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

body {
    font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
    padding-bottom: 60px;
    background: #f5f7fa;
    color: #333;
}

#header {
    width: 100%;
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
    padding: 15px 0;
}

.header-content {
    text-align: center;
}

.company-name {
    font-size: 24px;
    font-weight: 900;
    color: white;
    text-shadow: 3px 3px 6px rgba(0,0,0,0.3);
    margin-bottom: 5px;
    letter-spacing: 2px;
}

.company-phone {
    font-size: 15px;
    color: #f0f0f0;
    font-weight: 600;
    letter-spacing: 1px;
}

#mainNav {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1px;
    background: #ddd;
    border-top: 1px solid #ddd;
    border-bottom: 1px solid #ddd;
}

.nav-item {
    background: white;
    padding: 18px 10px;
    text-align: center;
    cursor: pointer;
    font-size: 17px;
    font-weight: 600;
    color: #333;
    transition: all 0.3s;
    font-family: "Microsoft YaHei", "PingFang SC", sans-serif;
}

.nav-item:hover {
    background: #1890ff;
    color: white;
}

.nav-item:active {
    background: #096dd9;
    transform: scale(0.98);
}

#mainContent {
    min-height: calc(100vh - 200px);
    padding: 20px 15px;
    background: #f5f7fa;
}

.page-title {
    text-align: center;
    font-size: 30px;
    margin: 30px 0 10px;
    color: #1e3c72;
    font-weight: bold;
    position: relative;
    padding: 0 20px;
}

.page-title::before,
.page-title::after {
    content: '';
    position: absolute;
    top: 50%;
    width: 80px;
    height: 4px;
    background: linear-gradient(90deg, #1e3c72, #2a5298);
    border-radius: 2px;
}

.page-title::before {
    left: 8%;
    transform: translateY(-50%);
}

.page-title::after {
    right: 8%;
    transform: translateY(-50%);
}

.page-subtitle {
    text-align: center;
    font-size: 13px;
    color: #999;
    margin-bottom: 25px;
    letter-spacing: 3px;
    font-weight: 300;
}

.about-content {
    background: #ffffff;
    padding: 30px 25px;
    border-radius: 12px;
    line-height: 2.2;
    color: #333;
    box-shadow: 0 4px 16px rgba(30, 60, 114, 0.12);
    margin: 20px auto;
    border: 2px solid #2a5298;
    font-size: 15px;
    max-width: 90%;
}

.about-content p {
    margin-bottom: 18px;
    text-indent: 2em;
    text-align: center;
}

.product-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin: 20px 0;
    justify-content: center;
    background: #f8f9fa;
    padding: 12px;
    border-radius: 10px;
}

.tab-item {
    padding: 8px 14px;
    background: white;
    border-radius: 20px;
    cursor: pointer;
    font-size: 13px;
    transition: all 0.3s;
    border: 2px solid #e0e0e0;
    font-weight: 600;
    color: #555;
}

.tab-item.active {
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
    color: white;
    border-color: #1e3c72;
    box-shadow: 0 3px 10px rgba(30, 60, 114, 0.3);
}

.tab-item:active {
    transform: scale(0.95);
}

.banner-slider {
    width: 100vw;
    margin-left: -15px;
    overflow: hidden;
    position: relative;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.banner-slider img {
    width: 100%;
    display: block;
    transition: transform 0.6s ease-in-out;
}

.home-section {
    margin: 20px -10px;
    padding: 25px 15px;
    background: white;
    border-radius: 12px;
    box-shadow: 0 2px 12px rgba(30, 60, 114, 0.08);
}

.home-section:first-of-type {
    margin-top: 20px;
}

.section-title {
    font-size: 24px;
    font-weight: bold;
    text-align: center;
    margin-bottom: 20px;
    margin-top: 15px;
    color: #1e3c72;
    position: relative;
    padding: 0 20px;
}

.section-title::before,
.section-title::after {
    content: '';
    position: absolute;
    top: 50%;
    width: 50px;
    height: 3px;
    background: linear-gradient(90deg, #1e3c72, #2a5298);
    border-radius: 2px;
}

.section-title::before {
    left: 10%;
    transform: translateY(-50%);
}

.section-title::after {
    right: 10%;
    transform: translateY(-50%);
}

.section-title .en-title {
    display: block;
    font-size: 12px;
    color: #999;
    font-weight: normal;
    margin-top: 5px;
    letter-spacing: 2px;
}

.about-preview {
    line-height: 1.8;
    color: #666;
    text-indent: 2em;
}

.btn-more {
    padding: 8px 30px;
    background: #1890ff;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

.btn-more:active {
    background: #096dd9;
}

.product-grid, .case-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 15px;
    margin: 20px 0;
}

.product-item, .case-item {
    text-align: center;
    cursor: pointer;
}

.product-item img, .case-item img {
    width: 100%;
    height: 150px;
    object-fit: cover;
    border-radius: 8px;
}

