/* 全局样式 */
:root {
    --primary-color: #0F4C99;
    --secondary-color: #40A0FF;
    --text-color: #333;
    --bg-color: #ffffff;
    --bg-secondary: #f5f7fa;
    --border-color: #e1e8ed;
    --shadow: 0 2px 12px rgba(15, 76, 153, 0.08);
    --shadow-hover: 0 4px 20px rgba(15, 76, 153, 0.15);
}

[data-theme="dark"] {
    --text-color: #e1e8ed;
    --bg-color: #0a0e1a;
    --bg-secondary: #151b2d;
    --border-color: #2a3447;
    --shadow: 0 2px 12px rgba(0, 0, 0, 0.3);
    --shadow-hover: 0 4px 20px rgba(64, 160, 255, 0.2);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Source Han Sans CN', 'Noto Sans SC', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    transition: background-color 0.3s ease, color 0.3s ease;
}

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

/* 主题切换按钮 */
.theme-toggle {
    position: fixed;
    top: 80px;
    right: 30px;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: var(--primary-color);
    border: none;
    cursor: pointer;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
}

.theme-toggle:hover {
    transform: scale(1.1);
    box-shadow: var(--shadow-hover);
}

.theme-icon {
    font-size: 24px;
}

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: var(--bg-color);
    box-shadow: var(--shadow);
    z-index: 999;
    transition: all 0.3s ease;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
}

.nav-brand {
    font-size: 24px;
    font-weight: bold;
    color: var(--primary-color);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-link {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--secondary-color);
    transition: width 0.3s ease;
}

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

.nav-link:hover,
.nav-link.active {
    color: var(--secondary-color);
}

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

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: var(--text-color);
    transition: all 0.3s ease;
}

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

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--primary-color) 0%, #1a5fb4 50%, var(--secondary-color) 100%);
    opacity: 0.9;
}

.hero-background::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image:
        repeating-linear-gradient(0deg, transparent, transparent 50px, rgba(64, 160, 255, 0.1) 50px, rgba(64, 160, 255, 0.1) 51px),
        repeating-linear-gradient(90deg, transparent, transparent 50px, rgba(64, 160, 255, 0.1) 50px, rgba(64, 160, 255, 0.1) 51px);
    animation: grid-move 20s linear infinite;
}

@keyframes grid-move {
    0% { transform: translate(0, 0); }
    100% { transform: translate(50px, 50px); }
}

.hero-content {
    position: relative;
    z-index: 2;
    color: white;
}

.hero-title {
    font-size: 48px;
    font-weight: bold;
    margin-bottom: 20px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
    font-size: 20px;
    margin-bottom: 40px;
    opacity: 0.95;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
}

.btn {
    display: inline-block;
    padding: 12px 32px;
    text-decoration: none;
    border-radius: 5px;
    font-weight: 500;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

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

.btn-primary:hover {
    background: var(--secondary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(64, 160, 255, 0.4);
}

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

.btn-secondary:hover {
    background: white;
    color: var(--primary-color);
    transform: translateY(-2px);
}

.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
}

.scroll-indicator span {
    display: block;
    width: 20px;
    height: 30px;
    border: 2px solid white;
    border-radius: 15px;
    position: relative;
}

.scroll-indicator span::before {
    content: '';
    position: absolute;
    top: 5px;
    left: 50%;
    transform: translateX(-50%);
    width: 4px;
    height: 8px;
    background: white;
    border-radius: 2px;
    animation: scroll 1.5s infinite;
}

@keyframes scroll {
    0%, 100% { transform: translate(-50%, 0); opacity: 1; }
    50% { transform: translate(-50%, 10px); opacity: 0.5; }
}

/* 三大优势 */
.advantages {
    padding: 80px 0;
    background: var(--bg-secondary);
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.advantage-card {
    background: var(--bg-color);
    padding: 40px 30px;
    border-radius: 10px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
}

.advantage-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.advantage-icon {
    font-size: 48px;
    margin-bottom: 20px;
}

.advantage-card h3 {
    font-size: 24px;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.advantage-card p {
    color: var(--text-color);
    line-height: 1.8;
}

/* CTA Banner */
.cta-banner {
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    padding: 40px 0;
    text-align: center;
}

.cta-banner .container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 30px;
    flex-wrap: wrap;
}

.cta-text {
    color: white;
    font-size: 18px;
    margin: 0;
}

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

.cta-banner .btn:hover {
    background: var(--bg-secondary);
}

/* 通用 Section */
.section {
    padding: 80px 0;
}

.section:nth-child(odd) {
    background: var(--bg-secondary);
}

.section-title {
    font-size: 36px;
    text-align: center;
    color: var(--primary-color);
    margin-bottom: 50px;
    position: relative;
    padding-bottom: 15px;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: var(--secondary-color);
}

/* 关于我们 */
.about-content {
    max-width: 900px;
    margin: 0 auto;
}

.about-text h3 {
    font-size: 24px;
    color: var(--primary-color);
    margin: 30px 0 15px;
}

.about-text p {
    font-size: 16px;
    line-height: 1.8;
    margin-bottom: 20px;
}

