/* 基础样式设置 */
:root {
    --primary-color: #2b5797;
    --secondary-color: #4CAF50;
    --text-color: #333;
}

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

body {
    font-family: 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

/* 导航栏样式 */
.main-nav {
    background: white;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
}

.main-nav .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 2px;
}

.logo-img {
    flex-shrink: 0;
}

.logo img {
    height: 50px;
    width: auto;
    transition: transform 0.3s ease;
    display: block;
}

.logo:hover img {
    transform: scale(1.05);
}

.logo-text {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.logo-text h1 {
    font-size: 1.4rem;
    color: var(--primary-color);
    font-weight: 600;
    line-height: 1.2;
    margin: 0;
}

.logo-text p {
    font-size: 0.85rem;
    color: #666;
    margin: 0;
}

/* 汉堡菜单按钮样式 */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 20px;
    cursor: pointer;
    z-index: 1001;
}

.menu-toggle span {
    display: block;
    height: 3px;
    width: 100%;
    background-color: var(--primary-color);
    transition: all 0.3s ease;
}

.menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

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

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

/* 导航菜单样式 */
.nav-menu {
    flex: 1;
    margin: 0 40px;
}

.menu-list {
    display: flex;
    list-style: none;
    justify-content: center;
}

.menu-list > li {
    position: relative;
    margin: 0 20px;
}

.menu-list > li > a {
    color: var(--text-color);
    text-decoration: none;
    font-size: 16px;
    padding: 30px 0;
    display: block;
    transition: color 0.3s ease;
}

.menu-list > li > a:hover,
.menu-list > li > a.active {
    color: var(--primary-color);
}

/* 下拉菜单样式 */
.dropdown {
    position: relative;
}

.submenu {
    position: absolute;
    top: 100%;
    left: 0;
    background: white;
    min-width: 200px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all 0.3s ease;
    list-style: none;
    border-radius: 4px;
}

.dropdown:hover .submenu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.submenu li a {
    color: var(--text-color);
    text-decoration: none;
    padding: 12px 20px;
    display: block;
    font-size: 14px;
    transition: background 0.3s ease;
}

.submenu li a:hover {
    background: #f5f5f5;
    color: var(--primary-color);
}

/* 页脚样式 */
.footer {
    background: #2b2b2b;
    color: #fff;
    padding: 60px 0 20px;
    margin-top: 60px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h4 {
    color: #fff;
    font-size: 1.2rem;
    margin-bottom: 20px;
    position: relative;
}

.footer-section h4::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -8px;
    width: 40px;
    height: 2px;
    background: var(--primary-color);
}

.footer-section p {
    color: #999;
    line-height: 1.6;
}

.footer-links {
    list-style: none;
    padding: 0;
}

.footer-links li {
    margin-bottom: 10px;
}

.footer-links a {
    color: #999;
    text-decoration: none;
    transition: color 0.3s ease;
}

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

.footer-contact {
    list-style: none;
    padding: 0;
}

.footer-contact li {
    color: #999;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
}

.footer-contact i {
    margin-right: 10px;
    color: var(--primary-color);
}

.footer-bottom {
    border-top: 1px solid #3a3a3a;
    padding-top: 20px;
    text-align: center;
}

.copyright {
    color: #999;
    margin-bottom: 10px;
}

.icp {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.icp a {
    color: #999;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 5px;
}

.icp img {
    height: 16px;
}

/* 响应式样式 */
@media screen and (max-width: 992px) {
    .logo-text h1 {
        font-size: 1.2rem;
    }
    
    .logo-text p {
        font-size: 0.75rem;
    }
}

@media screen and (max-width: 768px) {
    .main-nav .container {
        height: 60px;
    }

    .logo {
        gap: 2px;
    }

    .logo img {
        height: 40px;
    }

    .logo-text {
        gap: 2px;
    }

    .logo-text h1 {
        font-size: 1rem;
    }
    
    .logo-text p {
        font-size: 0.7rem;
        line-height: 1.2;
        display: block;
    }

    .menu-toggle {
        display: flex;
    }

    .nav-menu {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: rgba(0, 0, 0, 0.9);
        margin: 0;
        padding: 80px 20px 20px;
        z-index: 1000;
        overflow-y: auto;
    }

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

    .menu-list {
        flex-direction: column;
        align-items: center;
    }

    .menu-list > li {
        margin: 10px 0;
        width: 100%;
        text-align: center;
    }

    .menu-list > li > a {
        padding: 15px 0;
        color: white;
        font-size: 18px;
    }

    .menu-list > li > a:hover,
    .menu-list > li > a.active {
        color: var(--secondary-color);
    }

    .submenu {
        position: static;
        background: transparent;
        box-shadow: none;
        opacity: 1;
        visibility: visible;
        transform: none;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s ease;
    }

    .dropdown.active .submenu {
        max-height: 500px;
    }

    .submenu li a {
        color: #ccc;
        padding: 10px 0;
        font-size: 16px;
        text-align: center;
    }

    .submenu li a:hover {
        background: transparent;
        color: var(--secondary-color);
    }

    .footer-content {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media screen and (max-width: 480px) {
    .logo img {
        height: 35px;
    }

    .logo {
        gap: 2px;
    }

    .logo-text h1 {
        font-size: 0.9rem;
    }
    
    .logo-text p {
        font-size: 0.65rem;
    }

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