.product-item p, .case-item p {
    margin-top: 8px;
    font-size: 14px;
}

.breadcrumb {
    font-size: 12px;
    color: #666;
    margin-bottom: 15px;
}

.breadcrumb span {
    cursor: pointer;
    color: #1890ff;
}

.news-list, .knowledge-list {
    list-style: none;
    background: white;
    border-radius: 10px;
    overflow: hidden;
}

.news-item, .knowledge-item {
    padding: 18px;
    border-bottom: 1px solid #f0f0f0;
    cursor: pointer;
    transition: all 0.3s;
}

.news-item:last-child, .knowledge-item:last-child {
    border-bottom: none;
}

.news-item:active, .knowledge-item:active {
    background: #f8f9fa;
    padding-left: 22px;
}

.news-title {
    font-size: 15px;
    margin-bottom: 8px;
    color: #333;
    font-weight: 600;
}

.news-date {
    font-size: 12px;
    color: #2a5298;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-size: 14px;
    font-weight: 600;
    color: #333;
}

.form-group input, .form-group textarea {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 14px;
    transition: all 0.3s;
    font-family: inherit;
}

.form-group input:focus, .form-group textarea:focus {
    outline: none;
    border-color: #2a5298;
    box-shadow: 0 0 0 3px rgba(42, 82, 152, 0.1);
}

.form-group textarea {
    height: 120px;
    resize: vertical;
}

.btn-submit {
    width: 100%;
    padding: 14px;
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: 0 4px 12px rgba(30, 60, 114, 0.3);
}

.btn-submit:active {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(30, 60, 114, 0.4);
}

.contact-info {
    line-height: 2.2;
    font-size: 15px;
    background: white;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 2px 12px rgba(30, 60, 114, 0.08);
}

.contact-info p {
    margin-bottom: 15px;
    color: #333;
}

.contact-info strong {
    color: #1e3c72;
    font-weight: 600;
}

#bottomNav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    display: flex;
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
    border-top: none;
    z-index: 1000;
    box-shadow: 0 -2px 10px rgba(0,0,0,0.1);
}

.bottom-item {
    flex: 1;
    text-align: center;
    padding: 10px 0;
    cursor: pointer;
    transition: all 0.3s;
    border-right: 1px solid rgba(255,255,255,0.3);
}

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

.bottom-item:active {
    background: rgba(255,255,255,0.15);
}

.bottom-item span {
    font-size: 24px;
    display: block;
}

.bottom-item p {
    font-size: 12px;
    margin-top: 4px;
    color: white;
    font-weight: 500;
}

/* 产品优势样式 */
.advantages-container {
    max-width: 95%;
    margin: 30px auto;
}

.advantage-item {
    display: flex;
    align-items: center;
    margin-bottom: 30px;
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
    border-radius: 15px;
    padding: 20px;
    box-shadow: 0 8px 20px rgba(30, 60, 114, 0.4);
}

.advantage-item.right {
    background: linear-gradient(135deg, #2a5298 0%, #1e3c72 100%);
    box-shadow: 0 8px 20px rgba(42, 82, 152, 0.4);
    flex-direction: row-reverse;
}

.advantage-item img {
    width: 45%;
    height: 180px;
    object-fit: cover;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.advantage-text {
    flex: 1;
    padding: 0 25px;
    color: white;
}

.advantage-text h3 {
    font-size: 24px;
    margin-bottom: 12px;
    font-weight: bold;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.advantage-text p {
    font-size: 15px;
    line-height: 1.8;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.2);
}

.advantages-preview {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 15px;
}

.advantage-preview-item {
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
    border-radius: 12px;
    padding: 15px;
    text-align: center;
    cursor: pointer;
    box-shadow: 0 4px 12px rgba(30, 60, 114, 0.25);
    transition: all 0.3s;
}

.advantage-preview-item:active {
    transform: translateY(-5px);
    box-shadow: 0 6px 20px rgba(30, 60, 114, 0.35);
}

.advantage-preview-item img {
    width: 100%;
    height: 120px;
    object-fit: cover;
    border-radius: 8px;
    margin-bottom: 10px;
}

.advantage-preview-item h4 {
    color: white;
    font-size: 17px;
    margin-bottom: 8px;
    font-weight: bold;
}

.advantage-preview-item p {
    color: #e8f0fe;
    font-size: 13px;
    line-height: 1.6;
}

/* 图片预览弹窗 */
.image-preview-modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.9);
    z-index: 9999;
    justify-content: center;
    align-items: center;
    flex-direction: column;
}

.image-preview-modal.active {
    display: flex;
}

.image-preview-modal img {
    max-width: 90%;
    max-height: 70vh;
    object-fit: contain;
    border-radius: 8px;
}

.image-preview-title {
    color: white;
    font-size: 18px;
    margin-top: 20px;
    text-align: center;
}

.image-preview-close {
    position: absolute;
    top: 20px;
    right: 20px;
    color: white;
    font-size: 36px;
    cursor: pointer;
    width: 40px;
    height: 40px;
    line-height: 40px;
    text-align: center;
}