* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
}

:root {
    --primary-color: #4361ee;
    --secondary-color: #3a0ca3;
    --accent-color: #4cc9f0;
    --light-bg: #f8f9fa;
    --card-bg: #ffffff;
    --text-primary: #2b2d42;
    --text-secondary: #6c757d;
    --gradient-primary: linear-gradient(135deg, #4361ee, #3a0ca3);
    --gradient-secondary: linear-gradient(135deg, #4cc9f0, #4361ee);
    --gradient-accent: linear-gradient(135deg, #f72585, #7209b7);
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    --shadow-hover: 0 20px 40px rgba(0, 0, 0, 0.12);
    --border-radius: 16px;
    --transition: all 0.3s ease;
}

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

/* 侧边导航 */
.sidebar {
    width: 280px;
    position: fixed;
    left: 0;
    top: 0;
    height: 100vh;
    background: var(--gradient-primary);
    color: white;
    padding: 2rem 1.5rem;
    z-index: 100;
    overflow-y: auto;
    box-shadow: 5px 0 15px rgba(0, 0, 0, 0.1);
}

.logo-area {
    display: flex;
    align-items: center;
    margin-bottom: 2.5rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
}

.logo-icon {
    font-size: 2.2rem;
    margin-right: 12px;
    color: var(--accent-color);
}

.logo-text {
    font-size: 1.8rem;
    font-weight: 800;
    letter-spacing: 0.5px;
}

.logo-subtext {
    font-size: 0.8rem;
    opacity: 0.9;
    margin-top: 3px;
    letter-spacing: 0.3px;
}

.ai-tag {
    background: var(--gradient-accent);
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: bold;
    margin-top: 8px;
    display: inline-block;
}

.nav-category {
    margin-bottom: 2.5rem;
}

.category-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 1.2rem;
    display: flex;
    align-items: center;
    padding-left: 10px;
    border-left: 4px solid var(--accent-color);
}

.category-title i {
    margin-right: 10px;
    font-size: 1.2rem;
}

.nav-links {
    list-style: none;
}

.nav-links li {
    margin-bottom: 0.8rem;
}

.nav-links a {
    color: rgba(255, 255, 255, 0.85);
    text-decoration: none;
    padding: 0.8rem 1rem;
    border-radius: 12px;
    display: flex;
    align-items: center;
    transition: var(--transition);
}

.nav-links a:hover, .nav-links a.active {
    background: rgba(255, 255, 255, 0.15);
    color: white;
    transform: translateX(5px);
}

.nav-icon {
    width: 36px;
    height: 36px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 12px;
    font-size: 1.1rem;
}

.nav-text h4 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 3px;
}

.nav-text p {
    font-size: 0.8rem;
    opacity: 0.8;
}

.keywords-section {
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
}

.keywords-title {
    font-size: 0.95rem;
    margin-bottom: 1rem;
    opacity: 0.9;
}

.keywords {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.keyword {
    background: rgba(255, 255, 255, 0.15);
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 0.75rem;
    transition: var(--transition);
}

.keyword:hover {
    background: rgba(255, 255, 255, 0.25);
    transform: translateY(-2px);
}

/* 主内容区域 */
.main-content {
    margin-left: 280px;
    padding: 2rem 3rem;
    min-height: 100vh;
}

.page-header {
    margin-bottom: 3rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}

.page-title {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.page-subtitle {
    font-size: 1.1rem;
    color: var(--text-secondary);
   
}

/* 工具卡片区域 */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 2rem;
    margin-bottom: 4rem;
}

.tool-card {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid rgba(0, 0, 0, 0.05);
}

.tool-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-hover);
}

.tool-header {
    padding: 1.8rem;
    background: var(--gradient-secondary);
    color: white;
    position: relative;
}

.tool-header::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 10px;
    background: rgba(255, 255, 255, 0.2);
}

.tool-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.8rem;
    display: flex;
    align-items: center;
}

.tool-icon {
    width: 50px;
    height: 50px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 15px;
    font-size: 1.5rem;
}

.tool-desc {
    font-size: 0.95rem;
    opacity: 0.9;
}

.tool-links {
    padding: 1.8rem;
}

.tool-link {
    display: flex;
    align-items: center;
    padding: 1.2rem;
    border-radius: 12px;
    margin-bottom: 1rem;
    text-decoration: none;
    color: var(--text-primary);
    background: rgba(67, 97, 238, 0.05);
    transition: var(--transition);
    border: 1px solid rgba(67, 97, 238, 0.1);
}

