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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    overflow-x: hidden;
}

/* 页面加载过渡与遮罩 */
body.page-loading {
    overflow: hidden;
}

body.page-loaded {
    overflow-x: hidden;
}

.page-loading-overlay {
    position: fixed;
    inset: 0;
    background: radial-gradient(circle at 10% 0%, rgba(44, 82, 130, 0.45), transparent 60%),
                radial-gradient(circle at 90% 10%, rgba(229, 62, 62, 0.35), transparent 55%),
                #0b1220;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    opacity: 1;
    visibility: visible;
    transition: opacity 0.4s ease, visibility 0.4s ease;
}

body.page-loaded .page-loading-overlay {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.page-loading-inner {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}

.page-loading-spinner {
    width: 46px;
    height: 46px;
    border-radius: 50%;
    border: 3px solid rgba(226, 232, 240, 0.22);
    border-top-color: #f6ad55;
    animation: page-loading-spin 0.8s linear infinite;
}

.page-loading-text {
    color: rgba(226, 232, 240, 0.9);
    font-size: 14px;
    letter-spacing: 2px;
    text-transform: uppercase;
}

@keyframes page-loading-spin {
    to {
        transform: rotate(360deg);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

/* 导航栏 */
.navbar .container {
    max-width: 100%;
    padding: 0 20px;
}

.navbar {
    background: rgba(26, 32, 44, 0.85);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 18px 0;
    backdrop-filter: blur(5px);
}

.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    gap: 20px;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1.1;
    flex-shrink: 0;
    padding: 4px 10px;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.92);
}

.logo-image {
    display: block;
    height: 52px;
    width: auto;
}

.logo-main {
    font-size: 32px;
    font-weight: 700;
    color: #fff;
    letter-spacing: 0.5px;
    line-height: 1;
}

.logo-sub {
    font-size: 13px;
    font-weight: 400;
    color: #fff;
    letter-spacing: 1.5px;
    margin-top: 2px;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 32px;
    align-items: center;
    margin: 0;
    padding: 0;
    flex: 1;
    justify-content: flex-end;
    margin-right: 25px;
}

.nav-menu li {
    margin: 0;
    padding: 0;
}

.nav-menu a {
    text-decoration: none;
    color: #fff;
    font-weight: 400;
    font-size: 15px;
    transition: color 0.3s;
    white-space: nowrap;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: #fff;
    font-weight: 500;
}

/* 语言选择器 */
.language-selector {
    margin-left: 20px;
    flex-shrink: 0;
}

.lang-select {
    background: rgba(255, 255, 255, 0.95);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 6px;
    color: #1a202c;
    font-size: 14px;
    font-weight: 400;
    padding: 8px 35px 8px 12px;
    cursor: pointer;
    transition: all 0.3s;
    font-family: inherit;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%231a202c' d='M6 9L1 4h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 12px;
}

.lang-select:hover {
    background-color: #fff;
    border-color: rgba(255, 255, 255, 0.5);
}

.lang-select:focus {
    outline: none;
    border-color: rgba(255, 255, 255, 0.7);
    box-shadow: 0 0 0 2px rgba(255, 255, 255, 0.2);
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 28px;
    cursor: pointer;
    color: #fff;
}

/* 主页横幅 */
.hero {
    /* 保持图片比例，避免变形 */
    background-color: #fff;
    background-image: url('images/IMG_5069-.jpg');
    background-repeat: no-repeat;
    background-position: center;
    /* 按当前裁剪比例展示（不改 background-size） */
    background-size: 100% 95%;
    color: white;
    padding: 200px 20px 150px;
    text-align: center;
    position: relative;
    overflow: hidden;
    min-height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><rect width="100" height="100" fill="%231a365d"/><path d="M0 50 L100 50" stroke="%232c5282" stroke-width="0.5" opacity="0.3"/></svg>');
    opacity: 0.3;
    z-index: 1;
}

/* 底部渐变过渡：在不改变裁剪的情况下，让图片自然融入下面白色内容区 */
.hero::after {
    content: '';
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    height: 18%;
    min-height: 80px;
    background: linear-gradient(to bottom,
                rgba(255, 255, 255, 0) 0%,
                rgba(255, 255, 255, 0.55) 55%,
                #ffffff 100%);
    z-index: 1;
    pointer-events: none;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: 1;
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 900px;
    margin: 0 auto;
}

.hero-subtitle {
    font-size: 16px;
    margin-bottom: 25px;
    opacity: 0.9;
    letter-spacing: 3px;
    text-transform: uppercase;
    font-weight: 500;
}

.hero-title {
    font-size: 64px;
    font-weight: 700;
    margin-bottom: 50px;
    line-height: 1.2;
}

.btn-primary {
    display: inline-block;
    padding: 15px 40px;
    background: #e53e3e;
    color: white;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    transition: background 0.3s;
    font-size: 15px;
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    background: #c53030;
}

/* Section 通用样式 */
section {
    padding: 100px 20px;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-label {
    font-size: 14px;
    color: #2c5282;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 15px;
    font-weight: 600;
}

