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

:root {
    /* 暗色主题色彩 */
    --primary-color: #0066cc;
    --primary-hover: #0052a3;
    --secondary-color: #00a6d6;
    --accent-color: #ff6b35;
    
    /* 背景颜色 */
    --bg-primary: #0a0e1a;
    --bg-secondary: #1a1f2e;
    --bg-tertiary: #252b3d;
    --bg-card: #1e2330;
    --bg-modal: rgba(0, 0, 0, 0.8);
    
    /* 文字颜色 */
    --text-primary: #ffffff;
    --text-secondary: #b8c5d6;
    --text-muted: #8a92a5;
    --text-inverse: #1a1f2e;
    
    /* 边框颜色 */
    --border-color: #2d3548;
    --border-hover: #3d4758;
    
    /* 阴影 */
    --shadow-small: 0 2px 4px rgba(0, 0, 0, 0.3);
    --shadow-medium: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-large: 0 8px 24px rgba(0, 0, 0, 0.5);
    
    /* 字体 */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    
    /* 间距 */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-xxl: 48px;
    
    /* 边角 */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
}

body {
    font-family: var(--font-family);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    font-size: 14px;
    overflow-x: hidden;
}

/* 容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* 按钮 */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    border: none;
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.3s ease;
    white-space: nowrap;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--primary-hover), var(--primary-color));
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
}

.btn-outline {
    background: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-outline:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.btn-lg {
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: 16px;
}

.btn-full {
    width: 100%;
    justify-content: center;
}

.btn-user {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

/* 头部导航 */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(26, 31, 46, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid var(--border-color);
}

.navbar {
    padding: var(--spacing-md) 0;
}

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

.nav-brand .logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 20px;
    font-weight: bold;
    color: var(--text-primary);
    text-decoration: none;
}

.nav-brand .logo i {
    font-size: 24px;
    color: var(--primary-color);
}

.nav-menu ul {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
    margin: 0;
}

.nav-menu a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-menu a:hover {
    color: var(--primary-color);
}

.nav-auth {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.dropdown {
    position: relative;
}

.dropdown-content {
    position: absolute;
    top: 100%;
    right: 0;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-large);
    min-width: 180px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.3s ease;
}

.dropdown:hover .dropdown-content {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md);
    color: var(--text-primary);
    text-decoration: none;
    transition: background 0.3s ease;
}

.dropdown-item:hover {
    background: var(--bg-tertiary);
}

.mobile-menu-toggle {
    display: none;
    font-size: 20px;
    cursor: pointer;
    color: var(--text-primary);
}

/* 主要内容 */
.main {
    margin-top: 80px;
}

/* 英雄区域 */
.hero {
    padding: var(--spacing-xxl) 0;
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 20% 80%, rgba(0, 102, 204, 0.1) 0%, transparent 50%),
                radial-gradient(circle at 80% 20%, rgba(0, 166, 214, 0.1) 0%, transparent 50%);
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xxl);
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-title {
    font-size: 48px;
    font-weight: bold;
    line-height: 1.2;
    margin-bottom: var(--spacing-lg);
}

.hero-title .highlight {
    display: block;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-description {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    line-height: 1.6;
}

.hero-actions {
    display: flex;
    gap: var(--spacing-md);
}

.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.cloud-animation {
    position: relative;
    width: 300px;
    height: 300px;
}

.cloud-item {
    position: absolute;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    opacity: 0.8;
    animation: float 6s ease-in-out infinite;
}

.cloud-1 {
    width: 80px;
    height: 80px;
    top: 20px;
    left: 50px;
    animation-delay: 0s;
}

.cloud-2 {
    width: 60px;
    height: 60px;
    top: 100px;
    right: 30px;
    animation-delay: 2s;
}

.cloud-3 {
    width: 100px;
    height: 100px;
    bottom: 30px;
    left: 30px;
    animation-delay: 4s;
}

@keyframes float {
    0%, 100% { transform: translateY(0px) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(180deg); }
}

/* 章节样式 */
section {
    padding: var(--spacing-xxl) 0;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-xxl);
}

.section-title {
    font-size: 36px;
    font-weight: bold;
    margin-bottom: var(--spacing-md);
}

.section-description {
    font-size: 18px;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* 产品网格 */
.products {
    background: var(--bg-secondary);
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

.product-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    transition: all 0.3s ease;
    cursor: pointer;
}

.product-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-large);
    border-color: var(--primary-color);
}

.product-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-md);
    font-size: 24px;
    color: white;
}

.product-title {
    font-size: 20px;
    font-weight: bold;
    margin-bottom: var(--spacing-sm);
}

.product-description {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    line-height: 1.6;
}

