:root {
    --color-cream: #e7e7de;
    --color-teal: #008891;
    --color-deep-teal: #00587a;
    --color-navy: #0f3057;
    --color-white: #ffffff;
    --color-dark: #1a1a2e;
    --color-gray-light: #f5f5f0;
    --color-gray: #6b7280;
    --color-border: #d4d4c8;
    --shadow-sm: 0 2px 8px rgba(15, 48, 87, 0.06);
    --shadow-md: 0 4px 20px rgba(15, 48, 87, 0.10);
    --shadow-lg: 0 8px 40px rgba(15, 48, 87, 0.14);
    --shadow-xl: 0 16px 56px rgba(15, 48, 87, 0.18);
    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 20px;
    --radius-xl: 28px;
    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-smooth: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    --font-heading: 'Georgia', 'Noto Serif SC', 'STSong', 'Songti SC', 'SimSun', serif;
    --font-body: 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
    --max-width: 1260px;
    --nav-height: 72px;
    --nav-height-mobile: 60px;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

body {
    font-family: var(--font-body);
    background-color: var(--color-cream);
    color: var(--color-navy);
    line-height: 1.7;
    min-height: 100vh;
    overflow-x: hidden;
    letter-spacing: 0.01em;
}

/* ============ 顶部导航栏 - 100%宽度 ============ */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--nav-height);
    background: var(--color-white);
    z-index: 1000;
    border-bottom: 1px solid transparent;
    transition: all var(--transition-smooth);
    box-shadow: var(--shadow-sm);
}

.site-header.scrolled {
    box-shadow: var(--shadow-lg);
    border-bottom-color: rgba(15, 48, 87, 0.06);
    background: rgba(255, 255, 255, 0.97);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
}

.header-inner {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 28px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    flex-shrink: 0;
    z-index: 1001;
}

.logo-icon {
    width: 44px;
    height: 44px;
    background: var(--color-navy);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-cream);
    font-family: var(--font-heading);
    font-size: 1.35rem;
    font-weight: 700;
    letter-spacing: 0.02em;
    transition: background var(--transition-fast);
    flex-shrink: 0;
}

.logo-area:hover .logo-icon {
    background: var(--color-deep-teal);
}

.logo-text {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--color-navy);
    letter-spacing: 0.03em;
    white-space: nowrap;
    transition: color var(--transition-fast);
}

.logo-area:hover .logo-text {
    color: var(--color-deep-teal);
}

/* 桌面端导航菜单 */
.main-nav {
    display: flex;
    align-items: center;
    gap: 6px;
    list-style: none;
}

.main-nav li {
    position: relative;
}

.main-nav a {
    display: block;
    padding: 10px 18px;
    text-decoration: none;
    color: var(--color-navy);
    font-size: 0.95rem;
    font-weight: 500;
    letter-spacing: 0.02em;
    border-radius: 24px;
    transition: all var(--transition-fast);
    white-space: nowrap;
    position: relative;
}

.main-nav a:hover,
.main-nav a:focus-visible {
    color: var(--color-teal);
    background: rgba(0, 136, 145, 0.06);
    outline: none;
}

.main-nav a.active {
    color: var(--color-teal);
    font-weight: 600;
}

.main-nav a.active::after {
    content: '';
    position: absolute;
    bottom: 4px;
    left: 50%;
    transform: translateX(-50%);
    width: 18px;
    height: 3px;
    background: var(--color-teal);
    border-radius: 3px;
}

/* 移动端菜单按钮 */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    z-index: 1001;
    padding: 8px;
    background: none;
    border: none;
    width: 40px;
    height: 32px;
    justify-content: center;
    align-items: center;
}

.menu-toggle span {
    display: block;
    width: 26px;
    height: 2.5px;
    background: var(--color-navy);
    border-radius: 3px;
    transition: all var(--transition-smooth);
    transform-origin: center;
}

#menu-checkbox {
    display: none;
}

#menu-checkbox:checked~.menu-toggle span:nth-child(1) {
    transform: translateY(7.5px) rotate(45deg);
}

#menu-checkbox:checked~.menu-toggle span:nth-child(2) {
    opacity: 0;
    transform: scaleX(0);
}

#menu-checkbox:checked~.menu-toggle span:nth-child(3) {
    transform: translateY(-7.5px) rotate(-45deg);
}

/* 移动端导航面板 */
.mobile-nav-panel {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: var(--color-white);
    z-index: 999;
    padding: calc(var(--nav-height-mobile) + 30px) 28px 40px;
    flex-direction: column;
    gap: 8px;
    overflow-y: auto;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-smooth);
}