.section-title {
    font-size: 42px;
    font-weight: 700;
    color: #1a202c;
    line-height: 1.3;
}

/* About 部分 */
.about {
    background: #fff;
    padding: 120px 20px;
}

.content-wrapper {
    display: grid;
    grid-template-columns: 0.85fr 1.15fr;
    gap: 80px;
    align-items: center;
}

.content-left {
    max-width: 100%;
    padding-right: 20px;
}

.content-left .section-label {
    font-size: 13px;
    color: #e53e3e;
    text-transform: uppercase;
    letter-spacing: 3px;
    margin-bottom: 20px;
    font-weight: 600;
    display: inline-block;
    padding-bottom: 8px;
    border-bottom: 2px solid #e53e3e;

}

.content-left .section-title {
    font-size: 38px;
    font-weight: 700;
    color: #1a202c;
    line-height: 1.3;
    margin-bottom: 30px;
}

.content-left p {
    font-size: 16px;
    line-height: 1.9;
    color: #4a5568;
    margin-bottom: 20px;
}

.content-right {
    max-width: 100%;
}

/* 首页 About 区右侧图片 */
.about-image-wrapper {
    position: relative;
    width: 100%;
    max-width: 900px;
    margin-left: auto;
}

.about-image {
    width: 100%;
    height: auto;
    border-radius: 24px;
    object-fit: contain;
    box-shadow: 0 30px 80px rgba(15, 23, 42, 0.2),
                0 10px 30px rgba(15, 23, 42, 0.1);
    border: 4px solid #fff;
    transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1), 
                box-shadow 0.4s ease;
    display: block;
}

.about-image-wrapper:hover .about-image {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 40px 100px rgba(15, 23, 42, 0.3),
                0 15px 40px rgba(15, 23, 42, 0.15);
}

.about-image-wrapper::after {
    content: '';
    position: absolute;
    top: 20px;
    right: 20px;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: linear-gradient(135deg, rgba(229, 62, 62, 0.15) 0%, rgba(44, 82, 130, 0.15) 100%);
    z-index: -1;
    opacity: 0;
    transition: opacity 0.4s ease, transform 0.4s ease;
}

.about-image-wrapper:hover::after {
    opacity: 1;
    transform: scale(1.2);
}

.content-heading {
    font-size: 32px;
    font-weight: 700;
    color: #1a202c;
    line-height: 1.3;
    margin-bottom: 25px;
}

.content-left p,
.content-right p {
    font-size: 16px;
    line-height: 1.8;
    margin-bottom: 20px;
    color: #4a5568;
}

/* Service 部分 */
.service {
    position: relative;
    /* 背景图片：居中且铺满区域 */
    background: url('images/t1.jpg') center center / cover no-repeat;
    overflow: hidden;
}

.service::before {
    content: "";
    position: absolute;
    inset: 0;
    /* 半透明的白色渐变遮罩，让背景图还能透出来 */
    background: linear-gradient(145deg, rgba(255, 255, 255, 0.7), rgba(237, 242, 247, 0.7));
    /* 如果你希望效果更柔和，可以保留，也可以去掉这一行 */
    mix-blend-mode: screen;
}

.service .container {
    position: relative;
    z-index: 1;
}

.service .section-header {
    margin-bottom: 50px;
}

.service .section-label {
    color: #e53e3e;
}

.service-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 36px;
    margin-bottom: 60px;
}

.service-item {
    padding: 38px 32px 42px;
    background: radial-gradient(circle at 0 0, rgba(226, 232, 240, 0.9), transparent 55%),
                radial-gradient(circle at 100% 100%, rgba(237, 242, 247, 0.9), transparent 55%),
                #ffffff;
    border-radius: 20px;
    border: 1px solid rgba(226, 232, 240, 0.9);
    box-shadow: 0 18px 40px rgba(15, 23, 42, 0.16);
    transition: transform 0.35s ease, box-shadow 0.35s ease, border-color 0.35s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.service-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 24px 55px rgba(15, 23, 42, 0.24);
    border-color: rgba(229, 62, 62, 0.45);
}

.service-item h3 {
    font-size: 20px;
    letter-spacing: 1.5px;
    text-transform: uppercase;
    color: #1a202c;
    margin-bottom: 18px;
    font-weight: 700;
}

.service-item img {
    width: 100%;
    max-width: 220px;
    height: 260px;
    object-fit: contain;
    /* 去掉图片阴影 */
    filter: none;
    transition: transform 0.4s ease;
}

.service-item:hover img {
    transform: translateY(-6px) scale(1.03);
    /* 悬停时同样不添加阴影 */
    filter: none;
}

.service-item p {
    color: #718096;
    line-height: 1.7;
    font-size: 15px;
}

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

.service-tagline {
    font-size: 20px;
    color: #1a202c;
    margin-bottom: 30px;
    font-weight: 500;
}

/* Projects 部分 */
.projects {
    background: #fff;
}

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

.project-item {
    padding: 40px;
    background: #f7fafc;
    border-radius: 8px;
    transition: transform 0.3s;
}

