/* ========================================
   18jky.com - 极简黑白风企业官网样式
   ======================================== */

/* CSS Reset & Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
    background-color: #ffffff;
    color: #000000;
    line-height: 1.6;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

ul, ol {
    list-style: none;
}

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

/* 滚动条样式 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #f5f5f5;
}

::-webkit-scrollbar-thumb {
    background: #000;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #333;
}

/* ========================================
   顶部导航栏
   ======================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: transparent;
    transition: all 0.4s ease;
    padding: 20px 0;
}

.header.scrolled {
    background: #000;
    padding: 15px 0;
    box-shadow: 0 2px 20px rgba(0,0,0,0.3);
}

.header-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 28px;
    font-weight: 700;
    letter-spacing: 2px;
    color: #fff;
    text-transform: uppercase;
}

.logo span {
    color: #fff;
}

.nav-menu {
    display: flex;
    gap: 35px;
}

.nav-menu li a {
    color: #fff;
    font-size: 14px;
    font-weight: 500;
    letter-spacing: 1px;
    text-transform: uppercase;
    position: relative;
    padding: 8px 0;
}

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

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

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 5px;
}

.hamburger span {
    width: 28px;
    height: 2px;
    background: #fff;
    transition: all 0.3s ease;
}

.hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

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

.hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

/* 移动端导航 */
@media (max-width: 992px) {
    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: #000;
        flex-direction: column;
        padding: 80px 30px;
        gap: 25px;
        transition: right 0.4s ease;
    }

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

    .hamburger {
        display: flex;
    }
}

/* ========================================
   首页 Hero Section - 纵向卷轴展开
   ======================================== */
.hero-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #000;
    position: relative;
    overflow: hidden;
    padding: 100px 40px;
}

.hero-content {
    text-align: center;
    max-width: 900px;
    z-index: 2;
}

.hero-title {
    font-size: 64px;
    font-weight: 800;
    color: #fff;
    margin-bottom: 30px;
    letter-spacing: 3px;
    opacity: 0;
    transform: translateY(50px);
    animation: fadeUp 1s ease forwards 0.3s;
}

.hero-subtitle {
    font-size: 20px;
    color: #ccc;
    margin-bottom: 50px;
    line-height: 1.8;
    opacity: 0;
    transform: translateY(50px);
    animation: fadeUp 1s ease forwards 0.6s;
}

.hero-btn {
    display: inline-block;
    padding: 18px 50px;
    background: #fff;
    color: #000;
    font-size: 16px;
    font-weight: 600;
    letter-spacing: 2px;
    border: 2px solid #fff;
    transition: all 0.4s ease;
    opacity: 0;
    transform: translateY(50px);
    animation: fadeUp 1s ease forwards 0.9s;
}

.hero-btn:hover {
    background: transparent;
    color: #fff;
}

@keyframes fadeUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 动态背景线条 */
.hero-bg-lines {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.hero-bg-lines::before {
    content: '';
    position: absolute;
    width: 200%;
    height: 200%;
    top: -50%;
    left: -50%;
    background: repeating-linear-gradient(
        0deg,
        transparent,
        transparent 50px,
        rgba(255,255,255,0.03) 50px,
        rgba(255,255,255,0.03) 51px
    );
    animation: moveLines 20s linear infinite;
}

@keyframes moveLines {
    from { transform: translateY(0); }
    to { transform: translateY(-100px); }
}

/* ========================================
   通用 Section 样式
   ======================================== */
.section {
    padding: 120px 40px;
    max-width: 1400px;
    margin: 0 auto;
}

.section-header {
    text-align: center;
    margin-bottom: 80px;
}

.section-title {
    font-size: 42px;
    font-weight: 700;
    color: #000;
    margin-bottom: 20px;
    letter-spacing: 2px;
}

.section-subtitle {
    font-size: 16px;
    color: #666;
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.8;
}

/* ========================================
   核心优势板块 - 不对称网格布局
   ======================================== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
}

.feature-card {
    background: #f8f8f8;
    padding: 50px 35px;
    transition: all 0.4s ease;
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 0;
    background: #000;
    transition: height 0.4s ease;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
}

.feature-card:hover::before {
    height: 100%;
}

.feature-icon {
    width: 60px;
    height: 60px;
    margin-bottom: 25px;
}

.feature-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.feature-card h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 15px;
    color: #000;
}