#menu-checkbox:checked~.mobile-nav-panel {
    opacity: 1;
    pointer-events: auto;
}

.mobile-nav-panel a {
    display: block;
    padding: 15px 20px;
    text-decoration: none;
    color: var(--color-navy);
    font-size: 1.1rem;
    font-weight: 500;
    letter-spacing: 0.03em;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    border: 1px solid transparent;
}

.mobile-nav-panel a:hover,
.mobile-nav-panel a:focus-visible {
    background: rgba(0, 136, 145, 0.05);
    color: var(--color-teal);
    border-color: rgba(0, 136, 145, 0.15);
    outline: none;
}

/* ============ Hero 区域 ============ */
.hero-section {
    margin-top: var(--nav-height);
    width: 100%;
    min-height: 580px;
    background: var(--color-navy);
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    padding: 60px 24px;
}

.hero-bg-pattern {
    position: absolute;
    inset: 0;
    opacity: 0.07;
    background-image:
        radial-gradient(circle at 20% 30%, #ffffff 1px, transparent 1px),
        radial-gradient(circle at 70% 60%, #ffffff 1px, transparent 1px),
        radial-gradient(circle at 40% 80%, #ffffff 1.5px, transparent 1.5px);
    background-size: 60px 60px, 80px 80px, 100px 100px;
    pointer-events: none;
}

.hero-accent-line {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--color-teal), var(--color-deep-teal), var(--color-teal));
    opacity: 0.7;
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    max-width: 780px;
    color: var(--color-white);
}

.hero-badge {
    display: inline-block;
    padding: 8px 20px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.25);
    border-radius: 40px;
    font-size: 0.9rem;
    letter-spacing: 0.06em;
    margin-bottom: 24px;
    color: var(--color-cream);
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
}

.hero-content h1 {
    font-family: var(--font-heading);
    font-size: 3.2rem;
    font-weight: 700;
    letter-spacing: 0.05em;
    margin-bottom: 18px;
    color: #ffffff;
    line-height: 1.25;
    text-shadow: 0 2px 12px rgba(0, 0, 0, 0.2);
}

.hero-content .hero-subtitle {
    font-size: 1.15rem;
    color: rgba(255, 255, 255, 0.85);
    letter-spacing: 0.04em;
    line-height: 1.7;
    margin-bottom: 36px;
    max-width: 620px;
    margin-left: auto;
    margin-right: auto;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    justify-content: center;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: 40px;
    font-size: 0.95rem;
    font-weight: 600;
    letter-spacing: 0.03em;
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition-smooth);
    border: 2px solid transparent;
    white-space: nowrap;
}

.btn-primary {
    background: var(--color-teal);
    color: #ffffff;
    border-color: var(--color-teal);
    box-shadow: 0 6px 24px rgba(0, 136, 145, 0.35);
}

.btn-primary:hover {
    background: var(--color-deep-teal);
    border-color: var(--color-deep-teal);
    box-shadow: 0 10px 32px rgba(0, 136, 145, 0.45);
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    color: #ffffff;
    border-color: rgba(255, 255, 255, 0.5);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.12);
    border-color: rgba(255, 255, 255, 0.8);
    transform: translateY(-2px);
}

.hero-img-wrapper {
    position: relative;
    z-index: 2;
    margin-top: 40px;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-xl);
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.hero-img-wrapper img {
    width: 100%;
    height: auto;
    display: block;
    object-fit: cover;
    aspect-ratio: 16 / 7;
}

/* ============ 通用板块样式 ============ */
.section {
    padding: 80px 24px;
    width: 100%;
}

.section-inner {
    max-width: var(--max-width);
    margin: 0 auto;
}

.section-label {
    display: inline-block;
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--color-teal);
    margin-bottom: 10px;
    position: relative;
    padding-left: 32px;
}

.section-label::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 22px;
    height: 2px;
    background: var(--color-teal);
    border-radius: 2px;
}

.section-title {
    font-family: var(--font-heading);
    font-size: 2.2rem;
    font-weight: 700;
    letter-spacing: 0.03em;
    color: var(--color-navy);
    margin-bottom: 16px;
    line-height: 1.3;
}

.section-desc {
    font-size: 1.05rem;
    color: var(--color-gray);
    max-width: 640px;
    line-height: 1.75;
    letter-spacing: 0.02em;
}