.project-item:hover {
    transform: translateY(-5px);
}

.project-item h3 {
    font-size: 22px;
    color: #1a202c;
    margin-bottom: 15px;
    font-weight: 600;
}

.project-item p {
    color: #718096;
    line-height: 1.7;
    font-size: 15px;
}

/* Certification 图片样式 */
.certification-item {
    padding: 0;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.certification-item a {
    display: block;
    width: 100%;
}

.certification-item .certification-image {
    width: 100%;
    height: auto;
    display: block;
    object-fit: contain;
    transition: transform 0.3s ease;
}

.certification-item:hover .certification-image {
    transform: scale(1.05);
}

/* Projects 页面（projects.html） */
.projects-page {
    background: #fff;
}

.projects-page-header {
    max-width: 720px;
    margin: 0 auto 60px;
    text-align: center;
}

.projects-intro {
    margin-top: 18px;
    font-size: 16px;
    line-height: 1.8;
    color: #4a5568;
}

.projects-page-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 28px;
}

.project-card {
    background: #f7fafc;
    border-radius: 18px;
    overflow: hidden;
    box-shadow: 0 18px 45px rgba(15, 23, 42, 0.12);
    display: flex;
    flex-direction: column;
}

.project-card-media {
    height: 220px;
    background-size: cover;
    background-position: center;
}

.project-card--aerospace .project-card-media {
    background-image: url('https://images.pexels.com/photos/3140201/pexels-photo-3140201.jpeg?auto=compress&cs=tinysrgb&w=900&h=600&fit=crop');
}

.project-card--oil .project-card-media {
    background-image: url('https://images.pexels.com/photos/9793811/pexels-photo-9793811.jpeg?auto=compress&cs=tinysrgb&w=900&h=600&fit=crop');
}

.project-card--automotive .project-card-media {
    background-image: url('https://images.pexels.com/photos/4489734/pexels-photo-4489734.jpeg?auto=compress&cs=tinysrgb&w=900&h=600&fit=crop');
}

.project-card-body {
    padding: 26px 26px 28px;
}

.project-card-title {
    font-size: 20px;
    font-weight: 600;
    color: #1a202c;
    margin-bottom: 12px;
}

.project-card-text {
    font-size: 15px;
    line-height: 1.8;
    color: #4a5568;
}

/* CTA 部分 */
.cta {
    background: url('images/65446.jpg') center/cover no-repeat;
    color: white;
    text-align: center;
    padding: 120px 20px;
    position: relative;
    overflow: hidden;
    min-height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.cta::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1;
}

.cta .container {
    position: relative;
    z-index: 2;
}

.cta h2 {
    font-size: 42px;
    margin-bottom: 25px;
    font-weight: 700;
    line-height: 1.3;
}

.cta p {
    font-size: 18px;
    margin-bottom: 40px;
    opacity: 0.9;
}

/* Footer - 重新设计整体布局 */
.footer {
    background: #0b1220;
    color: #e2e8f0;
    padding: 100px 20px 40px;
}

.footer .container {
    max-width: 1300px;
}

.footer-content {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    /* 增大列与列之间的间距 */
    gap: 60px;
    margin-bottom: 50px;
}

.footer-brand,
.footer-column,
.footer-contact-column,
.footer-mail-column {
    display: flex;
    flex-direction: column;
    min-width: 0;
}

/* 左侧标题/介绍列最宽，其余三列固定宽度，保证列间距看起来均匀 */
.footer-brand {
    flex: 0 0 32%;
    padding-right: 20px;
}

.footer-column {
    /* 缩小 COMPANY 所在列的宽度，让两侧内容更宽 */
    flex: 0 0 10%;
}

.footer-contact-column,
.footer-mail-column {
    flex: 0 0 24%;
}

.footer-logo {
    font-size: 24px;
    font-weight: 700;
    color: #fff;
    letter-spacing: 0.3px;
    margin-bottom: 16px;
}

.footer-tagline {
    font-size: 14px;
    font-weight: 600;
    color: rgba(226, 232, 240, 0.9);
    letter-spacing: 0.8px;
    margin-bottom: 18px;
}

.footer-desc {
    font-size: 15px;
    line-height: 1.9;
    color: rgba(226, 232, 240, 0.75);
}

.footer-column h4,
.footer-contact-title {
    font-size: 13px;
    margin-bottom: 24px;
    color: rgba(226, 232, 240, 0.9);
    font-weight: 700;
    letter-spacing: 2.5px;
    text-transform: uppercase;
}

.footer-column ul {
    list-style: none;
}

.footer-column ul li {
    margin-bottom: 14px;
    color: rgba(226, 232, 240, 0.78);
    font-size: 15px;
    line-height: 1.7;
}

.footer-column ul li a {
    color: inherit;
    text-decoration: none;
    transition: color 0.2s ease;
}