.feature-card p {
    font-size: 14px;
    color: #666;
    line-height: 1.8;
}

/* 特殊卡片跨度 */
.feature-card:nth-child(1) {
    grid-column: span 2;
}

.feature-card:nth-child(6) {
    grid-column: span 2;
}

@media (max-width: 992px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .feature-card:nth-child(1),
    .feature-card:nth-child(6) {
        grid-column: span 1;
    }
}

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

/* ========================================
   快速入口板块 - 横向滚动
   ======================================== */
.quick-access {
    background: #000;
    padding: 100px 40px;
}

.access-container {
    max-width: 1400px;
    margin: 0 auto;
}

.access-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.access-item {
    position: relative;
    height: 300px;
    overflow: hidden;
    cursor: pointer;
}

.access-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.6s ease;
    filter: grayscale(100%);
}

.access-item:hover img {
    transform: scale(1.1);
    filter: grayscale(0%);
}

.access-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    padding: 30px;
    background: linear-gradient(to top, rgba(0,0,0,0.9), transparent);
}

.access-overlay h4 {
    color: #fff;
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 8px;
}

.access-overlay p {
    color: #aaa;
    font-size: 13px;
}

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

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

/* ========================================
   资讯列表板块
   ======================================== */
.news-section {
    background: #f8f8f8;
}

.news-category-title {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 30px;
    padding-left: 20px;
    border-left: 4px solid #000;
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-bottom: 60px;
}

.news-card {
    background: #fff;
    overflow: hidden;
    transition: all 0.4s ease;
}

.news-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.1);
}

.news-card img {
    width: 100%;
    height: 220px;
    object-fit: cover;
}

.news-card-content {
    padding: 25px;
}

.news-card-date {
    font-size: 13px;
    color: #999;
    margin-bottom: 10px;
}

.news-card-title {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 12px;
    color: #000;
    line-height: 1.5;
}

.news-card-excerpt {
    font-size: 14px;
    color: #666;
    line-height: 1.7;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

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

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

/* ========================================
   页脚
   ======================================== */
.footer {
    background: #000;
    color: #fff;
    padding: 80px 40px 40px;
}

.footer-container {
    max-width: 1400px;
    margin: 0 auto;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 60px;
    margin-bottom: 60px;
}

.footer-brand h3 {
    font-size: 24px;
    margin-bottom: 20px;
    letter-spacing: 2px;
}

.footer-brand p {
    font-size: 14px;
    color: #999;
    line-height: 1.8;
    margin-bottom: 25px;
}

.footer-contact p {
    font-size: 14px;
    color: #999;
    margin-bottom: 10px;
}

.footer-links h4,
.footer-nav h4 {
    font-size: 16px;
    margin-bottom: 25px;
    letter-spacing: 1px;
}

.footer-links ul li,
.footer-nav ul li {
    margin-bottom: 12px;
}

.footer-links ul li a,
.footer-nav ul li a {
    font-size: 14px;
    color: #999;
    transition: color 0.3s ease;
}

.footer-links ul li a:hover,
.footer-nav ul li a:hover {
    color: #fff;
}

.footer-bottom {
    border-top: 1px solid #333;
    padding-top: 30px;
    text-align: center;
}

.footer-bottom p {
    font-size: 13px;
    color: #666;
}

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

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

/* ========================================
   内页通用样式
   ======================================== */
.page-header {
    background: #000;
    padding: 180px 40px 100px;
    text-align: center;
}

.page-title {
    font-size: 48px;
    font-weight: 700;
    color: #fff;
    margin-bottom: 20px;
    letter-spacing: 2px;
}

.page-breadcrumb {
    font-size: 14px;
    color: #999;
}

.page-breadcrumb a {
    color: #999;
    transition: color 0.3s ease;
}

.page-breadcrumb a:hover {
    color: #fff;
}

.page-breadcrumb span {
    margin: 0 10px;
}

/* 内容区块 */
.content-block {
    padding: 100px 40px;
    max-width: 1400px;
    margin: 0 auto;
}

.content-block h2 {
    font-size: 36px;
    margin-bottom: 30px;
}

.content-block p {
    font-size: 16px;
    color: #666;
    line-height: 2;
    margin-bottom: 20px;
}

/* 图片展示 */
.image-showcase {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
    margin: 60px 0;
}