.product-specs {
    background: var(--bg-tertiary);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.product-specs h4 {
    margin-bottom: var(--spacing-sm);
    color: var(--primary-color);
}

.product-specs ul {
    list-style: none;
}

.product-specs li {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
}

.product-price {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-md);
}

.price-value {
    font-size: 24px;
    font-weight: bold;
    color: var(--primary-color);
}

.price-unit {
    color: var(--text-muted);
    font-size: 14px;
}

/* 特性网格 */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
}

.feature-card {
    text-align: center;
    padding: var(--spacing-lg);
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
}

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

.feature-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--spacing-md);
    font-size: 32px;
    color: white;
}

.feature-title {
    font-size: 20px;
    font-weight: bold;
    margin-bottom: var(--spacing-sm);
}

.feature-description {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* CTA区域 */
.cta {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
    text-align: center;
}

.cta-title {
    font-size: 32px;
    font-weight: bold;
    margin-bottom: var(--spacing-md);
}

.cta-description {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
}

/* 页脚 */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-xxl) 0 var(--spacing-lg);
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: var(--spacing-xxl);
    margin-bottom: var(--spacing-lg);
}

.footer-brand .logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 20px;
    font-weight: bold;
    color: var(--text-primary);
    text-decoration: none;
    margin-bottom: var(--spacing-md);
}

.footer-brand .logo i {
    font-size: 24px;
    color: var(--primary-color);
}

.footer-brand p {
    color: var(--text-secondary);
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: var(--spacing-lg);
}

.link-group h4 {
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.link-group ul {
    list-style: none;
}

.link-group li {
    margin-bottom: var(--spacing-sm);
}

.link-group a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.3s ease;
}

.link-group a:hover {
    color: var(--primary-color);
}

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
    color: var(--text-muted);
}

/* 模态框 */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--bg-modal);
    z-index: 2000;
    align-items: center;
    justify-content: center;
}

.modal.show {
    display: flex;
}

.modal-content {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    width: 100%;
    max-width: 400px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-large);
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--border-color);
}

.modal-header h3 {
    font-size: 20px;
    font-weight: bold;
}

.close-btn {
    background: none;
    border: none;
    font-size: 24px;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0;
    width: 30px;
    height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-sm);
    transition: all 0.3s ease;
}

.close-btn:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

/* 表单 */
.auth-form {
    padding: var(--spacing-lg);
}

.form-group {
    margin-bottom: var(--spacing-md);
}

.form-group label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-weight: 500;
    color: var(--text-primary);
}

.form-group input {
    width: 100%;
    padding: var(--spacing-md);
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 14px;
    transition: all 0.3s ease;
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(0, 102, 204, 0.2);
}

.input-group {
    display: flex;
    gap: var(--spacing-sm);
}

.input-group input {
    flex: 1;
}

.form-actions {
    margin-bottom: var(--spacing-md);
}

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

.form-footer p {
    color: var(--text-secondary);
}

.form-footer a {
    color: var(--primary-color);
    text-decoration: none;
}

.form-footer a:hover {
    text-decoration: underline;
}

/* 加载提示 */
.loading {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--bg-modal);
    z-index: 3000;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: var(--spacing-md);
}

.loading.show {
    display: flex;
}

.loading-spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--border-color);
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loading p {
    color: var(--text-primary);
    font-size: 16px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: block;
    }
    
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-title {
        font-size: 32px;
    }
    
    .hero-actions {
        justify-content: center;
    }
    
    .section-title {
        font-size: 28px;
    }
    
    .products-grid,
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
    
    .modal-content {
        margin: var(--spacing-md);
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .hero-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .btn-lg {
        padding: var(--spacing-md);
        width: 100%;
        max-width: 200px;
    }
}

/* 信息提示样式 */
.info-note {
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    margin: var(--spacing-md) 0;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 14px;
}

.info-note.success {
    background-color: #155724;
    color: #d4edda;
    border: 1px solid #c3e6cb;
}

.info-note.warning {
    background-color: #856404;
    color: #fff3cd;
    border: 1px solid #ffeaa7;
}

.info-note.error {
    background-color: #721c24;
    color: #f8d7da;
    border: 1px solid #f5c6cb;
}

/* 重启提示样式 */
.restart-prompt {
    padding: var(--spacing-md);
    background-color: var(--bg-tertiary);
    border-radius: var(--radius-md);
    margin: var(--spacing-md) 0;
    border-left: 4px solid #ffc107;
}

.restart-prompt p {
    margin: var(--spacing-xs) 0;
    line-height: 1.5;
}

.restart-prompt strong {
    color: #ffc107;
}