/* ============================================
   鲁工自动化 企业官网样式
   风格：科技蓝 + 金属质感
   ============================================ */

/* --- 基础变量 --- */
:root {
    --blue-900: #0a1628;
    --blue-800: #0d2137;
    --blue-700: #102a4a;
    --blue-600: #1a3a5c;
    --blue-500: #1e5080;
    --blue-400: #2a6aaa;
    --accent: #4da6ff;
    --accent-light: #7ec4ff;
    --accent-glow: rgba(77, 166, 255, 0.25);
    --metal: #c0cfe0;
    --metal-dark: #8a9bb5;
    --white: #ffffff;
    --gray-100: #f0f4f8;
    --gray-200: #e2e8f0;
    --gray-600: #4a5568;
    --gray-800: #1a202c;
    --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.12);
    --shadow-hover: 0 12px 40px rgba(77, 166, 255, 0.15);
    --radius: 12px;
}

/* --- Reset & Base --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
    scroll-behavior: smooth;
    scroll-padding-top: 72px;
    font-size: 16px;
}

body {
    font-family: var(--font-stack);
    color: var(--gray-800);
    background: var(--white);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* --- 导航栏 --- */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 16px 0;
    transition: var(--transition);
    background: transparent;
}

.navbar.scrolled {
    background: rgba(10, 22, 40, 0.95);
    backdrop-filter: blur(16px);
    padding: 10px 0;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--white);
    letter-spacing: 1px;
}

.logo-text { display: flex; align-items: baseline; }

.nav-links {
    display: flex;
    list-style: none;
    gap: 32px;
}

.nav-links a {
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.9rem;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
    padding: 4px 0;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: var(--transition);
    border-radius: 1px;
}

.nav-links a:hover { color: var(--white); }
.nav-links a:hover::after { width: 100%; }

.nav-actions { display: flex; align-items: center; gap: 12px; }

.staff-login-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 16px;
    background: rgba(77, 166, 255, 0.15);
    border: 1px solid rgba(77, 166, 255, 0.4);
    border-radius: 6px;
    color: var(--accent-light);
    font-size: 0.82rem;
    font-weight: 600;
    transition: var(--transition);
    text-decoration: none;
}

.staff-login-btn:hover {
    background: var(--accent);
    color: var(--white);
    border-color: var(--accent);
}

.staff-login-btn svg { flex-shrink: 0; }

.lang-toggle {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: var(--white);
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    letter-spacing: 1px;
}

.lang-toggle:hover {
    background: var(--accent);
    border-color: var(--accent);
}

/* 移动端菜单按钮 */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.mobile-menu-btn span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--white);
    border-radius: 1px;
    transition: var(--transition);
}

.mobile-menu-btn.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.mobile-menu-btn.active span:nth-child(2) { opacity: 0; }
.mobile-menu-btn.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* --- Hero 首屏 --- */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(160deg, var(--blue-900) 0%, var(--blue-700) 40%, var(--blue-600) 100%);
    overflow: hidden;
}

#particleCanvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    padding: 0 24px;
    max-width: 800px;
}

.hero-badge {
    display: inline-block;
    padding: 6px 20px;
    background: rgba(77, 166, 255, 0.15);
    border: 1px solid rgba(77, 166, 255, 0.3);
    border-radius: 30px;
    color: var(--accent-light);
    font-size: 0.85rem;
    font-weight: 500;
    margin-bottom: 24px;
    letter-spacing: 2px;
}

.hero-title {
    font-size: clamp(2.2rem, 5vw, 3.8rem);
    font-weight: 800;
    color: var(--white);
    line-height: 1.2;
    margin-bottom: 20px;
    letter-spacing: -0.5px;
}

.hero-title-accent {
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-light) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-desc {
    font-size: 1.05rem;
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.8;
    margin-bottom: 36px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

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

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 32px;
    border-radius: 8px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    letter-spacing: 0.5px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent) 0%, #3b8fd4 100%);
    color: var(--white);
    box-shadow: 0 4px 16px rgba(77, 166, 255, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(77, 166, 255, 0.4);
}

.btn-outline {
    background: transparent;
    color: var(--white);
    border: 1.5px solid rgba(255, 255, 255, 0.4);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--white);
    transform: translateY(-2px);
}

.btn-full { width: 100%; }

.hero-scroll-hint {
    position: absolute;
    bottom: 32px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 2;
}

.scroll-arrow {
    width: 24px;
    height: 24px;
    border-right: 2px solid rgba(255, 255, 255, 0.4);
    border-bottom: 2px solid rgba(255, 255, 255, 0.4);
    transform: rotate(45deg);
    animation: scrollBounce 2s ease-in-out infinite;
}