/* 交替背景 */
.section-alt {
    background: var(--color-white);
}

.section-cream {
    background: var(--color-cream);
}

/* ============ 企业简介 ============ */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 56px;
    align-items: center;
}

.about-image {
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    position: relative;
}

.about-image img {
    width: 100%;
    height: auto;
    display: block;
    object-fit: cover;
    aspect-ratio: 4 / 3;
    transition: transform var(--transition-smooth);
}

.about-image:hover img {
    transform: scale(1.03);
}

.about-image::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--color-teal), var(--color-deep-teal));
    opacity: 0.8;
}

.about-text .highlight-box {
    background: var(--color-white);
    border-left: 5px solid var(--color-teal);
    padding: 20px 24px;
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
    margin: 20px 0;
    box-shadow: var(--shadow-sm);
    font-style: italic;
    color: var(--color-deep-teal);
    letter-spacing: 0.02em;
    line-height: 1.7;
}

.about-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px;
    margin-top: 22px;
}

.feature-item {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    font-size: 0.95rem;
    color: var(--color-navy);
    letter-spacing: 0.02em;
}

.feature-dot {
    width: 10px;
    height: 10px;
    min-width: 10px;
    border-radius: 50%;
    background: var(--color-teal);
    margin-top: 6px;
    flex-shrink: 0;
}

/* ============ 研究领域（产品介绍） ============ */
.research-cards {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 22px;
    margin-top: 36px;
}

.research-card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 32px 24px;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-smooth);
    border: 1px solid transparent;
    position: relative;
    overflow: hidden;
}

.research-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-6px);
    border-color: rgba(0, 136, 145, 0.2);
}

.research-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--color-teal), var(--color-deep-teal));
    opacity: 0;
    transition: opacity var(--transition-smooth);
}

.research-card:hover::before {
    opacity: 1;
}

.research-card-icon {
    width: 52px;
    height: 52px;
    border-radius: var(--radius-sm);
    background: rgba(0, 136, 145, 0.08);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 18px;
    transition: background var(--transition-fast);
}

.research-card:hover .research-card-icon {
    background: rgba(0, 136, 145, 0.18);
}

.research-card-icon svg {
    width: 26px;
    height: 26px;
    color: var(--color-teal);
}

.research-card h3 {
    font-family: var(--font-heading);
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--color-navy);
    margin-bottom: 8px;
    letter-spacing: 0.03em;
}

.research-card p {
    font-size: 0.9rem;
    color: var(--color-gray);
    line-height: 1.6;
    letter-spacing: 0.02em;
}

/* ============ Brand 品牌/合作伙伴 ============ */
.brand-scroll {
    display: flex;
    gap: 28px;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    margin-top: 36px;
}

.brand-item {
    background: var(--color-white);
    border-radius: var(--radius-md);
    padding: 22px 28px;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-smooth);
    text-align: center;
    min-width: 130px;
    flex-shrink: 0;
    border: 1px solid var(--color-border);
}

.brand-item:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-4px);
    border-color: var(--color-teal);
}

.brand-item img {
    width: auto;
    height: 48px;
    max-width: 140px;
    object-fit: contain;
    display: block;
    margin: 0 auto 10px;
    opacity: 0.8;
    transition: opacity var(--transition-fast);
}

.brand-item:hover img {
    opacity: 1;
}

.brand-item span {
    display: block;
    font-size: 0.85rem;
    color: var(--color-gray);
    letter-spacing: 0.03em;
    font-weight: 500;
}

/* ============ 新闻资讯 ============ */
.news-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-top: 36px;
}

.news-card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-smooth);
    border: 1px solid transparent;
    display: flex;
    flex-direction: column;
}

.news-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-5px);
    border-color: rgba(0, 136, 145, 0.2);
}

.news-card-img {
    width: 100%;
    aspect-ratio: 16 / 10;
    overflow: hidden;
    position: relative;
}

.news-card-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform var(--transition-smooth);
}

.news-card:hover .news-card-img img {
    transform: scale(1.06);
}

.news-card-body {
    padding: 22px 20px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.news-card-date {
    font-size: 0.8rem;
    color: var(--color-teal);
    letter-spacing: 0.05em;
    font-weight: 600;
    margin-bottom: 8px;
}

.news-card h3 {
    font-family: var(--font-heading);
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--color-navy);
    margin-bottom: 8px;
    line-height: 1.4;
    letter-spacing: 0.02em;
}

