/* 企业级高大上设计风格 - CSS变量定义 */
:root {
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --accent-color: #4facfe;
    --dark-bg: #1a1a2e;
    --darker-bg: #16213e;
    --light-bg: #ffffff;
    --card-bg: #ffffff;
    --text-primary: #1a1a2e;
    --text-secondary: #6c757d;
    --border-color: #e0e0e0;
    --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 12px 36px rgba(0, 0, 0, 0.15);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 全局样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    background-color: var(--light-bg);
    background-image: radial-gradient(circle at 10% 20%, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 90%);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    overflow-x: hidden;
}

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

/* 导航栏样式 */
header {
    background: var(--dark-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    box-shadow: var(--shadow-md);
    padding: 1.2rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
}

header.scrolled {
    padding: 0.8rem 0;
    box-shadow: var(--shadow-lg);
}

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

.logo h1 {
    font-size: 2rem;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.5px;
}

nav ul {
    display: flex;
    list-style: none;
    gap: 2.5rem;
}

nav ul li a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    padding: 0.5rem 0;
    position: relative;
}

nav ul li a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-color);
    transition: var(--transition);
}

nav ul li a:hover,
nav ul li a.active {
    color: #ffffff;
}

nav ul li a:hover::after,
nav ul li a.active::after {
    width: 100%;
}

/* 横幅区域样式 */
.banner {
    background: var(--dark-bg);
    color: #ffffff;
    padding: 6rem 0;
    position: relative;
    overflow: hidden;
}

.banner::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(circle at 20% 30%, rgba(102, 126, 234, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(118, 75, 162, 0.1) 0%, transparent 50%);
    animation: gradientShift 15s ease infinite;
}

@keyframes gradientShift {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(10px, 10px); }
}

.banner::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="60" height="60" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grid" width="60" height="60" patternUnits="userSpaceOnUse"><path d="M 60 0 L 0 0 0 60" fill="none" stroke="rgba(255,255,255,0.03)" stroke-width="1"/></pattern></defs><rect width="60" height="60" fill="url(%23grid)"/></svg>');
}

.banner .container {
    position: relative;
    z-index: 2;
    text-align: center;
}

.banner h2 {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    line-height: 1.2;
    letter-spacing: -1px;
    opacity: 0;
    animation: fadeUp 0.8s ease forwards 0.2s;
}

.banner p {
    font-size: 1.3rem;
    margin-bottom: 3rem;
    opacity: 0.9;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
    opacity: 0;
    animation: fadeUp 0.8s ease forwards 0.4s;
}

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

/* 强调文本 */
.highlight-text {
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 700;
}

.cta-buttons {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* 按钮样式 */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2.5rem;
    border-radius: 50px;
    font-weight: 600;
    text-decoration: none;
    text-transform: none;
    letter-spacing: 0.5px;
    font-size: 1.1rem;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    position: relative;
    overflow: hidden;
    opacity: 0;
    animation: fadeUp 0.8s ease forwards 0.6s;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: var(--transition);
}

.btn:hover::before {
    left: 100%;
}

.btn-primary {
    background: var(--primary-gradient);
    color: white;
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 35px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.3);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.5);
    transform: translateY(-3px);
}

/* 主要内容区域样式 */
main {
    padding: 4rem 0;
}

section {
    margin-bottom: 5rem;
}

/* 服务介绍卡片 */
.service-card {
    background: var(--card-bg);
    border-radius: 16px;
    box-shadow: var(--shadow-md);
    padding: 2.5rem;
    margin-bottom: 2rem;
    transition: var(--transition);
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: var(--primary-gradient);
    transform: scaleX(0);
    transition: var(--transition);
}

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

.service-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

/* 标题样式 */
h2 {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 2rem;
    text-align: center;
    letter-spacing: -0.5px;
    position: relative;
    padding-bottom: 1rem;
}

h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: var(--primary-gradient);
    border-radius: 2px;
}

h3 {
    font-size: 1.8rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    letter-spacing: -0.3px;
}

h4 {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1rem;
    letter-spacing: -0.2px;
}