.footer-column ul li a:hover {
    color: #ffffff;
}

/* Quick Contact 区域：仅保留图标和文字，不加背景和边框 */
.footer-contact-card {
    background: none;
    border: none;
    padding: 0;
    box-shadow: none;
}

.footer-contact-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    margin-bottom: 22px;
}

.footer-contact-icon {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: radial-gradient(circle at 30% 0%, #4fd1c5, #38b2ac);
    color: #0b1220;
    font-size: 16px;
    flex-shrink: 0;
}

.footer-contact-label {
    font-size: 13px;
    font-weight: 600;
    color: rgba(226, 232, 240, 0.9);
    margin-bottom: 4px;
}

.footer-contact-text {
    font-size: 14px;
    color: rgba(203, 213, 225, 0.9);
    margin-top: 2px;
    line-height: 1.6;
}

/* Mail Us 表单布局：保持简洁，无额外背景块 */
.footer-mail-form {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.footer-mail-textarea,
.footer-mail-input {
    width: 100%;
    padding: 14px 16px;
    border-radius: 8px;
    border: none;
    outline: none;
    font-size: 14px;
    color: #1a202c;
    background-color: #ffffff;
    resize: vertical;
}

.footer-mail-textarea {
    min-height: 100px;
}

.footer-mail-input {
    min-height: auto;
}

.footer-mail-textarea::placeholder,
.footer-mail-input::placeholder {
    color: #a0aec0;
}

.footer-mail-button {
    width: 130px;
    padding: 12px 0;
    border-radius: 6px;
    border: none;
    cursor: pointer;
    background-color: #f97316;
    color: #fff;
    font-weight: 600;
    font-size: 15px;
    transition: background-color 0.2s ease, transform 0.1s ease;
}

.footer-mail-button:hover {
    background-color: #ea580c;
    transform: translateY(-2px);
}

.footer-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding-top: 30px;
    margin-top: 20px;
    border-top: 1px solid rgba(226, 232, 240, 0.1);
    color: rgba(226, 232, 240, 0.65);
    font-size: 13px;
}

.footer-bottom p {
    margin: 0;
}

/* 页面标题横幅 */
.page-hero {
    background: url(images/65446.jpg);
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    color: white;
    padding: 180px 20px 120px;
    text-align: center;
    position: relative;
    overflow: hidden;
    min-height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.page-hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><rect width="100" height="100" fill="%231a365d"/></svg>');
    opacity: 0.3;
    z-index: 1;
}

.page-hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: 1;
}

.page-title {
    position: relative;
    z-index: 2;
    font-size: 72px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 4px;
    margin: 0 auto;
    width: 100%;
}

/* ============================================
   About 页面独立样式
   ============================================ */
.about-hero {
    background: url(images/65446.jpg);
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    color: white;
    padding: 200px 20px 150px;
    text-align: center;
    position: relative;
    overflow: hidden;
    min-height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.about-hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><rect width="100" height="100" fill="%231a365d"/></svg>');
    opacity: 0.3;
    z-index: 1;
}

.about-hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: 1;
}

.about-title {
    position: relative;
    z-index: 2;
    font-size: 72px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 4px;
    margin: 0 auto;
    width: 100%;
}

.about-content {
    padding: 35px 20px;
    background: #fff;
}

.about-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 100px;
    align-items: center;
}

.about-left {
    max-width: 100%;
    padding-right: 20px;
}

.about-label {
    font-size: 13px;
    color: #e53e3e;
    text-transform: uppercase;
    letter-spacing: 3px;
    margin-bottom: 20px;
    font-weight: 600;
    display: inline-block;
    padding-bottom: 8px;
    border-bottom: 2px solid #e53e3e;
}

.about-right {
    max-width: 100%;
}

.about-right h3 {
    font-size: 16px;
    line-height: 1.9;
    color: #4a5568;
    margin-bottom: 20px;
}

/* ============================================
   Product 页面独立样式
   ============================================ */
.product-hero {
    background-color: #0b1220;
    background-image: url('images/IMG_5069-.jpg');
    background-repeat: no-repeat;
    background-position: center center;
    background-size: cover;
    background-attachment: fixed;
    color: white;
    padding: 140px 20px 90px;
    text-align: center;
    position: relative;
    overflow: hidden;
    height: 900px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.product-hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><rect width="100" height="100" fill="%231a365d"/></svg>');
    opacity: 0.3;
    z-index: 1;
}

.product-hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: 1;
}

.product-title {
    position: relative;
    z-index: 2;
    font-size: 56px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 4px;
    margin: 0 auto;
    width: 100%;
    text-shadow: 2px 2px 8px rgba(0, 0, 0, 0.8), 0 0 20px rgba(0, 0, 0, 0.5);
    animation: fadeInUp 0.8s ease-out;
}

/* 统一页面大标题文字阴影效果 */
.hero-title,
.about-title,
.projects-title,
.contact-title,
.page-title {
    text-shadow: 2px 2px 8px rgba(0, 0, 0, 0.8), 0 0 20px rgba(0, 0, 0, 0.5);
}

