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

:root {
    /* 主色调 */
    --primary-color: #4285f4;
    --primary-dark: #3367d6;
    --primary-light: #5a9cff;
    
    /* 辅助色 */
    --secondary-color: #34a853;
    --accent-color: #fbbc04;
    --warning-color: #ea4335;
    
    /* 中性色 */
    --text-primary: #202124;
    --text-secondary: #5f6368;
    --text-tertiary: #9aa0a6;
    --background-primary: #ffffff;
    --background-secondary: #f8f9fa;
    --background-tertiary: #e8f0fe;
    --border-color: #dadce0;
    
    /* 字体 */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    
    /* 阴影 */
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
    --shadow-xl: 0 20px 25px rgba(0,0,0,0.1);
    
    /* 边界半径 */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    
    /* 间距 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: all 0.3s ease;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo {
    display: flex;
    align-items: center;
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--primary-color);
    text-decoration: none;
}

.nav-logo i {
    margin-right: var(--spacing-sm);
    font-size: 1.5rem;
}

.nav-menu {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
}

.nav-menu li {
    margin-left: var(--spacing-xl);
}

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

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

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: width 0.3s ease;
}

.nav-menu a:hover::after {
    width: 100%;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.nav-toggle .bar {
    width: 25px;
    height: 3px;
    background-color: var(--text-primary);
    margin: 3px 0;
    transition: 0.3s;
}

/* 英雄区 */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, var(--background-tertiary) 0%, var(--background-secondary) 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: radial-gradient(circle at 20% 50%, rgba(66, 133, 244, 0.1) 0%, transparent 50%),
                      radial-gradient(circle at 80% 20%, rgba(52, 168, 83, 0.1) 0%, transparent 50%);
    pointer-events: none;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
    align-items: center;
}

.hero-content {
    position: relative;
    z-index: 2;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    background: var(--background-primary);
    color: var(--text-secondary);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-xl);
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
}

.hero-badge span:first-child {
    margin-right: var(--spacing-sm);
}

.update-time {
    background: var(--primary-color);
    color: white;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-md);
    font-size: 0.75rem;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--spacing-lg);
    color: var(--text-primary);
}

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

.hero-description {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-2xl);
    line-height: 1.6;
}

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

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
}

.floating-card {
    background: var(--background-primary);
    padding: var(--spacing-2xl);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    text-align: center;
    animation: float 6s ease-in-out infinite;
    position: relative;
}

.floating-card i {
    font-size: 4rem;
    color: var(--primary-color);
    margin-bottom: var(--spacing-md);
}

.floating-card h3 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.floating-card p {
    color: var(--text-secondary);
}

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

/* 按钮样式 */
.btn {
    display: inline-flex;
    align-items: center;
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--radius-lg);
    text-decoration: none;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.btn i {
    margin-right: var(--spacing-sm);
}

.btn-primary {
    background: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: var(--background-primary);
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-2px);
}

/* 区块标题 */
.section-header {
    text-align: center;
    margin-bottom: var(--spacing-3xl);
}

.section-header h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.section-header p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* 方案对比表 */
.comparison {
    padding: var(--spacing-3xl) 0;
    background: var(--background-secondary);
}

.comparison-table-wrapper {
    overflow-x: auto;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
}

.comparison-table {
    width: 100%;
    background: var(--background-primary);
    border-collapse: collapse;
    min-width: 800px;
}

.comparison-table th,
.comparison-table td {
    padding: var(--spacing-lg);
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.comparison-table th {
    background: var(--background-tertiary);
    font-weight: 600;
    color: var(--text-primary);
    position: sticky;
    top: 0;
}

.comparison-table tr.highlight {
    background: rgba(66, 133, 244, 0.05);
}

.comparison-table tr.disabled {
    opacity: 0.6;
}

.method-name {
    display: flex;
    align-items: center;
    font-weight: 600;
}

.method-name i {
    margin-right: var(--spacing-sm);
    color: var(--primary-color);
}

.cost {
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 600;
}

.cost.free {
    background: rgba(52, 168, 83, 0.1);
    color: var(--secondary-color);
}

.cost.affordable {
    background: rgba(251, 188, 4, 0.1);
    color: #e8710a;
}

.cost.expensive {
    background: rgba(234, 67, 53, 0.1);
    color: var(--warning-color);
}