/* 服务特点 */
.service-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
}

.feature-box {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.feature-box::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: var(--primary-gradient);
}

.feature-box:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
    border-color: rgba(102, 126, 234, 0.3);
}

.feature-box h4 {
    margin-top: 0;
    color: var(--text-primary);
    font-size: 1.25rem;
    margin-bottom: 1rem;
}

.feature-box p {
    color: var(--text-secondary);
    margin-bottom: 0;
    line-height: 1.7;
}

/* 价格卡片 */
.price-card {
    background: var(--primary-gradient);
    color: white;
    border-radius: 20px;
    padding: 3rem;
    text-align: center;
    box-shadow: 0 15px 40px rgba(102, 126, 234, 0.3);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.price-card::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
    animation: pulse 4s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
        opacity: 0.5;
    }
    50% {
        transform: scale(1.2);
        opacity: 0.8;
    }
}

.price-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 50px rgba(102, 126, 234, 0.4);
}

.price-card h3 {
    color: white;
    margin-bottom: 2rem;
    font-size: 2rem;
}

.price {
    font-size: 5rem;
    font-weight: 800;
    margin-bottom: 0.5rem;
    letter-spacing: -2px;
    position: relative;
    z-index: 1;
}

.price-period {
    font-size: 1.3rem;
    margin-bottom: 2.5rem;
    opacity: 0.9;
    position: relative;
    z-index: 1;
}

/* 优势列表 */
.advantage-list {
    list-style: none;
    margin: 0;
    padding: 0;
}

.advantage-list li {
    padding: 1rem 0;
    padding-left: 2.5rem;
    position: relative;
    line-height: 1.7;
    color: var(--text-secondary);
    transition: var(--transition);
}

.advantage-list li::before {
    content: '✓';
    position: absolute;
    left: 0;
    top: 1rem;
    color: var(--accent-color);
    font-weight: bold;
    font-size: 1.3rem;
    background: rgba(79, 172, 254, 0.1);
    width: 28px;
    height: 28px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.9rem;
}

.advantage-list li:hover {
    color: var(--text-primary);
    transform: translateX(5px);
}

/* 代理类型卡片样式 */
.proxy-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
    margin-top: 2.5rem;
}

.proxy-item {
    background: white;
    padding: 2.5rem;
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
    transition: all 0.4s ease;
    border: 1px solid transparent;
    text-align: center;
}

.proxy-item:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 48px rgba(0, 0, 0, 0.12);
    border-color: #667eea;
}

.proxy-item h4 {
    color: #667eea;
    margin-top: 0;
    margin-bottom: 1.2rem;
}

.proxy-item p {
    color: #555;
    line-height: 1.7;
    margin-bottom: 1.5rem;
}

.proxy-item .btn {
    margin-top: 0.5rem;
}

/* 关于页面样式 */
.about-content {
    background: white;
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
    padding: 2.5rem;
}

.about-content p {
    margin-bottom: 1.2rem;
    line-height: 1.8;
    color: #555;
}

.about-content ul,
.about-content ol {
    margin-left: 2rem;
    margin-bottom: 1.8rem;
}

.about-content li {
    margin-bottom: 0.8rem;
    line-height: 1.8;
    color: #555;
}

.proxy-types-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.proxy-type-item {
    background: linear-gradient(135deg, #f0f4f8, #e9ecef);
    padding: 1.5rem;
    border-radius: 8px;
    border-left: 4px solid #667eea;
    transition: all 0.3s ease;
}

.proxy-type-item:hover {
    transform: translateX(10px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.2);
}

.proxy-type-item h4 {
    margin-top: 0;
    color: #667eea;
}

.proxy-type-item p {
    margin-bottom: 0;
}

/* 代理配置页面样式 */
.device-config {
    background: white;
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
    padding: 2.5rem;
    margin-bottom: 2.5rem;
}