.news-card p {
    font-size: 0.88rem;
    color: var(--color-gray);
    line-height: 1.6;
    flex: 1;
    letter-spacing: 0.02em;
}

.news-card-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-top: 14px;
    color: var(--color-teal);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.9rem;
    letter-spacing: 0.03em;
    transition: gap var(--transition-fast);
}

.news-card-link:hover {
    gap: 10px;
    color: var(--color-deep-teal);
}

.news-card-link .arrow {
    transition: transform var(--transition-fast);
}

.news-card-link:hover .arrow {
    transform: translateX(3px);
}

/* ============ 数据统计 ============ */
.stats-row {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    margin-top: 36px;
    text-align: center;
}

.stat-item {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 32px 20px;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-smooth);
    border: 1px solid transparent;
}

.stat-item:hover {
    box-shadow: var(--shadow-md);
    border-color: rgba(0, 136, 145, 0.2);
    transform: translateY(-3px);
}

.stat-number {
    font-family: var(--font-heading);
    font-size: 2.8rem;
    font-weight: 700;
    color: var(--color-teal);
    letter-spacing: 0.02em;
    line-height: 1;
    margin-bottom: 8px;
}

.stat-label {
    font-size: 0.95rem;
    color: var(--color-gray);
    letter-spacing: 0.04em;
    font-weight: 500;
}

/* ============ 公司地址 & 联系我们 ============ */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    margin-top: 36px;
}

.contact-info-card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 32px 28px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
    transition: all var(--transition-smooth);
}

.contact-info-card:hover {
    box-shadow: var(--shadow-md);
    border-color: rgba(0, 136, 145, 0.2);
}

.contact-info-card h3 {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--color-navy);
    margin-bottom: 18px;
    letter-spacing: 0.03em;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--color-cream);
}

.address-block {
    margin-bottom: 20px;
}

.address-block .addr-title {
    font-weight: 600;
    color: var(--color-teal);
    font-size: 0.9rem;
    letter-spacing: 0.05em;
    margin-bottom: 4px;
    display: flex;
    align-items: center;
    gap: 6px;
}

.address-block .addr-detail {
    font-size: 0.95rem;
    color: var(--color-navy);
    line-height: 1.7;
    letter-spacing: 0.02em;
    padding-left: 20px;
}

.contact-methods {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 18px;
}

.contact-method-item {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.95rem;
    color: var(--color-navy);
    letter-spacing: 0.02em;
}

.contact-icon-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--color-teal);
    flex-shrink: 0;
}

/* 联系表单 */
.contact-form-card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 32px 28px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
    transition: all var(--transition-smooth);
}

.contact-form-card h3 {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--color-navy);
    margin-bottom: 18px;
    letter-spacing: 0.03em;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--color-cream);
}

.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    font-size: 0.88rem;
    font-weight: 600;
    color: var(--color-navy);
    margin-bottom: 6px;
    letter-spacing: 0.03em;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    font-family: var(--font-body);
    letter-spacing: 0.02em;
    transition: all var(--transition-fast);
    background: var(--color-cream);
    color: var(--color-navy);
    resize: vertical;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-teal);
    box-shadow: 0 0 0 3px rgba(0, 136, 145, 0.08);
    background: var(--color-white);
}

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

.form-submit-btn {
    width: 100%;
    padding: 14px 28px;
    background: var(--color-teal);
    color: #ffffff;
    border: none;
    border-radius: 40px;
    font-size: 1rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    cursor: pointer;
    transition: all var(--transition-smooth);
    box-shadow: 0 6px 20px rgba(0, 136, 145, 0.3);
}

.form-submit-btn:hover {
    background: var(--color-deep-teal);
    box-shadow: 0 10px 28px rgba(0, 136, 145, 0.4);
    transform: translateY(-2px);
}

/* ============ 底部导航 - 100%宽度 ============ */
.site-footer {
    width: 100%;
    background: var(--color-navy);
    color: rgba(255, 255, 255, 0.85);
    padding: 56px 24px 32px;
    position: relative;
}

.site-footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--color-teal), var(--color-deep-teal), var(--color-teal));
}

.footer-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.2fr;
    gap: 36px;
}

.footer-col h4 {
    font-family: var(--font-heading);
    font-size: 1.05rem;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 16px;
    letter-spacing: 0.04em;
}

.footer-col p,
.footer-col a {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.8;
    letter-spacing: 0.02em;
    text-decoration: none;
    display: block;
    transition: color var(--transition-fast);
}