.product-content {
    padding: 40px 20px 60px;
    background: #ffffff;
}

.product-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 100px;
    align-items: center;
}

.product-left {
    max-width: 100%;
    padding-right: 20px;
}

.product-label {
    font-size: 14px;
    color: #2c5282;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 15px;
    font-weight: 600;
}

.product-section-title {
    font-size: 42px;
    font-weight: 700;
    color: #1a202c;
    line-height: 1.3;
    margin-bottom: 30px;
}

.product-left p {
    font-size: 16px;
    line-height: 1.9;
    color: #4a5568;
    margin-bottom: 20px;
}

.product-right {
    max-width: 100%;
}

.product-image-placeholder {
    width: 100%;
    display: block;
}

.product-image {
    width: 100%;
    height: auto;
    border-radius: 14px;
    object-fit: contain;
    box-shadow: 0 16px 40px rgba(15, 23, 42, 0.28);
    background: linear-gradient(135deg, #edf2f7 0%, #cbd5e0 100%);
    display: block;
}

.product-innovations {
    padding: 100px 20px;
    background: #f7fafc;
}

.product-section-header {
    text-align: center;
    margin-bottom: 60px;
}

.product-section-label {
    font-size: 14px;
    color: #e53e3e;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 15px;
    font-weight: 600;
}

.product-service-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 36px;
    margin-bottom: 60px;
}

.product-service-item {
    padding: 38px 32px 42px;
    background: radial-gradient(circle at 0 0, rgba(226, 232, 240, 0.9), transparent 55%),
                radial-gradient(circle at 100% 100%, rgba(237, 242, 247, 0.9), transparent 55%),
                #ffffff;
    border-radius: 20px;
    border: 1px solid rgba(226, 232, 240, 0.9);
    box-shadow: 0 18px 40px rgba(15, 23, 42, 0.16);
    transition: transform 0.35s ease, box-shadow 0.35s ease, border-color 0.35s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.product-service-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 24px 55px rgba(15, 23, 42, 0.24);
    border-color: rgba(229, 62, 62, 0.45);
}

.product-service-item h3 {
    font-size: 20px;
    letter-spacing: 1.5px;
    text-transform: uppercase;
    color: #1a202c;
    margin-bottom: 18px;
    font-weight: 700;
}

.product-service-item p {
    color: #718096;
    line-height: 1.7;
    font-size: 15px;
}

/* 产品系列样式 */
.product-series {
    margin-bottom: 32px;
}

.product-series:last-child {
    margin-bottom: 0;
}

.product-series-wrapper {
    display: grid;
    grid-template-columns: 0.6fr 1.4fr;
    gap: 24px;
    align-items: center;
    padding: 10px 0;
}

.product-series-wrapper.reverse {
    direction: rtl;
}

.product-series-wrapper.reverse > * {
    direction: ltr;
}

.product-series-image {
    width: 100%;
    display: flex;
    justify-content: center;
}

.product-series-img {
    width: min(100%, 620px);
    height: auto;
    max-height: 600px;
    border-radius: 14px;
    object-fit: contain;
    display: block;
}


.product-series-content {
    max-width: 100%;
}

.product-series-content .product-label {
    font-size: 13px;
    color: #2c5282;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 10px;
    font-weight: 600;
}

.product-series-content .product-section-title {
    font-size: 30px;
    font-weight: 700;
    color: #1a202c;
    line-height: 1.25;
    margin-bottom: 12px;
}

.product-series-content p {
    font-size: 15px;
    line-height: 1.6;
    color: #4a5568;
    margin-bottom: 10px;
}

.product-series-details {
    margin-top: 10px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 10px;
}

.series-item {
    margin-bottom: 0;
    padding: 10px;
    background: rgba(237, 242, 247, 0.5);
    border-radius: 10px;
    border-left: 4px solid #2c5282;
}

.series-item:last-child {
    margin-bottom: 0;
}

.series-item h3 {
    font-size: 18px;
    font-weight: 700;
    color: #1a202c;
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.series-item p {
    font-size: 14px;
    line-height: 1.7;
    color: #4a5568;
    margin-bottom: 6px;
}

.series-item p:last-child {
    margin-bottom: 0;
}

/* 产品表格布局标题与表格样式（还原画册效果） */
.series-main-title {
    font-size: 20px;
    font-weight: 700;
    color: #009245;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 14px;
}

.series-subtitle {
    font-size: 16px;
    font-weight: 700;
    color: #333333;
    text-transform: uppercase;
    margin: 18px 0 8px;
}

.product-data-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
    margin-bottom: 10px;
    table-layout: fixed;
}

.product-data-table th,
.product-data-table td {
    border: 1px solid #c4c4c4;
    padding: 6px 8px;
    vertical-align: middle;
    text-align: center;
}

.product-data-table thead th {
    background-color: #f7f7f7;
    color: #333333;
    font-weight: 700;
}

.product-data-table tbody td:last-child {
    font-size: 12px;
    line-height: 1.6;
    text-align: left;
}