@keyframes scrollBounce {
    0%, 100% { transform: rotate(45deg) translate(0, 0); opacity: 0.4; }
    50% { transform: rotate(45deg) translate(4px, 4px); opacity: 1; }
}

/* --- 通用板块样式 --- */
.section {
    padding: 100px 0;
}

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

.section-tag {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 3px;
    color: var(--accent);
    margin-bottom: 12px;
}

.section-title {
    font-size: clamp(1.8rem, 3vw, 2.5rem);
    font-weight: 800;
    color: var(--blue-900);
    margin-bottom: 16px;
}

.section-subtitle {
    font-size: 1rem;
    color: var(--gray-600);
    max-width: 520px;
    margin: 0 auto;
}

/* --- 关于我们 --- */
.about {
    background: var(--white);
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: start;
}

.about-text p {
    color: var(--gray-600);
    margin-bottom: 16px;
    font-size: 0.95rem;
    line-height: 1.9;
}

.about-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.stat-item {
    background: linear-gradient(135deg, var(--blue-800), var(--blue-700));
    padding: 28px 20px;
    border-radius: var(--radius);
    text-align: center;
    color: var(--white);
    position: relative;
    overflow: hidden;
}

.stat-item::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
    pointer-events: none;
}

.stat-number {
    font-size: 2.4rem;
    font-weight: 800;
    color: var(--accent-light);
    display: inline;
    line-height: 1;
}

.stat-suffix {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--accent);
    display: inline;
}

.stat-label {
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.7);
    margin-top: 6px;
}

.about-certifications {
    display: flex;
    justify-content: center;
    gap: 40px;
    margin-top: 48px;
    padding-top: 40px;
    border-top: 1px solid var(--gray-200);
}

.cert-item {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--blue-700);
}

/* --- 解决方案 --- */
.solutions {
    background: var(--gray-100);
}

.solutions-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.solution-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 36px 32px;
    box-shadow: var(--shadow-card);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.solution-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), var(--accent-light));
    transform: scaleX(0);
    transition: var(--transition);
    transform-origin: left;
}

.solution-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}

.solution-card:hover::before { transform: scaleX(1); }

.solution-icon {
    margin-bottom: 20px;
}

.solution-card h3 {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--blue-900);
    margin-bottom: 12px;
}

.solution-card p {
    font-size: 0.9rem;
    color: var(--gray-600);
    line-height: 1.8;
    margin-bottom: 16px;
}

.solution-link {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--accent);
    transition: var(--transition);
}

.solution-link:hover { color: var(--accent-light); }

/* --- 项目案例 --- */
.cases { background: var(--white); }

.cases-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    grid-template-rows: auto auto;
    gap: 24px;
}

.case-card {
    background: var(--white);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-card);
    transition: var(--transition);
}

.case-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}

.case-card-large {
    grid-row: span 2;
    display: flex;
    flex-direction: column;
}

.case-card-large .case-image {
    flex: 1;
    min-height: 200px;
}

.case-image {
    min-height: 160px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.case-image-placeholder {
    opacity: 0.6;
}

.case-info {
    padding: 24px;
}

.case-tag {
    display: inline-block;
    padding: 3px 12px;
    background: rgba(77, 166, 255, 0.1);
    color: var(--accent);
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: 4px;
    margin-bottom: 10px;
}

.case-info h3 {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--blue-900);
    margin-bottom: 8px;
}

.case-info p {
    font-size: 0.88rem;
    color: var(--gray-600);
    line-height: 1.8;
}

/* --- 新闻动态 --- */
.news { background: var(--gray-100); }

.news-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.news-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 28px;
    box-shadow: var(--shadow-card);
    transition: var(--transition);
    display: flex;
    gap: 20px;
}

.news-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}

.news-date {
    flex-shrink: 0;
    text-align: center;
    min-width: 56px;
}

.news-day {
    display: block;
    font-size: 1.8rem;
    font-weight: 800;
    color: var(--accent);
    line-height: 1;
}

.news-month {
    display: block;
    font-size: 0.75rem;
    color: var(--gray-600);
    margin-top: 4px;
}

.news-content h3 {
    font-size: 0.95rem;
    font-weight: 700;
    color: var(--blue-900);
    margin-bottom: 8px;
    line-height: 1.5;
}

.news-content p {
    font-size: 0.85rem;
    color: var(--gray-600);
    line-height: 1.7;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* --- 联系我们 --- */
.contact { background: var(--white); }

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 48px;
    align-items: start;
}

