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

:root {
    --primary-color: #4F46E5;
    --primary-dark: #4338CA;
    --secondary-color: #06B6D4;
    --success-color: #10B981;
    --warning-color: #F59E0B;
    --danger-color: #EF4444;
    --bg-color: #F9FAFB;
    --card-bg: #FFFFFF;
    --text-primary: #111827;
    --text-secondary: #6B7280;
    --border-color: #E5E7EB;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 2rem 1rem;
    color: var(--text-primary);
}

.container {
    max-width: 1400px;
    margin: 0 auto;
}

/* 头部样式 */
.main-header {
    text-align: center;
    margin-bottom: 3rem;
    animation: fadeInDown 0.6s ease-out;
}

.header-content h1 {
    font-size: 3.5rem;
    font-weight: 800;
    color: white;
    margin-bottom: 0.5rem;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.header-subtitle {
    font-size: 1.25rem;
    color: rgba(255, 255, 255, 0.95);
    font-weight: 400;
}

/* 工具网格 */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

/* 工具卡片 */
.tool-card {
    background: var(--card-bg);
    border-radius: 16px;
    padding: 2rem;
    box-shadow: var(--shadow-lg);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
    animation: fadeInUp 0.6s ease-out backwards;
}

.tool-card:nth-child(1) { animation-delay: 0.1s; }
.tool-card:nth-child(2) { animation-delay: 0.2s; }
.tool-card:nth-child(3) { animation-delay: 0.3s; }
.tool-card:nth-child(4) { animation-delay: 0.4s; }

.tool-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.3s ease;
}

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

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

/* 工具图标 */
.tool-icon {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    transition: transform 0.3s ease;
}

.tool-card:hover .tool-icon {
    transform: scale(1.1) rotate(5deg);
}

.tool-icon svg {
    width: 32px;
    height: 32px;
    color: white;
}

/* 不同类别的图标颜色 */
.tool-card[data-category="data"] .tool-icon {
    background: linear-gradient(135deg, #667eea, #764ba2);
}

.tool-card[data-category="security"] .tool-icon {
    background: linear-gradient(135deg, #f093fb, #f5576c);
}

.tool-card[data-category="media"] .tool-icon {
    background: linear-gradient(135deg, #4facfe, #00f2fe);
}

.tool-card[data-category="network"] .tool-icon {
    background: linear-gradient(135deg, #43e97b, #38f9d7);
}

/* 工具内容 */
.tool-content {
    margin-bottom: 1.5rem;
}

.tool-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
}

.tool-description {
    font-size: 1rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1rem;
}

/* 特性标签 */
.tool-features {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.feature-tag {
    display: inline-block;
    padding: 0.375rem 0.75rem;
    background: var(--bg-color);
    color: var(--text-secondary);
    border-radius: 6px;
    font-size: 0.875rem;
    font-weight: 500;
    border: 1px solid var(--border-color);
    transition: all 0.2s ease;
}

.tool-card:hover .feature-tag {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* 工具链接 */
.tool-link {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 1.5rem;
    background: var(--primary-color);
    color: white;
    text-decoration: none;
    border-radius: 12px;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
    margin-top: auto;
}

.tool-link:hover {
    background: var(--primary-dark);
    transform: translateX(4px);
}

.arrow-icon {
    width: 20px;
    height: 20px;
    transition: transform 0.3s ease;
}

.tool-link:hover .arrow-icon {
    transform: translateX(4px);
}

/* 页脚 */
.main-footer {
    text-align: center;
    padding: 2rem 0;
    animation: fadeIn 0.8s ease-out 0.5s backwards;
}

.footer-content {
    color: white;
}

.footer-content p {
    margin-bottom: 0.5rem;
    font-size: 0.95rem;
}

.footer-info {
    font-weight: 600;
    opacity: 0.9;
}

/* 动画 */
@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    body {
        padding: 1rem 0.5rem;
    }

    .header-content h1 {
        font-size: 2.5rem;
    }

    .header-subtitle {
        font-size: 1rem;
    }

    .tools-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .tool-card {
        padding: 1.5rem;
    }

    .tool-title {
        font-size: 1.5rem;
    }

    .tool-description {
        font-size: 0.9rem;
    }
}

@media (max-width: 480px) {
    .header-content h1 {
        font-size: 2rem;
    }

    .tool-icon {
        width: 56px;
        height: 56px;
    }

    .tool-icon svg {
        width: 28px;
        height: 28px;
    }
}

/* 打印样式 */
@media print {
    body {
        background: white;
        padding: 0;
    }

    .tool-card {
        break-inside: avoid;
        box-shadow: none;
        border: 1px solid var(--border-color);
    }

    .tool-link {
        display: none;
    }
}