/* ============================================
   Projects 页面独立样式
   ============================================ */
.projects-hero {
    background: url(images/65446.jpg);
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    color: white;
    padding: 200px 20px 150px;
    text-align: center;
    position: relative;
    overflow: hidden;
    min-height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.projects-hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><rect width="100" height="100" fill="%231a365d"/></svg>');
    opacity: 0.3;
    z-index: 1;
}

.projects-hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: 1;
}

.projects-title {
    position: relative;
    z-index: 2;
    font-size: 72px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 4px;
    margin: 0 auto;
    width: 100%;
}

.projects-content {
    padding: 100px 20px;
    background: #fff;
}

.projects-header {
    max-width: 720px;
    margin: 0 auto 60px;
    text-align: center;
}

.projects-label {
    font-size: 14px;
    color: #2c5282;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 15px;
    font-weight: 600;
}

.projects-section-title {
    font-size: 42px;
    font-weight: 700;
    color: #1a202c;
    line-height: 1.3;
    margin-bottom: 25px;
}

.projects-intro {
    margin-top: 18px;
    font-size: 16px;
    line-height: 1.8;
    color: #4a5568;
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 28px;
}

.projects-card {
    background: #f7fafc;
    border-radius: 18px;
    overflow: hidden;
    box-shadow: 0 18px 45px rgba(15, 23, 42, 0.12);
    display: flex;
    flex-direction: column;
}

.projects-card-media {
    height: 220px;
    background-size: cover;
    background-position: center;
}

.projects-card--aerospace .projects-card-media {
    background-image: url('https://images.pexels.com/photos/3140201/pexels-photo-3140201.jpeg?auto=compress&cs=tinysrgb&w=900&h=600&fit=crop');
}

.projects-card--oil .projects-card-media {
    background-image: url('https://images.pexels.com/photos/9793811/pexels-photo-9793811.jpeg?auto=compress&cs=tinysrgb&w=900&h=600&fit=crop');
}

.projects-card--automotive .projects-card-media {
    background-image: url('https://images.pexels.com/photos/4489734/pexels-photo-4489734.jpeg?auto=compress&cs=tinysrgb&w=900&h=600&fit=crop');
}

.projects-card-body {
    padding: 26px 26px 28px;
}

.projects-card-title {
    font-size: 20px;
    font-weight: 600;
    color: #1a202c;
    margin-bottom: 12px;
}

.projects-card-text {
    font-size: 15px;
    line-height: 1.8;
    color: #4a5568;
}

/* News 页面列表样式（复用 projects 卡片风格） */
.news-section {
    background: #ffffff;
}

.projects-grid-large {
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    align-items: stretch;
}

.news-item {
    display: flex;
    flex-direction: column;
}

.news-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    font-size: 13px;
    color: #718096;
    margin-bottom: 10px;
}

.news-date {
    font-weight: 600;
}


.news-more {
    display: inline-block;
    margin-top: 14px;
    font-size: 14px;
    color: #2c5282;
    text-decoration: none;
    font-weight: 500;
}

.news-more:hover {
    text-decoration: underline;
}

/* News 分页 */
.news-pagination {
    margin-top: 40px;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
}

.news-pagination .page-link {
    min-width: 38px;
    padding: 8px 14px;
    border-radius: 999px;
    border: 1px solid #e2e8f0;
    background: #ffffff;
    font-size: 14px;
    color: #4a5568;
    text-decoration: none;
    text-align: center;
    transition: all 0.2s ease;
}

.news-pagination .page-link:hover {
    border-color: #2c5282;
    color: #2c5282;
}

.news-pagination .page-link.active {
    background: #2c5282;
    border-color: #2c5282;
    color: #ffffff;
    font-weight: 600;
}

.news-pagination .page-link.disabled {
    opacity: 0.4;
    cursor: default;
    pointer-events: none;
}

/* News 详情页样式 */
.news-detail-section {
    padding: 100px 20px;
    background: #fff;
}

.news-detail-wrapper {
    max-width: 900px;
    margin: 0 auto;
}

.news-back-link {
    display: inline-flex;
    align-items: center;
    color: #2c5282;
    text-decoration: none;
    font-size: 15px;
    font-weight: 500;
    margin-bottom: 30px;
    transition: color 0.3s ease;
}

.news-back-link:hover {
    color: #1a365d;
}

.news-detail-article {
    background: #fff;
    padding: 0;
}

.news-detail-loading {
    text-align: center;
    padding: 60px 20px;
    color: #718096;
    font-size: 16px;
}

.news-detail-error {
    text-align: center;
    padding: 60px 20px;
}

.news-detail-error h2 {
    font-size: 28px;
    color: #1a202c;
    margin-bottom: 15px;
}

.news-detail-error p {
    color: #718096;
    margin-bottom: 25px;
}

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

.news-detail-date {
    display: inline-block;
    font-size: 14px;
    color: #718096;
    font-weight: 500;
}

.news-detail-title {
    font-size: 42px;
    font-weight: 700;
    color: #1a202c;
    line-height: 1.3;
    margin-bottom: 35px;
}