.cost.disabled {
    background: rgba(0, 0, 0, 0.1);
    color: var(--text-tertiary);
}

.rating.recommended {
    color: var(--secondary-color);
}

/* 详细方案 */
.methods {
    padding: var(--spacing-3xl) 0;
}

.methods-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: var(--spacing-xl);
}

.method-card {
    background: var(--background-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
    position: relative;
}

.method-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

.method-card.featured {
    border-color: var(--primary-color);
    background: linear-gradient(135deg, rgba(66, 133, 244, 0.02) 0%, rgba(52, 168, 83, 0.02) 100%);
}

.method-card.disabled {
    opacity: 0.6;
    background: var(--background-secondary);
}

.method-header {
    display: flex;
    align-items: flex-start;
    margin-bottom: var(--spacing-lg);
    position: relative;
}

.method-icon {
    width: 60px;
    height: 60px;
    background: var(--background-tertiary);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: var(--spacing-md);
    flex-shrink: 0;
}

.method-icon i {
    font-size: 1.5rem;
    color: var(--primary-color);
}

.method-title h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
    color: var(--text-primary);
}

.method-subtitle {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.method-badge {
    position: absolute;
    top: 0;
    right: 0;
    background: var(--primary-color);
    color: white;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-md);
    font-size: 0.75rem;
    font-weight: 600;
}

.method-badge.disabled {
    background: var(--text-tertiary);
}

.method-content h4 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.method-content ul {
    list-style: none;
    margin-bottom: var(--spacing-lg);
}

.method-content li {
    padding: var(--spacing-xs) 0;
    position: relative;
    padding-left: var(--spacing-lg);
}

.method-content li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--secondary-color);
    font-weight: bold;
}

.method-action {
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
}

.contact-info {
    margin-top: var(--spacing-md);
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

.note {
    margin-top: var(--spacing-sm);
    font-size: 0.875rem;
    color: var(--text-tertiary);
    font-style: italic;
}

/* 选择建议 */
.recommendation {
    padding: var(--spacing-3xl) 0;
    background: var(--background-secondary);
}

.recommendation-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-xl);
}

.recommendation-card {
    background: var(--background-primary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-xl);
    text-align: center;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
}

.recommendation-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.recommendation-icon {
    width: 80px;
    height: 80px;
    background: var(--background-tertiary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--spacing-lg);
}

.recommendation-icon i {
    font-size: 2rem;
    color: var(--primary-color);
}

.recommendation-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.recommendation-card p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* 页脚 */
.footer {
    background: var(--text-primary);
    color: white;
    padding: var(--spacing-3xl) 0 var(--spacing-xl);
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: var(--spacing-2xl);
    align-items: center;
    margin-bottom: var(--spacing-xl);
}

.footer-logo {
    display: flex;
    align-items: center;
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

.footer-logo i {
    margin-right: var(--spacing-sm);
    font-size: 1.5rem;
    color: var(--primary-light);
}

.footer-info p {
    color: rgba(255, 255, 255, 0.8);
}

.footer-stats {
    display: flex;
    gap: var(--spacing-xl);
}

.stat {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-light);
}

.stat-label {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.8);
}

.footer-bottom {
    padding-top: var(--spacing-xl);
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    text-align: center;
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.875rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: var(--background-primary);
        width: 100%;
        text-align: center;
        transition: left 0.3s ease, opacity 0.3s ease;
        box-shadow: var(--shadow-md);
        border-top: 1px solid var(--border-color);
        opacity: 0;
        z-index: 999;
        backdrop-filter: blur(10px);
        padding: var(--spacing-lg) 0;
    }

    .nav-menu.active {
        left: 0;
        opacity: 1;
    }

    .nav-menu li {
        margin: var(--spacing-md) 0;
        transform: translateY(20px);
        opacity: 0;
        transition: all 0.3s ease;
    }
    
    .nav-menu.active li {
        transform: translateY(0);
        opacity: 1;
    }
    
    .nav-menu.active li:nth-child(1) { transition-delay: 0.1s; }
    .nav-menu.active li:nth-child(2) { transition-delay: 0.2s; }
    .nav-menu.active li:nth-child(3) { transition-delay: 0.3s; }
    .nav-menu.active li:nth-child(4) { transition-delay: 0.4s; }