.config-steps {
    margin: 2.5rem 0;
}

.step {
    display: flex;
    margin-bottom: 2.5rem;
    align-items: flex-start;
}

.step-number {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    width: 3.5rem;
    height: 3.5rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 1.3rem;
    margin-right: 1.5rem;
    flex-shrink: 0;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
}

.step-content {
    flex: 1;
    background: linear-gradient(135deg, #f8f9ff, #f0f4f8);
    padding: 1.5rem;
    border-radius: 10px;
    border-left: 4px solid #667eea;
}

.step-content h4 {
    color: #764ba2;
    margin-top: 0;
    margin-bottom: 0.8rem;
}

.step-content p {
    margin-bottom: 1rem;
    color: #555;
}

.step-content ul {
    margin-left: 1.5rem;
    margin-bottom: 1rem;
}

.step-content li {
    margin-bottom: 0.5rem;
    color: #555;
}

/* 协议介绍样式 */
.protocols {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.protocol-item {
    background: linear-gradient(135deg, #f0f4f8, #e9ecef);
    padding: 1.5rem;
    border-radius: 8px;
    border-top: 4px solid #667eea;
    text-align: center;
    transition: all 0.3s ease;
}

.protocol-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.2);
}

.protocol-item h4 {
    margin-top: 0;
    color: #667eea;
}

/* 代理提示样式 */
.proxy-tips {
    background: linear-gradient(135deg, #f0f4f8, #e9ecef);
    padding: 2rem;
    border-radius: 12px;
    border-left: 4px solid #667eea;
    margin: 2rem 0;
}

.proxy-tips h3 {
    color: #667eea;
    margin-top: 0;
}

.proxy-tips ul {
    margin-left: 1.5rem;
}

.proxy-tips li {
    margin-bottom: 0.8rem;
    line-height: 1.6;
    color: #555;
}

/* 示例代码样式 */
.proxy-example {
    background: white;
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
    padding: 2rem;
    margin: 2rem 0;
}

.proxy-example h3 {
    color: #667eea;
    margin-top: 0;
    margin-bottom: 1.5rem;
}

.example-code {
    background: linear-gradient(135deg, #2d3748, #4a5568);
    color: #e2e8f0;
    padding: 2rem;
    border-radius: 8px;
    font-family: 'Courier New', Courier, monospace;
    margin: 1rem 0;
    box-shadow: 0 4px 15px rgba(45, 55, 72, 0.3);
}

.example-code p {
    margin: 0.5rem 0;
    color: #e2e8f0;
}

.examples {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin: 1.5rem 0;
}

.example-item h4 {
    margin-top: 0;
    color: #764ba2;
}

/* 联系页面样式 */
.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-top: 2rem;
}

.contact-info {
    background: white;
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
    padding: 2.5rem;
}

.info-items {
    margin: 1.5rem 0;
}

.info-item {
    margin-bottom: 2rem;
}

.info-item h4 {
    color: #764ba2;
    margin-bottom: 0.8rem;
}

.info-item a {
    color: #667eea;
    text-decoration: none;
    transition: color 0.3s ease;
}

.info-item a:hover {
    color: #764ba2;
    text-decoration: underline;
}

.social-links {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.social-link {
    display: inline-block;
    padding: 0.8rem 1.5rem;
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    text-decoration: none;
    border-radius: 8px;
    transition: all 0.3s ease;
    font-weight: 600;
}

.social-link:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
}

/* 表单样式 */
.contact-form {
    background: white;
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
    padding: 2.5rem;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #555;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 1rem;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 1rem;
    transition: all 0.3s ease;
    font-family: inherit;
    color: #555;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

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

.success-message {
    background: linear-gradient(135deg, #d4edda, #c3e6cb);
    color: #155724;
    padding: 1.5rem;
    border-radius: 8px;
    margin-top: 1.5rem;
    border-left: 4px solid #28a745;
}

/* 统计数据样式 */
.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
}

.stat-item {
    text-align: center;
    padding: 2rem;
    background: white;
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
}