.news-detail-content {
    font-size: 16px;
    line-height: 1.9;
    color: #4a5568;
}

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

.news-detail-content p:last-child {
    margin-bottom: 0;
}

/* ============================================
   Contact 页面独立样式
   ============================================ */
.contact-hero {
    background-image: url(images/jsuz\ \(1\).jpg);
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    color: white;
    padding: 200px 20px 150px;
    text-align: center;
    position: relative;
    overflow: hidden;
    min-height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.contact-hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><rect width="100" height="100" fill="%231a365d"/></svg>');
    opacity: 0.3;
    z-index: 1;
}

.contact-hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: 1;
}

.contact-title {
    position: relative;
    z-index: 2;
    font-size: 72px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 4px;
    margin: 0 auto;
    width: 100%;
}

.contact-content {
    padding: 100px 20px;
    background:#fff;
}

.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    align-items: stretch;
}

.service-intro {
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}

.service-intro p {
    font-size: 16px;
    line-height: 1.8;
    margin-bottom: 20px;
    color: #4a5568;
}

/* Innovations 部分 */
.innovations {
    padding: 100px 20px;
    background: #f7fafc;
}

/* Contact 部分 */
.contact-info {
    margin-top: 30px;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 15px;
    margin-bottom: 20px;
}

.contact-icon {
    font-size: 20px;
    margin-top: 2px;
}

.contact-item p {
    color: #4a5568;
    font-size: 16px;
    line-height: 1.6;
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 25px;
}

.form-group {
    width: 100%;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: #1a202c;
    font-weight: 500;
    font-size: 14px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 15px;
    border: 1px solid #e2e8f0;
    border-radius: 4px;
    font-size: 15px;
    font-family: inherit;
    transition: border-color 0.3s;
    background: white;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #2c5282;
}

.form-group textarea {
    resize: vertical;
    min-height: 150px;
}

.contact-form .btn-primary {
    align-self: flex-start;
}

/* 新的 Contact 卡片样式 */
.contact-cards {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    align-items: stretch;
}

.contact-card {
    background: #fff;
    border-radius: 12px;
    padding: 34px;
    box-shadow: 0 8px 30px rgba(30,40,60,0.08);
    border: 1px solid rgba(0,0,0,0.03);
    display: flex;
    flex-direction: column;
    height: 100%;
}

.left-card .content-heading,
.right-card .content-heading {
    font-size: 24px;
    margin-bottom: 12px;
}

.contact-card .intro-text {
    color: #4a5568;
    margin-bottom: 22px;
}

.contact-item {
    display: flex;
    gap: 14px;
    margin-bottom: 18px;
}

.contact-icon {
    font-size: 20px;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(180deg, #fff, #fff);
    border-radius: 50%;
}

.contact-label {
    font-size: 13px;
    color: #2d3748;
    font-weight: 600;
}

.contact-value {
    font-size: 15px;
    color: #4a5568;
    margin-top: 4px;
}

.contact-note {
    margin-top: 18px;
    padding: 16px;
    border-radius: 8px;
    border: 1px dashed rgba(45,55,72,0.08);
    background: linear-gradient(180deg, rgba(245,245,247,0.9), rgba(255,255,255,0.9));
    color: #718096;
    font-size: 14px;
}

.right-card .contact-form .row {
    display: flex;
    gap: 16px;
}

.right-card .contact-form {
    display: flex;
    flex-direction: column;
    flex: 1 1 auto;
}

.form-group.half {
    flex: 1;
}

.right-card .contact-form .small {
    margin-bottom: 12px;
}

.muted {
    color: #718096;
    font-size: 13px;
}

.send-btn {
    background: linear-gradient(180deg, #f6a623 0%, #f08a00 100%);
    color: #2d1b00;
    padding: 12px 26px;
    border-radius: 28px;
    box-shadow: 0 10px 30px rgba(240,138,0,0.18);
    border: none;
    font-weight: 600;
    margin-top: 18px;
    align-self: flex-start;
}

@media (max-width: 968px) {
    .contact-cards {
        grid-template-columns: 1fr;
    }
    .right-card .contact-form .row {
        flex-direction: column;
    }
}

/* Service 右侧图片容器 */
.image-placeholder {
    width: 100%;
    display: block;
}

.service-image {
    width: 100%;
    height: auto;
    border-radius: 14px;
    object-fit: contain;
    box-shadow: 0 16px 40px rgba(15, 23, 42, 0.28);
    background: linear-gradient(135deg, #edf2f7 0%, #cbd5e0 100%);
    display: block;
}

/* Certification 部分 - 上下布局 */
.certification-section .certification-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 40px;
    max-width: 100%;
}

.certification-section .projects-grid {
    display: flex;
    gap: 30px;
    justify-content: center;
}

.certification-section .certification-item {
    padding: 0;
    /* about 页面证书图片比原来稍微大一点，参考首页大小 */
    max-width: 260px;
}

.certification-section .certification-image {
    width: 100%;
    height: auto;
}

