%;
}

.burger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
}

.burger div {
    width: 25px;
    height: 3px;
    background: #333;
    transition: all 0.3s ease;
}

/* === Hero Section === */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #0066CC 0%, #004499 100%);
    color: white;
    padding-top: 80px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 3rem;
    opacity: 0.95;
}

.hero-buttons {
    display: flex;
    gap: 1.5rem;
}

.btn {
    padding: 1rem 2.5rem;
    border-radius: 8px;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
}

.btn-primary {
    background: #FF6600;
    color: white;
    border: 2px solid #FF6600;
}

.btn-primary:hover {
    background: transparent;
    color: white;
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid white;
}

.btn-secondary:hover {
    background: white;
    color: #0066CC;
}

/* === Section Styling === */
section {
    padding: 80px 0;
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 1rem;
    color: #333;
    font-weight: 700;
}

.section-subtitle {
    text-align: center;
    font-size: 1.2rem;
    color: #666;
    margin-bottom: 3rem;
}

/* === Services Section === */
.services {
    background: #f8f9fa;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.service-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
}

.service-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
}

.service-card .icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.service-card h3 {
    font-size: 1.3rem;
    margin-bottom: 0.8rem;
    color: #333;
}

.service-card p {
    color: #666;
    font-size: 0.95rem;
}

/* === Stats Section === */
.stats {
    background: #333;
    color: white;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    text-align: center;
}

.stat-number {
    font-size: 3rem;
    font-weight: 800;
    color: #0066CC;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* === About Section === */
.about {
    background: #fff;
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
}

.about-text p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    line-height: 1.8;
}

.features-list {
    margin-bottom: 2rem;
}

.features-list li {
    font-size: 1.1rem;
    margin-bottom: 0.8rem;
}

blockquote {
    font-size: 1.3rem;
    font-style: italic;
    color: #0066CC;
    border-left: 4px solid #0066CC;
    padding-left: 1.5rem;
    margin-left: 0;
}

/* === Solutions Section === */
.solutions {
    background: #f8f9fa;
}

.solutions-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 2rem;
}

.solution-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
}

.solution-card h3 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
    color: #0066CC;
}

.solution-card > p {
    margin-bottom: 1rem;
}

.solution-card ul {
    margin: 1rem 0;
    padding-left: 1.5rem;
}

.solution-card ul li {
    margin-bottom: 0.5rem;
    position: relative;
}

.solution-card ul li::before {
    content: "•";
    color: #0066CC;
    font-weight: bold;
    position: absolute;
    left: -1.5rem;
}

/* === Cases Section === */
.cases {
    background: #fff;
}

.cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.case-card {
    background: #f8f9fa;
    padding: 2rem;
    border-radius: 12px;
    border-left: 4px solid #0066CC;
}

.case-card h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: #333;
}

.case-problem, .case-solution, .case-result {
    margin-bottom: 1rem;
}

.case-problem strong, .case-solution strong, .case-result strong {
    display: block;
    margin-bottom: 0.5rem;
    color: #0066CC;
}

.case-result ul {
    padding-left: 1.5rem;
}

.case-result ul li {
    margin-bottom: 0.3rem;
}

.testimonial {
    background: #e8f4fd;
    padding: 2rem;
    border-radius: 12px;
    font-size: 1.2rem;
    font-style: italic;
    margin-top: 3rem;
    text-align: center;
}

/* === AI Section === */
.ai {
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    color: white;
}

.ai .section-title {
    color: white;
}

.tech-stack {
    text-align: center;
    font-size: 1.3rem;
    margin-bottom: 3rem;
    opacity: 0.9;
}

.ai-highlights {
    margin-bottom: 4rem;
}

.ai-highlight-box {
    text-align: center;
    margin-bottom: 3rem;
}

.ai-highlight-box h3 {
    font-size: 2rem;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, #00d4ff 0%, #0066CC 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.ai-highlight-box p {
    font-size: 1.2rem;
    opacity: 0.9;
}

.ai-feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
}

.ai-feature-card {
    background: rgba(255, 255, 255, 0.08);
    padding: 2rem;
    border-radius: 16px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all 0.4s ease;
    position: relative;
    overflow: hidden;
}

.ai-feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, #00d4ff 0%, #0066CC 100%);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.4s ease;
}

.ai-feature-card:hover {
    transform: translateY(-8px);
    background: rgba(255, 255, 255, 0.12);
    box-shadow: 0 20px 40px rgba(0, 212, 255, 0.2);
}

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

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.ai-feature-card h4 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: #00d4ff;
}

.ai-feature-card > p {
    font-size: 1rem;
    opacity: 0.85;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.feature-list {
    margin-top: 1rem;
}

.feature-list li {
    font-size: 0.95rem;
    margin-bottom: 0.7rem;
    opacity: 0.9;
    padding-left: 1.5rem;
    position: relative;
}

.feature-list li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: #00d4ff;
    font-weight: bold;
}

/* AI Steps Section */
.ai-steps {
    margin-top: 4rem;
}

.ai-steps h3 {
    text-align: center;
    font-size: 1.8rem;
    margin-bottom: 3rem;
    color: white;
}

.steps-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 1.5rem;
}

.step-item {
    flex: 1;
    min-width: 200px;
    max-width: 250px;
    text-align: center;
}

.step-number {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, #00d4ff 0%, #0066CC 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    font-size: 1.5rem;
    font-weight: 800;
    box-shadow: 0 8px 20px rgba(0, 212, 255, 0.3);
}

.step-content h4 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: #00d4ff;
}

.step-content p {
    font-size: 0.95rem;
    opacity: 0.8;
}

.step-arrow {
    font-size: 2rem;
    color: #00d4ff;
    opacity: 0.7;
    flex-shrink: 0;
}

@media (max-width: 768px) {
    .steps-container {
        flex-direction: column;
    }
    
    .step-arrow {
        transform: rotate(90deg);
        margin: 0.5rem 0;
    }
    
    .ai-feature-grid {
        grid-template-columns: 1fr;
    }
}

/* === Contact Section === */
.contact {
    background: #f8f9fa;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    max-width: 900px;
    margin: 0 auto;
}

.info-item {
    margin-bottom: 1.5rem;
    display: flex;
    flex-direction: column;
}

.info-item .label {
    font-weight: 600;
    color: #0066CC;
    margin-bottom: 0.3rem;
}

.info-item .value {
    font-size: 1.1rem;
}

.bank-info {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
}

.bank-info h4 {
    font-size: 1.3rem;
    margin-bottom: 1.5rem;
    color: #333;
}

.bank-details p {
    margin-bottom: 0.8rem;
    font-size: 1rem;
}

/* === Footer === */
.footer {
    background: #333;
    color: white;
    text-align: center;
    padding: 2rem 0;
}

.footer a {
    color: #0066CC;
}

/* === Scroll to Top Button === */
.scroll-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: #0066CC;
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 1.5rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0, 102, 204, 0.4);
}

.scroll-top.visible {
    opacity: 1;
    visibility: visible;
}

.scroll-top:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 20px rgba(0, 102, 204, 0.6);
}

/* === Responsive Design === */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background: white;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .burger {
        display: flex;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
    }

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

    .btn {
        padding: 0.8rem 2rem;
    }

    .section-title {
        font-size: 1.8rem;
    }

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

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

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

    .stat-number {
        font-size: 2rem;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.6rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .service-card {
        padding: 1.5rem;
    }
}