.stat-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 48px rgba(0, 0, 0, 0.12);
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: #667eea;
    margin-bottom: 0.5rem;
}

.stat-label {
    color: #6c757d;
    font-size: 1.1rem;
    font-weight: 600;
}

/* SOCKS5 优势样式 */
.socks5-highlight {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 3rem 0;
    border-radius: 12px;
    margin: 2rem 0;
    position: relative;
    overflow: hidden;
}

.socks5-highlight::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"><defs><pattern id="grid" width="100" height="100" patternUnits="userSpaceOnUse"><path d="M 100 0 L 0 0 0 100" fill="none" stroke="rgba(255,255,255,0.1)" stroke-width="1"/></pattern></defs><rect width="100" height="100" fill="url(%23grid)"/></svg>');
    opacity: 0.3;
}

.socks5-highlight .container {
    position: relative;
    z-index: 1;
}

.socks5-highlight h3 {
    color: white;
    font-size: 2rem;
    margin-bottom: 1.5rem;
}

.socks5-highlight p {
    text-align: center;
    font-size: 1.1rem;
    max-width: 800px;
    margin: 0 auto;
    opacity: 0.95;
}

.socks5-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.socks5-feature {
    background: rgba(255, 255, 255, 0.1);
    padding: 1.5rem;
    border-radius: 8px;
    border-left: 4px solid rgba(255, 255, 255, 0.3);
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
}

.socks5-feature:hover {
    transform: translateX(10px);
    background: rgba(255, 255, 255, 0.15);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

.socks5-feature h4 {
    margin-top: 0;
    color: white;
}

.socks5-feature p {
    margin-bottom: 0;
    text-align: left;
    max-width: 100%;
}

/* 比较表格样式 */
.comparison-table {
    width: 100%;
    border-collapse: collapse;
    margin: 2rem 0;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
    border-radius: 12px;
    overflow: hidden;
}

.comparison-table th,
.comparison-table td {
    padding: 1.2rem;
    text-align: left;
    border-bottom: 1px solid #e9ecef;
}

.comparison-table th {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    font-weight: 700;
}

.comparison-table tr:hover {
    background-color: #f8f9ff;
}

.comparison-table tr:last-child td {
    border-bottom: none;
}

/* 统计数据 */
.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 2rem;
    margin: 4rem 0;
}

.stat-item {
    text-align: center;
    padding: 2.5rem 1rem;
    background: var(--card-bg);
    border-radius: 16px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.stat-item:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.stat-number {
    font-size: 3.5rem;
    font-weight: 800;
    color: var(--accent-color);
    margin-bottom: 0.5rem;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 1.1rem;
    font-weight: 500;
    color: var(--text-secondary);
}

/* 流程步骤 */
.steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
}

.step-item {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: 16px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    transition: var(--transition);
    position: relative;
}

.step-item:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.step-number {
    position: absolute;
    top: -15px;
    left: 2rem;
    width: 40px;
    height: 40px;
    background: var(--primary-gradient);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    box-shadow: var(--shadow-md);
}

.step-item h4 {
    margin-top: 1rem;
    margin-bottom: 1rem;
}

/* 页脚 */
footer {
    background: var(--dark-bg);
    color: rgba(255, 255, 255, 0.8);
    padding: 4rem 0 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    position: relative;
}

footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--primary-gradient), transparent);
}

footer .container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-info h3 {
    color: white;
    margin-bottom: 1.5rem;
    font-size: 1.5rem;
}

.footer-links {
    list-style: none;
    padding: 0;
}

.footer-links li {
    margin-bottom: 1rem;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.6);
    text-decoration: none;
    transition: var(--transition);
}

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

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.5);
}

/* 滚动动画 */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: var(--transition);
}

.animate-on-scroll.animated {
    opacity: 1;
    transform: translateY(0);
}

/* 响应式设计 - 三端自适应 */
/* 平板设备 */
@media (max-width: 992px) {
    .container {
        max-width: 900px;
    }
    
    .features-grid,
    .proxy-grid {
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    }
    