.contact-item {
    display: flex;
    gap: 16px;
    margin-bottom: 28px;
}

.contact-icon {
    flex-shrink: 0;
    width: 44px;
    height: 44px;
    background: rgba(77, 166, 255, 0.1);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.contact-item h4 {
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--blue-900);
    margin-bottom: 4px;
}

.contact-item p {
    font-size: 0.9rem;
    color: var(--gray-600);
}

/* --- 表单 --- */
.contact-form-wrapper {
    background: var(--gray-100);
    padding: 32px;
    border-radius: var(--radius);
}

.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

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

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 14px 16px;
    background: var(--white);
    border: 1.5px solid var(--gray-200);
    border-radius: 8px;
    font-size: 0.9rem;
    font-family: var(--font-stack);
    color: var(--gray-800);
    transition: var(--transition);
    outline: none;
}

.form-group textarea { resize: vertical; min-height: 100px; }

.form-group input:focus,
.form-group textarea:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

.form-group label {
    position: absolute;
    left: 16px;
    top: 14px;
    font-size: 0.9rem;
    color: var(--gray-600);
    pointer-events: none;
    transition: var(--transition);
    background: var(--white);
    padding: 0 4px;
}

.form-group input:focus + label,
.form-group input:not(:placeholder-shown) + label,
.form-group textarea:focus + label,
.form-group textarea:not(:placeholder-shown) + label {
    top: -8px;
    left: 12px;
    font-size: 0.75rem;
    color: var(--accent);
    font-weight: 600;
}

/* --- 页脚 --- */
.footer {
    background: var(--blue-900);
    color: rgba(255, 255, 255, 0.7);
    padding: 60px 0 0;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr;
    gap: 48px;
    padding-bottom: 40px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--white);
    margin-bottom: 12px;
}

.footer-brand p {
    font-size: 0.88rem;
    line-height: 1.7;
}

.footer-links h4 {
    color: var(--white);
    font-size: 0.9rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.footer-links a {
    display: block;
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.6);
    margin-bottom: 10px;
    transition: var(--transition);
}

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

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding: 20px 0;
    text-align: center;
    font-size: 0.8rem;
}

.footer-bottom .icp-filing {
    margin-top: 8px;
    font-size: 0.75rem;
    color: #718096;
}

.footer-bottom .icp-filing a {
    color: #a0aec0;
    text-decoration: none;
    transition: color 0.2s;
}

.footer-bottom .icp-filing a:hover {
    color: #4da6ff;
}

/* --- 回到顶部 --- */
.back-to-top {
    position: fixed;
    bottom: 24px;
    right: 24px;
    width: 44px;
    height: 44px;
    background: var(--accent);
    color: var(--white);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 12px rgba(77, 166, 255, 0.3);
    opacity: 0;
    visibility: hidden;
    transform: translateY(12px);
    transition: var(--transition);
    z-index: 999;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover { background: var(--accent-light); transform: translateY(-2px); }

/* --- 滚动动画 --- */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* --- 响应式 --- */
@media (max-width: 1024px) {
    .about-grid { grid-template-columns: 1fr; gap: 40px; }
    .solutions-grid { grid-template-columns: 1fr 1fr; }
    .cases-grid { grid-template-columns: 1fr; }
    .case-card-large { grid-row: span 1; }
    .news-grid { grid-template-columns: 1fr 1fr; }
    .contact-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
    .section { padding: 72px 0; }

    .nav-links { display: none; }
    .nav-links.open {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: rgba(10, 22, 40, 0.98);
        padding: 20px 24px;
        gap: 16px;
    }
    .mobile-menu-btn { display: flex; }

    .hero-title { font-size: clamp(1.8rem, 7vw, 2.8rem); }
    .hero-desc { font-size: 0.95rem; }

    .solutions-grid { grid-template-columns: 1fr; }
    .news-grid { grid-template-columns: 1fr; }
    .about-stats { grid-template-columns: 1fr 1fr; }
    .about-certifications { flex-direction: column; align-items: center; gap: 20px; }

    .form-row { grid-template-columns: 1fr; }

    .footer-grid { grid-template-columns: 1fr; gap: 32px; }

    .hero-buttons { flex-direction: column; align-items: center; }
    .btn { width: 100%; max-width: 280px; }
}

@media (max-width: 480px) {
    .about-stats { grid-template-columns: 1fr 1fr; gap: 12px; }
    .stat-item { padding: 20px 12px; }
    .stat-number { font-size: 1.8rem; }
    .news-card { flex-direction: column; gap: 12px; }
    .contact-form-wrapper { padding: 20px; }
}