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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Navigation */
.navbar {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.nav-brand .brand-link {
    text-decoration: none;
    color: inherit;
}

.nav-brand .brand-link:hover {
    text-decoration: none;
}

.nav-brand h2 {
    color: #2563eb;
    font-weight: 700;
    transition: color 0.2s ease;
}

.nav-brand .brand-link:hover h2 {
    color: #1d4ed8;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
    align-items: center;
}

.nav-menu li {
    display: flex;
    align-items: center;
}

.nav-menu a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    line-height: 1.5;
    padding: 0.5rem 0;
    transition: color 0.3s;
}

.nav-menu a:hover {
    color: #2563eb;
}

/* Language Selector */
.language-selector {
    position: relative;
}

.lang-dropdown {
    position: relative;
    display: inline-block;
}

.lang-button {
    background: none;
    border: 1px solid #e5e7eb;
    color: #333;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    line-height: 1.5;
    vertical-align: middle;
    transition: all 0.2s ease;
}

.lang-button:hover {
    background-color: #f9fafb;
    border-color: #2563eb;
    color: #2563eb;
}

.lang-options {
    position: absolute;
    top: 100%;
    right: 0;
    background: white;
    border: 1px solid #e5e7eb;
    border-radius: 4px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    min-width: 120px;
    display: none;
}

.lang-options.show {
    display: block;
}

.lang-option {
    display: block;
    padding: 0.5rem 1rem;
    color: #333;
    text-decoration: none;
    border-bottom: 1px solid #f3f4f6;
}

.lang-option:last-child {
    border-bottom: none;
}

.lang-option:hover {
    background-color: #f9fafb;
    color: #2563eb;
}

.lang-option.active {
    background-color: #2563eb;
    color: white;
}

.lang-option.active:hover {
    background-color: #1d4ed8;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 120px 0 80px;
    text-align: center;
}

.hero-content h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: #2563eb;
    color: white;
}

.btn-primary:hover {
    background: #1d4ed8;
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid white;
}

.btn-secondary:hover {
    background: white;
    color: #2563eb;
}

/* Features Section */
.features {
    padding: 80px 0;
    background: #f8fafc;
}

.features h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #1e293b;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    transition: transform 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #1e293b;
}

/* Page Header */
.page-header {
    background: #1e293b;
    color: white;
    padding: 120px 0 60px;
    text-align: center;
}

.page-header h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

/* Content Sections */
.about-content, .services-content, .contact-content {
    padding: 60px 0;
}

.about-section {
    margin-bottom: 3rem;
}

.about-section h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: #1e293b;
}

.values-list {
    list-style: none;
}

.values-list li {
    padding: 0.5rem 0;
    border-bottom: 1px solid #e2e8f0;
}

/* Services Grid */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.service-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    border-left: 4px solid #2563eb;
}

.service-card h3 {
    color: #1e293b;
    margin-bottom: 1rem;
}

.service-card ul {
    list-style: none;
    margin-top: 1rem;
}

.service-card li {
    padding: 0.25rem 0;
    color: #64748b;
}

.service-card li:before {
    content: "✓ ";
    color: #2563eb;
    font-weight: bold;
}

/* Contact */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
}

.contact-item {
    margin-bottom: 1.5rem;
}

.contact-item strong {
    color: #1e293b;
}

/* Forms */
.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #1e293b;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 1px solid #d1d5db;
    border-radius: 6px;
    font-size: 1rem;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #2563eb;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

/* 人机验证样式 */
.captcha-group {
    background: #f8fafc;
    padding: 1rem;
    border-radius: 8px;
    border: 1px solid #e2e8f0;
    margin: 1.5rem 0;
}

.captcha-container {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-top: 0.5rem;
}

.captcha-question {
    font-size: 1.1rem;
    font-weight: 600;
    color: #1e293b;
    background: #fff;
    padding: 8px 12px;
    border-radius: 4px;
    border: 1px solid #d1d5db;
    min-width: 120px;
    text-align: center;
}

.captcha-group input[type="number"] {
    max-width: 120px;
    text-align: center;
    font-weight: 600;
    padding: 10px 8px;
}

.captcha-group input[type="number"]::placeholder {
    color: #9ca3af;
    font-weight: normal;
    font-size: 0.9rem;
}

.captcha-help {
    color: #64748b;
    font-size: 0.875rem;
    margin-top: 0.5rem;
    display: block;
}

/* Alert Messages */
.alert {
    padding: 12px 16px;
    margin-bottom: 1rem;
    border: 1px solid transparent;
    border-radius: 6px;
    font-size: 0.875rem;
}

.alert-success {
    color: #065f46;
    background-color: #d1fae5;
    border-color: #a7f3d0;
}

.alert-error {
    color: #991b1b;
    background-color: #fee2e2;
    border-color: #fecaca;
}

.alert-warning {
    color: #92400e;
    background-color: #fef3c7;
    border-color: #fde68a;
}

/* Footer */
.footer {
    background: #1e293b;
    color: white;
    padding: 2rem 0;
    margin-top: auto;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-copyright {
    margin: 0;
}

.footer-beian {
    margin: 0;
    font-size: inherit;
}

.footer-beian a {
    color: inherit;
    text-decoration: none;
    transition: opacity 0.3s;
}

.footer-beian a:hover {
    opacity: 0.8;
    text-decoration: underline;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .lang-button {
        padding: 0.4rem 0.8rem;
        font-size: 0.85rem;
    }
    
    .lang-options {
        min-width: 100px;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .footer-content {
        flex-direction: column;
        gap: 0.5rem;
        text-align: center;
    }
}