    .contact-content {
        grid-template-columns: 1fr;
    }
}

/* 大屏手机设备 */
@media (max-width: 768px) {
    .container {
        max-width: 700px;
        padding: 0 20px;
    }
    
    header .container {
        flex-direction: column;
        gap: 1rem;
        padding: 1rem 20px;
    }
    
    nav ul {
        flex-wrap: wrap;
        justify-content: center;
        padding: 0;
    }
    
    nav ul li {
        margin: 0 1rem;
        margin-bottom: 0.5rem;
    }
    
    .banner {
        padding: 4rem 0;
    }
    
    .banner h2 {
        font-size: 2rem;
    }
    
    .banner p {
        font-size: 1.1rem;
    }
    
    .cta-buttons {
        flex-direction: column;
        align-items: center;
        gap: 1.5rem;
    }
    
    section h2 {
        font-size: 1.8rem;
    }
    
    section h3 {
        font-size: 1.5rem;
    }
    
    .step {
        flex-direction: column;
    }
    
    .step-number {
        margin-bottom: 1rem;
    }
    
    .features-grid,
    .proxy-grid,
    .proxy-types-list,
    .protocols,
    .examples,
    .stats,
    .socks5-features {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .about-content,
    .device-config,
    .contact-info,
    .contact-form {
        padding: 1.5rem;
    }
    
    .stat-item {
        padding: 1.5rem;
    }
    
    .stat-number {
        font-size: 2rem;
    }
    
    /* 优化移动端按钮样式 */
    .btn {
        width: 100%;
        max-width: 300px;
        text-align: center;
    }
    
    /* 优化移动端价格展示 */
    .socks5-highlight {
        padding: 2rem 0;
    }
    
    /* 优化移动端配置步骤 */
    .step-content {
        padding: 1.2rem;
    }
}

/* 小屏手机设备 */
@media (max-width: 480px) {
    .container {
        max-width: 100%;
        padding: 0 15px;
    }
    
    header .container {
        padding: 1rem 15px;
    }
    
    .logo h1 {
        font-size: 1.8rem;
        text-align: center;
    }
    
    nav ul li {
        margin: 0 0.5rem;
    }
    
    .banner {
        padding: 3rem 0;
    }
    
    .banner h2 {
        font-size: 1.6rem;
    }
    
    .banner p {
        font-size: 1rem;
    }
    
    main {
        padding: 2rem 0;
    }
    
    section {
        margin-bottom: 2.5rem;
    }
    
    section h2 {
        font-size: 1.6rem;
    }
    
    section h3 {
        font-size: 1.3rem;
    }
    
    .about-content,
    .device-config,
    .contact-info,
    .contact-form {
        padding: 1.2rem;
        border-radius: 8px;
    }
    
    .step-number {
        width: 3rem;
        height: 3rem;
        font-size: 1.1rem;
    }
    
    .step-content {
        padding: 1rem;
    }
    
    .btn {
        padding: 0.8rem 1.5rem;
        font-size: 0.9rem;
        width: 100%;
        max-width: 100%;
    }
    
    /* 优化移动端价格展示 */
    .stat-item {
        padding: 1.2rem;
    }
    
    .stat-number {
        font-size: 1.8rem;
    }
    
    .stat-label {
        font-size: 1rem;
    }
    
    /* 优化移动端购买按钮 */
    .socks5-highlight .btn {
        font-size: 1rem;
        padding: 1rem 2rem;
    }
    
    /* 优化移动端表单 */
    .form-group input,
    .form-group textarea {
        padding: 0.8rem;
        font-size: 0.9rem;
    }
    
    /* 优化移动端代码示例 */
    .example-code {
        padding: 1rem;
        font-size: 0.9rem;
    }
}

/* 超大屏设备优化 */
@media (min-width: 1200px) {
    .container {
        max-width: 1200px;
    }
    
    .features-grid,
    .proxy-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .stats {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .socks5-features {
        grid-template-columns: repeat(3, 1fr);
    }
}