.tool-link:last-child {
    margin-bottom: 0;
}

.tool-link:hover {
    background: rgba(67, 97, 238, 0.1);
    transform: translateX(5px);
    border-color: rgba(67, 97, 238, 0.2);
}

.link-icon {
    width: 40px;
    height: 40px;
    background: var(--gradient-primary);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    margin-right: 15px;
    font-size: 1.1rem;
}

.link-text h4 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 5px;
}

.link-text p {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* AI特色区域 */
.ai-showcase {
    background: var(--gradient-primary);
    border-radius: var(--border-radius);
    padding: 3rem;
    color: white;
    margin-bottom: 3rem;
    position: relative;
    overflow: hidden;
}

.ai-showcase::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 300px;
    height: 300px;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><path fill="rgba(255,255,255,0.05)" d="M30,30 Q50,10 70,30 T90,50 Q70,70 50,90 T30,70 Q10,50 30,30Z"/></svg>');
    background-size: contain;
    opacity: 0.5;
}

.ai-title {
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    position: relative;
    z-index: 1;
}

.ai-desc {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    opacity: 0.9;
    max-width: 800px;
    position: relative;
    z-index: 1;
}

.ai-features {
    display: flex;
    gap: 1.5rem;
    position: relative;
    z-index: 1;
}

.ai-feature {
    background: rgba(255, 255, 255, 0.15);
    padding: 1.5rem;
    border-radius: 12px;
    flex: 1;
    backdrop-filter: blur(10px);
    transition: var(--transition);
}

.ai-feature:hover {
    background: rgba(255, 255, 255, 0.25);
    transform: translateY(-5px);
}

.ai-feature i {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--accent-color);
}

.ai-feature h4 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

.ai-feature p {
    font-size: 0.9rem;
    opacity: 0.9;
}

/* 页脚 */
footer {
    background: var(--text-primary);
    color: rgba(255, 255, 255, 0.8);
    padding: 2.5rem 0;
    text-align: center;
    margin-left: 280px;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.footer-logo {
    font-size: 1.8rem;
    font-weight: 800;
    color: white;
    margin-bottom: 1rem;
}

.footer-tagline {
    font-size: 1rem;
    margin-bottom: 1.5rem;
    opacity: 0.9;
}

.copyright {
    margin-top: 2rem;
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.6);
}

/* 响应式设计 */
@media (max-width: 1200px) {
    .sidebar {
        width: 250px;
    }
    
    .main-content {
        margin-left: 250px;
        padding: 2rem;
    }
    
    footer {
        margin-left: 250px;
    }
}

@media (max-width: 992px) {
    .sidebar {
        transform: translateX(-100%);
        transition: transform 0.3s ease;
        width: 280px;
    }
    
    .sidebar.active {
        transform: translateX(0);
    }
    
    .main-content {
        margin-left: 0;
        padding: 1.5rem;
    }
    
    footer {
        margin-left: 0;
    }
    
    .menu-toggle {
        display: block;
        position: fixed;
        top: 1.5rem;
        right: 1.5rem;
        z-index: 101;
        background: var(--gradient-primary);
        color: white;
        border: none;
        width: 50px;
        height: 50px;
        border-radius: 10px;
        font-size: 1.5rem;
        cursor: pointer;
        box-shadow: var(--shadow);
    }
    
    .overlay {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(0, 0, 0, 0.5);
        z-index: 99;
        display: none;
    }
    
    .overlay.active {
        display: block;
    }
    
    .tools-grid {
        grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    }
    
    .ai-features {
        flex-direction: column;
    }
}

@media (max-width: 768px) {
    .page-title {
        font-size: 2rem;
    }
    
    .tools-grid {
        grid-template-columns: 1fr;
    }
    
    .ai-showcase {
        padding: 2rem;
    }
    
    .ai-title {
        font-size: 1.8rem;
    }
}

@media (max-width: 480px) {
    .main-content {
        padding: 1rem;
    }
    
    .page-title {
        font-size: 1.8rem;
    }
    
    .tool-card {
        margin-bottom: 1.5rem;
    }
    
    .ai-showcase {
        padding: 1.5rem;
    }
}

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

.fade-in {
    animation: fadeInUp 0.6s ease forwards;
}

.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }
.delay-4 { animation-delay: 0.4s; }

/* 滚动条美化 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: rgba(0, 0, 0, 0.05);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--secondary-color);
}