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

:root {
    --deep-blue: #003366;
    --light-blue: #4A90E2;
    --yellow: #FFD700;
    --black: #000000;
    --white: #FFFFFF;
    --gray: #F5F5F5;
}

body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    color: var(--black);
}

html {
    scroll-behavior: smooth;
}

/* Header Styles */
.main-header {
    background-color: var(--white);
    padding: 20px 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.header-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
}

.nav-row {
    display: flex;
    align-items: center;
    gap: 40px;
    margin-bottom: 15px;
}

.logo img {
    height: 60px;
    width: auto;
    background-color: var(--gray);
    padding: 10px;
}

.main-nav {
    display: flex;
    gap: 30px;
    flex: 1;
}

.nav-link {
    text-decoration: none;
    color: var(--black);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 5px;
    transition: all 0.3s ease;
    padding: 5px 10px;
    position: relative;
}

.nav-line {
    height: 3px;
    width: 100%;
    background-color: var(--deep-blue);
    transition: all 0.3s ease;
}

.nav-link.active .nav-line {
    height: 5px;
    font-weight: bold;
}

.nav-link:hover .nav-text,
.nav-link.active .nav-text {
    color: var(--light-blue);
}

.nav-text {
    font-size: 16px;
    transition: color 0.3s ease;
}

/* Dropdown Menu Styles */
.nav-link.has-dropdown {
    position: relative;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--white);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.15);
    border-radius: 5px;
    padding: 10px 0;
    min-width: 200px;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    margin-top: 10px;
    z-index: 1001;
}

.nav-link.has-dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    margin-top: 5px;
}

.dropdown-item {
    display: block;
    padding: 12px 20px;
    color: var(--black);
    text-decoration: none;
    transition: all 0.3s ease;
    font-size: 15px;
}

.dropdown-item:hover {
    background-color: var(--light-blue);
    color: var(--white);
}

.dropdown-item.active {
    background-color: var(--deep-blue);
    color: var(--white);
}

/* Action Row */
.action-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.action-spacer {
    flex: 1;
}

.action-buttons {
    display: flex;
    gap: 20px;
    margin-right: 40px;
}

.action-btn {
    background-color: var(--yellow);
    color: var(--white);
    padding: 10px 20px;
    border-radius: 5px;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: bold;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
}

.action-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.action-btn i {
    font-size: 14px;
}

/* Header Separator */
.header-separator {
    height: 4px;
    width: 80%;
    background-color: var(--deep-blue);
    margin: 0 auto;
}

/* Main Content */
.main-content {
    max-width: 1400px;
    margin: 0 auto;
}

/* Carousel Section */
.carousel-section {
    margin: 40px 0;
}

.carousel {
    position: relative;
    width: 100%;
    height: 500px;
    overflow: hidden;
    background-color: var(--gray);
}

.carousel-track {
    width: 100%;
    height: 100%;
    position: relative;
}

.carousel-slide {
    position: absolute;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 0.5s ease-in-out;
}

.carousel-slide.active {
    opacity: 1;
}

.carousel-slide img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.carousel-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background-color: rgba(0, 0, 0, 0.5);
    color: var(--white);
    border: none;
    padding: 15px 20px;
    cursor: pointer;
    font-size: 20px;
    transition: background-color 0.3s ease;
    z-index: 10;
}

.carousel-btn:hover {
    background-color: rgba(0, 0, 0, 0.8);
}

.carousel-btn.prev {
    left: 20px;
}

.carousel-btn.next {
    right: 20px;
}

.carousel-indicators {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 10px;
    z-index: 10;
}

.indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background-color: rgba(255, 255, 255, 0.5);
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.indicator.active {
    background-color: var(--white);
}

/* Content Sections */
.content-sections {
    padding: 40px 20px;
}

.content-row {
    display: flex;
    align-items: center;
    gap: 60px;
    margin-bottom: 60px;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
}

.content-row.reverse {
    flex-direction: row-reverse;
}

.content-text {
    flex: 1;
}

.content-text h2 {
    font-size: 32px;
    color: var(--deep-blue);
    margin-bottom: 20px;
}

.content-text p {
    font-size: 16px;
    line-height: 1.8;
    color: #333;
}

.content-image {
    flex: 1;
}

.content-image img {
    width: 100%;
    height: 300px;
    object-fit: cover;
    border-radius: 8px;
    background-color: var(--gray);
}

/* Section Separator */
.section-separator {
    height: 4px;
    width: 80%;
    background-color: var(--deep-blue);
    margin: 60px auto;
}

/* Industries Section */
.industries-section {
    padding: 40px 20px;
    text-align: center;
}

.section-title {
    font-size: 36px;
    color: var(--light-blue);
    margin-bottom: 40px;
}