.certification-title {
    font-size: 32px;
    font-weight: 700;
    color: #1a202c;
    text-transform: uppercase;
    letter-spacing: 3px;
    text-align: center;
}

.certification-image {
    width: 100%;
    max-width: 800px;
    height: auto;
    display: block;
    border-radius: 12px;
    box-shadow: 0 20px 50px rgba(15, 23, 42, 0.15);
}

/* 响应式设计 */
@media (max-width: 968px) {
    /* About 页面响应式 */
    .about-wrapper {
        grid-template-columns: 1fr;
        gap: 50px;
    }

    /* Product 页面响应式 */
    .product-wrapper {
        grid-template-columns: 1fr;
        gap: 50px;
    }

    .product-service-grid {
        grid-template-columns: 1fr;
    }

    .product-series-wrapper {
        grid-template-columns: 1fr;
        gap: 28px;
    }

    /* About 页面证书区域在小屏幕改为一列竖排，图片略小 */
    .certification-section .projects-grid {
        flex-direction: column;
        align-items: center;
    }

    .certification-section .certification-item {
        max-width: 260px;
    }

    .product-series-wrapper.reverse {
        direction: ltr;
    }

    .product-series-img {
        width: 100%;
        max-height: 320px;
    }

    /* Projects 页面响应式 */
    .projects-grid {
        grid-template-columns: 1fr;
    }

    /* Contact 页面响应式 */
    .contact-wrapper {
        grid-template-columns: 1fr;
    }

    .content-wrapper {
        grid-template-columns: 1fr;
        gap: 50px;
    }

    .projects-grid-large {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .menu-toggle {
        display: block;
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background: rgba(26, 32, 44, 0.98);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        padding: 30px 0;
        gap: 20px;
    }

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

    .language-selector {
        margin-left: 15px;
    }

    .lang-select {
        padding: 6px 30px 6px 10px;
        font-size: 13px;
    }

    .hero-title {
        font-size: 42px;
    }

    /* About 页面响应式 */
    .about-title {
        font-size: 48px;
    }

    .about-label {
        margin-left: 0;
    }

    /* Product 页面响应式 */
    .product-title {
        font-size: 48px;
    }

    .product-section-title {
        font-size: 32px;
    }

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

    /* Projects 页面响应式 */
    .projects-title {
        font-size: 48px;
    }

    .projects-section-title {
        font-size: 32px;
    }

    /* Contact 页面响应式 */
    .contact-title {
        font-size: 48px;
    }

    .page-title {
        font-size: 48px;
    }

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

    .content-heading {
        font-size: 26px;
    }

    .service-grid,
    .projects-grid {
        grid-template-columns: 1fr;
    }

    .cta h2 {
        font-size: 32px;
    }

    .footer-content {
        flex-direction: column;
        gap: 24px;
    }

    .image-placeholder {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 968px) {
    .footer-content {
        flex-wrap: wrap;
        gap: 40px;
    }
    .footer-brand {
        flex-basis: 100%;
        padding-right: 0;
    }
    .footer-column,
    .footer-contact-column,
    .footer-mail-column {
        flex-basis: calc(50% - 20px);
    }
}

@media (max-width: 480px) {
    .hero {
        /* 小屏幕仍然用 cover，避免图片太小导致主体看不清 */
        background-size: cover;
        padding: 160px 20px 100px;
        min-height: 500px;
    }

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

    .hero-subtitle {
        font-size: 12px;
    }

    section {
        padding: 80px 20px;
    }

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

    /* About 页面响应式 */
    .about-title {
        font-size: 36px;
        letter-spacing: 2px;
    }

    .about-hero {
        padding: 140px 20px 80px;
        min-height: 300px;
    }

    .about-content {
        padding: 80px 20px;
    }

    /* Product 页面响应式 */
    .product-title {
        font-size: 36px;
        letter-spacing: 2px;
    }

    .product-hero {
        padding: 140px 20px 80px;
        min-height: 300px;
        /* 移动端 fixed 可能导致抖动/裁切问题（保留原逻辑） */
        background-attachment: scroll;
    }

    .product-content {
        padding: 60px 20px;
    }

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

    .product-series {
        margin-bottom: 40px;
    }

    .product-series-wrapper {
        padding: 18px 0;
    }

    .product-series-content .product-section-title {
        font-size: 24px;
    }

    /* Projects 页面响应式 */
    .projects-title {
        font-size: 36px;
        letter-spacing: 2px;
    }

    .projects-hero {
        padding: 140px 20px 80px;
        min-height: 300px;
    }

    .projects-content {
        padding: 80px 20px;
    }

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

    /* Contact 页面响应式 */
    .contact-title {
        font-size: 36px;
        letter-spacing: 2px;
    }

    .contact-hero {
        padding: 140px 20px 80px;
        min-height: 300px;
    }

    .contact-content {
        padding: 80px 20px;
    }

    .page-title {
        font-size: 36px;
        letter-spacing: 2px;
    }

    .page-hero {
        padding: 140px 20px 80px;
        min-height: 300px;
    }
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}