    .nav-toggle {
        display: flex;
    }
    
    /* Enhanced hamburger animation */
    .nav-toggle.active .bar:nth-child(1) {
        transform: rotate(-45deg) translate(-5px, 6px);
    }
    
    .nav-toggle.active .bar:nth-child(2) {
        opacity: 0;
    }
    
    .nav-toggle.active .bar:nth-child(3) {
        transform: rotate(45deg) translate(-5px, -6px);
    }

    .hero-container {
        grid-template-columns: 1fr;
        gap: var(--spacing-2xl);
        text-align: center;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-buttons {
        justify-content: center;
        flex-wrap: wrap;
    }

    .methods-grid {
        grid-template-columns: 1fr;
    }

    .recommendation-grid {
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    }

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .footer-stats {
        justify-content: center;
    }

    .comparison-table th,
    .comparison-table td {
        padding: var(--spacing-sm);
        font-size: 0.875rem;
    }
    
    /* Improved mobile table scroll indicator */
    .comparison-table-wrapper::after {
        content: "👈 滑动查看更多";
        position: absolute;
        right: 10px;
        top: 50%;
        transform: translateY(-50%);
        background: rgba(66, 133, 244, 0.9);
        color: white;
        padding: 4px 8px;
        border-radius: 4px;
        font-size: 0.75rem;
        pointer-events: none;
        opacity: 0.8;
        animation: pulse 2s infinite;
    }
    
    .comparison-table-wrapper:hover::after {
        opacity: 0;
    }
}

/* Ultra-small screen improvements */
@media (max-width: 480px) {
    /* Prevent horizontal overflow */
    html, body {
        overflow-x: hidden;
    }
    .container,
    .nav-container,
    .hero-container {
        padding-left: var(--spacing-md);
        padding-right: var(--spacing-md);
    }

    .hero-title {
        font-size: 2rem;
    }

    .section-header h2 {
        font-size: 2rem;
    }

    .btn {
        padding: var(--spacing-sm) var(--spacing-lg);
        font-size: 0.875rem;
    }

    .method-card {
        padding: var(--spacing-lg);
    }

    .recommendation-card {
        padding: var(--spacing-lg);
    }
    
    /* Mobile-specific improvements */
    .hero-badge {
        font-size: 0.75rem;
        padding: var(--spacing-xs) var(--spacing-sm);
    }
    
    .nav-container {
        height: 60px;
    }
    
    .navbar {
        padding: 0;
    }
    
    .hero {
        padding: 100px 0 60px;
    }
    
    .floating-card {
        padding: var(--spacing-lg);
        transform: scale(0.9);
    }
    
    .method-badge {
        position: static;
        display: inline-block;
        margin-top: var(--spacing-xs);
        margin-left: var(--spacing-sm);
    }
}

/* 滚动条样式 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--background-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-tertiary);
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}

/* 选择文本样式 */
::selection {
    background: var(--primary-light);
    color: white;
}

/* 焦点样式 */
.btn:focus,
.nav-menu a:focus {
    outline: 2px solid var(--primary-light);
    outline-offset: 2px;
}

/* 加载动画 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.method-card,
.recommendation-card {
    animation: fadeInUp 0.6s ease-out;
}

/* 表格响应式增强 */
@media (max-width: 768px) {
    .comparison-table-wrapper {
        border-radius: 0;
        margin: 0 -var(--spacing-lg);
        position: relative;
    }
    
    .comparison-table {
        min-width: 600px;
    }
    
    .method-name {
        min-width: 120px;
    }
}

/* 高对比度模式支持 */
@media (prefers-contrast: high) {
    :root {
        --border-color: #000000;
        --text-secondary: #000000;
    }
}

/* 减少动画模式支持 */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Language Selector */
.language-selector {
    margin-right: var(--spacing-md);
}

.language-selector select {
    background: var(--background-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.875rem;
    color: var(--text-primary);
    cursor: pointer;
    outline: none;
    transition: all 0.3s ease;
    min-width: 80px;
}

.language-selector select:hover {
    border-color: var(--primary-color);
    transform: translateY(-1px);
}

.language-selector select:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(66, 133, 244, 0.2);
}

/* Mobile language selector improvements */
@media (max-width: 768px) {
    .language-selector {
        margin-right: 0;
        margin-left: var(--spacing-md);
    }
    
    .language-selector select {
        font-size: 0.8rem;
        padding: var(--spacing-xs);
        min-width: 70px;
    }
}