.industries-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
    max-width: 1000px;
    margin: 0 auto;
}

.industry-item {
    text-decoration: none;
    color: var(--black);
    transition: transform 0.3s ease;
}

.industry-item:hover {
    transform: translateY(-10px);
}

.industry-image {
    width: 100%;
    height: 300px;
    overflow: hidden;
    border-radius: 8px;
    margin-bottom: 15px;
}

.industry-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    background-color: var(--gray);
}

.industry-name {
    font-size: 20px;
    font-weight: bold;
    color: var(--deep-blue);
}

/* Partners Section */
.partners-section {
    padding: 40px 20px 80px;
    text-align: center;
}

.partners-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 30px;
    max-width: 1200px;
    margin: 0 auto;
    align-items: center;
}

.partner-item {
    padding: 20px;
    background-color: var(--white);
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    transition: box-shadow 0.3s ease;
}

.partner-item:hover {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.partner-item img {
    width: 100%;
    height: 80px;
    object-fit: contain;
    background-color: var(--gray);
}

/* Footer Styles */
.main-footer {
    background-color: var(--deep-blue);
    color: var(--white);
    padding: 40px 20px;
    margin-top: 60px;
}

.footer-content {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
}

.footer-logo img {
    height: 60px;
    width: auto;
    background-color: var(--white);
    padding: 10px;
    border-radius: 5px;
}

.footer-copyright {
    text-align: center;
}

.footer-copyright p {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.8);
}

.footer-actions {
    display: flex;
    gap: 15px;
}

.footer-btn {
    width: 40px;
    height: 40px;
    background-color: var(--light-blue);
    color: var(--white);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    text-decoration: none;
    transition: all 0.3s ease;
}

.footer-btn:hover {
    background-color: var(--yellow);
    transform: translateY(-3px);
}

.footer-btn i {
    font-size: 18px;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .nav-row {
        flex-direction: column;
        gap: 20px;
    }
    
    .main-nav {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .content-row,
    .content-row.reverse {
        flex-direction: column;
    }
    
    .industries-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .main-nav {
        gap: 15px;
    }
    
    .nav-link {
        font-size: 14px;
    }
    
    .carousel {
        height: 300px;
    }
    
    .content-text h2 {
        font-size: 24px;
    }
    
    .section-title {
        font-size: 28px;
    }
    
    .action-buttons {
        margin-right: 0;
    }
}
/* ========== 新增：多级下拉菜单样式 ========== */

/* 1. 基础下拉菜单调整 */
.dropdown-menu {
    /* 保持原有样式，增加对齐修正 */
    text-align: left;
    padding: 0; /* 移除默认内边距，由item控制 */
    background-color: var(--white);
    border-radius: 0 0 5px 5px;
}

/* 2. 下拉菜单项样式调整 */
.dropdown-item {
    position: relative; /* 为子菜单定位做基准 */
    display: flex;
    justify-content: space-between; /* 让文字和箭头分列两边 */
    align-items: center;
    padding: 15px 20px; /* 增加点击区域 */
    border-bottom: 1px solid #f0f0f0;
    white-space: nowrap; /* 防止文字换行 */
}

.dropdown-item:last-child {
    border-bottom: none;
}

/* 3. 子菜单 (Level 2 & Level 3) 通用样式 */
.submenu {
    display: none; /* 默认隐藏 */
    position: absolute;
    left: 100%; /* 显示在父级右侧 */
    top: 0;
    background-color: var(--white);
    box-shadow: 2px 2px 15px rgba(0, 0, 0, 0.15);
    min-width: 280px; /* 宽度自适应，防止过窄 */
    border-radius: 0 5px 5px 5px;
    z-index: 1002;
}

/* 4. 悬停显示逻辑 */
/* 当鼠标悬停在拥有 .has-submenu 的 .dropdown-item 上时，显示其直属的 .submenu */
.dropdown-item.has-submenu:hover > .submenu {
    display: block;
}

/* 5. 箭头图标样式 */
.dropdown-item i.fa-chevron-right {
    font-size: 12px;
    color: #999;
    margin-left: 10px;
}

.dropdown-item:hover i.fa-chevron-right {
    color: var(--white); /* 悬停时变白 */
}


/* 6. 针对 Application Industries 标题链接的特殊处理 */
/* 让标题既保持原有nav-text样式，又是可点击链接 */
a.nav-text {
    text-decoration: none;
    color: inherit; /* 继承父级颜色 */
    cursor: pointer;
    display: block; /* 撑满区域 */
}

/* 7. 修正下拉菜单宽度，适应长文本 */
.dropdown-menu {
    min-width: 260px;
}
/* 针对特定的长文本菜单增加宽度 */
.submenu {
    min-width: 320px; 
}