.highlight {
    font-size: 20px;
    font-weight: bold;
    color: var(--secondary-color);
    text-align: center;
    padding: 20px;
    margin-top: 30px;
}

.core-advantages {
    margin-top: 50px;
}

.advantage-list {
    display: grid;
    gap: 25px;
    margin-top: 20px;
}

.advantage-item {
    background: var(--bg-color);
    padding: 25px;
    border-radius: 8px;
    border-left: 4px solid var(--secondary-color);
    box-shadow: var(--shadow);
}

.advantage-item h4 {
    font-size: 18px;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.advantage-item p {
    color: var(--text-color);
    line-height: 1.8;
}

/* 核心业务 */
.business-blocks {
    display: grid;
    gap: 40px;
}

.business-block {
    background: var(--bg-color);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.business-header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 25px 30px;
}

.business-header h3 {
    font-size: 24px;
}

.business-services {
    padding: 30px;
    display: grid;
    gap: 25px;
}

.service-item {
    padding: 20px;
    border-left: 3px solid var(--secondary-color);
    background: var(--bg-secondary);
    border-radius: 5px;
}

.service-item h4 {
    font-size: 18px;
    color: var(--primary-color);
    margin-bottom: 12px;
}

.service-item ul {
    list-style: none;
    padding-left: 0;
}

.service-item li {
    padding: 6px 0;
    padding-left: 20px;
    position: relative;
}

.service-item li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--secondary-color);
}

.service-item p {
    line-height: 1.8;
    color: var(--text-color);
}

/* 团队实力 */
.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

.team-card {
    background: var(--bg-color);
    padding: 40px 30px;
    border-radius: 10px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
}

.team-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.team-icon {
    font-size: 48px;
    margin-bottom: 20px;
}

.team-card h3 {
    font-size: 20px;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.team-count {
    font-size: 24px;
    font-weight: bold;
    color: var(--secondary-color);
    margin: 15px 0;
}

.team-card p {
    line-height: 1.8;
    color: var(--text-color);
}

.team-summary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 30px;
    border-radius: 10px;
    text-align: center;
    font-size: 18px;
    line-height: 1.8;
}

/* 项目案例 */
.cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
}

.case-card {
    background: var(--bg-color);
    padding: 30px;
    border-radius: 10px;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
}

.case-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.case-category {
    display: inline-block;
    background: var(--secondary-color);
    color: white;
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 14px;
    margin-bottom: 15px;
}

.case-card h3 {
    font-size: 20px;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.case-desc {
    line-height: 1.8;
    color: var(--text-color);
    margin-bottom: 15px;
}

.case-result {
    font-weight: bold;
    color: var(--secondary-color);
    margin-top: 15px;
}

.case-highlight {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-top: 15px;
}

.case-highlight span {
    background: var(--bg-secondary);
    color: var(--primary-color);
    padding: 5px 12px;
    border-radius: 5px;
    font-size: 14px;
}

/* 联系我们 */
.contact-content {
    max-width: 900px;
    margin: 0 auto;
}

.contact-info {
    display: grid;
    gap: 30px;
    margin-bottom: 50px;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 20px;
    background: var(--bg-color);
    padding: 25px;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.contact-icon {
    font-size: 36px;
    min-width: 50px;
}

.contact-item h4 {
    font-size: 18px;
    color: var(--primary-color);
    margin-bottom: 5px;
}

.contact-item p {
    font-size: 16px;
    color: var(--text-color);
}

.compliance-notice {
    background: var(--bg-color);
    padding: 30px;
    border-radius: 10px;
    border: 2px solid var(--secondary-color);
    box-shadow: var(--shadow);
}

.compliance-notice h4 {
    font-size: 20px;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.compliance-notice p {
    line-height: 1.8;
    margin-bottom: 15px;
}

.compliance-notice ul {
    list-style: none;
    padding-left: 0;
}

.compliance-notice li {
    padding: 8px 0;
    line-height: 1.6;
}

/* 页脚 */
.footer {
    background: var(--bg-secondary);
    padding: 30px 0;
    text-align: center;
    border-top: 1px solid var(--border-color);
}

.footer-text {
    font-size: 16px;
    color: var(--text-color);
    margin-bottom: 10px;
}

.footer-備案 {
    font-size: 14px;
    color: var(--text-color);
    opacity: 0.7;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 60px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 60px);
        background: var(--bg-color);
        flex-direction: column;
        align-items: center;
        justify-content: flex-start;
        padding-top: 50px;
        gap: 20px;
        transition: left 0.3s ease;
        box-shadow: var(--shadow);
    }

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

    .nav-toggle {
        display: flex;
    }

    .nav-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(8px, 8px);
    }

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

    .nav-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -7px);
    }

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

    .hero-subtitle {
        font-size: 16px;
    }

    .hero-buttons {
        flex-direction: column;
        gap: 15px;
    }

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

    .section-title {
        font-size: 28px;
    }

    .theme-toggle {
        top: 70px;
        right: 20px;
        width: 45px;
        height: 45px;
    }

    .cta-banner .container {
        flex-direction: column;
        gap: 20px;
    }

    .contact-item {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .hero-title {
        font-size: 24px;
    }

    .hero-subtitle {
        font-size: 14px;
    }

    .section {
        padding: 50px 0;
    }

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