.footer-col a:hover {
    color: var(--color-teal);
}

.footer-bottom {
    max-width: var(--max-width);
    margin: 32px auto 0;
    padding-top: 24px;
    border-top: 1px solid rgba(255, 255, 255, 0.12);
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    justify-content: space-between;
    align-items: center;
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.5);
    letter-spacing: 0.03em;
}

.footer-bottom a {
    color: rgba(255, 255, 255, 0.6);
    text-decoration: none;
    transition: color var(--transition-fast);
    font-weight: 500;
}

.footer-bottom a:hover {
    color: var(--color-teal);
}

.mobile-version-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 18px;
    background: rgba(255, 255, 255, 0.06);
    border-radius: 24px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: all var(--transition-fast);
    font-weight: 500;
}

.mobile-version-link:hover {
    background: rgba(255, 255, 255, 0.12);
    border-color: var(--color-teal);
    color: var(--color-teal) !important;
}

/* ============ 响应式设计 ============ */
@media (max-width: 1024px) {
    .research-cards {
        grid-template-columns: repeat(2, 1fr);
    }
    .news-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .stats-row {
        grid-template-columns: repeat(2, 1fr);
    }
    .about-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }
    .about-image {
        max-width: 500px;
        margin: 0 auto;
    }
    .contact-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }
    .footer-inner {
        grid-template-columns: 1fr 1fr;
        gap: 28px;
    }
    .hero-content h1 {
        font-size: 2.4rem;
    }
    .section-title {
        font-size: 1.8rem;
    }
}

@media (max-width: 768px) {
    .site-header {
        height: var(--nav-height-mobile);
    }
    .header-inner {
        padding: 0 16px;
    }
    .logo-icon {
        width: 36px;
        height: 36px;
        font-size: 1.1rem;
    }
    .logo-text {
        font-size: 1rem;
    }
    .main-nav {
        display: none;
    }
    .menu-toggle {
        display: flex;
    }
    .mobile-nav-panel {
        display: flex;
    }

    .hero-section {
        margin-top: var(--nav-height-mobile);
        min-height: 440px;
        padding: 40px 16px;
    }
    .hero-content h1 {
        font-size: 1.8rem;
        letter-spacing: 0.03em;
    }
    .hero-content .hero-subtitle {
        font-size: 0.95rem;
    }
    .hero-buttons {
        flex-direction: column;
        align-items: center;
        gap: 10px;
    }
    .btn {
        width: 100%;
        max-width: 300px;
        justify-content: center;
        padding: 12px 24px;
        font-size: 0.9rem;
    }
    .hero-img-wrapper {
        margin-top: 24px;
        border-radius: var(--radius-md);
    }

    .section {
        padding: 48px 16px;
    }
    .section-title {
        font-size: 1.5rem;
    }
    .section-desc {
        font-size: 0.9rem;
    }

    .research-cards {
        grid-template-columns: 1fr;
        gap: 14px;
    }
    .news-grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }
    .stats-row {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }
    .stat-number {
        font-size: 2rem;
    }
    .stat-label {
        font-size: 0.8rem;
    }

    .about-features {
        grid-template-columns: 1fr;
        gap: 8px;
    }
    .brand-scroll {
        gap: 14px;
    }
    .brand-item {
        min-width: 100px;
        padding: 16px 18px;
    }
    .brand-item img {
        height: 32px;
        max-width: 100px;
    }

    .contact-grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }
    .contact-info-card,
    .contact-form-card {
        padding: 22px 16px;
    }

    .footer-inner {
        grid-template-columns: 1fr;
        gap: 22px;
        text-align: center;
    }
    .footer-bottom {
        flex-direction: column;
        text-align: center;
        gap: 10px;
    }
    .site-footer {
        padding: 40px 16px 24px;
    }

    .about-image {
        max-width: 100%;
    }
    .highlight-box {
        padding: 14px 16px;
        font-size: 0.9rem;
    }
}

@media (max-width: 480px) {
    .hero-content h1 {
        font-size: 1.5rem;
    }
    .hero-badge {
        font-size: 0.75rem;
        padding: 6px 14px;
    }
    .stats-row {
        grid-template-columns: 1fr 1fr;
        gap: 8px;
    }
    .stat-item {
        padding: 20px 12px;
    }
    .stat-number {
        font-size: 1.6rem;
    }
    .section-title {
        font-size: 1.3rem;
    }
    .btn {
        font-size: 0.85rem;
        padding: 10px 20px;
    }
}