.image-showcase img {
    width: 100%;
    height: 400px;
    object-fit: cover;
}

/* 团队网格 */
.team-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
}

.team-card {
    text-align: center;
}

.team-card img {
    width: 100%;
    height: 350px;
    object-fit: cover;
    margin-bottom: 20px;
    filter: grayscale(100%);
    transition: filter 0.4s ease;
}

.team-card:hover img {
    filter: grayscale(0%);
}

.team-card h4 {
    font-size: 18px;
    margin-bottom: 8px;
}

.team-card p {
    font-size: 14px;
    color: #666;
}

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

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

/* 案例展示 */
.case-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.case-card {
    position: relative;
    overflow: hidden;
}

.case-card img {
    width: 100%;
    height: 300px;
    object-fit: cover;
    transition: transform 0.6s ease;
}

.case-card:hover img {
    transform: scale(1.1);
}

.case-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    padding: 30px;
    background: linear-gradient(to top, rgba(0,0,0,0.9), transparent);
}

.case-overlay h4 {
    color: #fff;
    font-size: 18px;
    margin-bottom: 8px;
}

.case-overlay p {
    color: #aaa;
    font-size: 13px;
}

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

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

/* 服务列表 */
.service-list {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.service-item {
    display: flex;
    align-items: flex-start;
    gap: 25px;
    padding: 40px;
    background: #f8f8f8;
    transition: all 0.4s ease;
}

.service-item:hover {
    background: #000;
    color: #fff;
}

.service-item:hover .service-title,
.service-item:hover .service-desc {
    color: #fff;
}

.service-number {
    font-size: 48px;
    font-weight: 800;
    color: #000;
    min-width: 80px;
}

.service-item:hover .service-number {
    color: #fff;
}

.service-content h3 {
    font-size: 22px;
    margin-bottom: 15px;
}

.service-title {
    font-size: 22px;
    font-weight: 600;
    margin-bottom: 15px;
    color: #000;
}

.service-desc {
    font-size: 15px;
    color: #666;
    line-height: 1.8;
}

@media (max-width: 768px) {
    .service-item {
        flex-direction: column;
        gap: 15px;
    }
}

/* 联系表单 */
.contact-form {
    max-width: 700px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 25px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 10px;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 18px 25px;
    border: 2px solid #ddd;
    font-size: 15px;
    font-family: inherit;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: #000;
}

.form-group textarea {
    min-height: 180px;
    resize: vertical;
}

.submit-btn {
    display: inline-block;
    padding: 20px 60px;
    background: #000;
    color: #fff;
    font-size: 16px;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: all 0.4s ease;
}

.submit-btn:hover {
    background: #333;
    transform: translateY(-3px);
}

/* 报价表格 */
.price-table {
    width: 100%;
    border-collapse: collapse;
    margin: 40px 0;
}

.price-table th,
.price-table td {
    padding: 25px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

.price-table th {
    background: #000;
    color: #fff;
    font-weight: 600;
    font-size: 16px;
}

.price-table tr:hover {
    background: #f8f8f8;
}

/* 滚动动画类 */
.fade-in {
    opacity: 0;
    transform: translateY(50px);
    transition: all 0.8s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* 新闻列表页 */
.news-list-page {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

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

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

/* 新闻详情页 */
.news-detail-content {
    max-width: 900px;
    margin: 0 auto;
}

.news-detail-header {
    margin-bottom: 40px;
}

.news-detail-title {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 20px;
    line-height: 1.4;
}

.news-detail-meta {
    font-size: 14px;
    color: #999;
}

.news-detail-body {
    font-size: 16px;
    line-height: 2;
    color: #333;
}

.news-detail-body img {
    width: 100%;
    margin: 30px 0;
}

.news-detail-body p {
    margin-bottom: 20px;
}

/* 相关新闻区域 */
.related-news-section {
    margin-top: 80px;
    padding-top: 60px;
    border-top: 1px solid #ddd;
}

.related-news-section h3 {
    font-size: 24px;
    margin-bottom: 30px;
}

/* 侧边栏新闻分类 */
.sidebar-news-categories {
    margin-bottom: 40px;
}

.sidebar-news-categories h4 {
    font-size: 18px;
    margin-bottom: 20px;
    padding-left: 15px;
    border-left: 3px solid #000;
}