/* 基础布局样式 */
.container {
    display: flex;
    min-height: 100vh;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

.sidebar {
    width: 280px;
    background: #f8f9fa;
    border-right: 1px solid #e9ecef;
    padding: 20px;
    overflow-y: auto;
    height: 100vh;
    position: fixed;
    left: 0;
    top: 0;
}

.sidebar h1 {
    font-size: 1.5rem;
    margin-bottom: 2rem;
    color: #333;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    margin-bottom: 0.5rem;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    font-weight: 500;
}

.nav-item:hover {
    background: #e9ecef;
    transform: translateX(4px);
}

.nav-item.active {
    background: #007bff;
    color: white;
    box-shadow: 0 2px 8px rgba(0,123,255,0.3);
}

.content {
    flex: 1;
    margin-left: 280px;
    padding: 2rem;
    min-height: 100vh;
}

.tool-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
    animation: fadeIn 0.5s ease-out;
}

.tool-card {
    background: white;
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border: 1px solid #e9ecef;
}

.tool-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
    border-color: #007bff;
}

.tool-card .icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    display: block;
}

.tool-card h3 {
    margin-bottom: 0.5rem;
    color: #333;
    font-size: 1.25rem;
}

.tool-card p {
    color: #666;
    line-height: 1.5;
    font-size: 0.9rem;
}

.tool-page {
    animation: slideIn 0.3s ease-out;
}

.back-btn {
    background: #6c757d;
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    cursor: pointer;
    margin-bottom: 2rem;
    font-size: 1rem;
    transition: all 0.2s ease;
}

.back-btn:hover {
    background: #5a6268;
    transform: translateX(-2px);
}

.tool-content {
    background: white;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    min-height: 600px;
}

/* 加载状态样式 */
.loading {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 200px;
    font-size: 1.1rem;
    color: #666;
    background: #f8f9fa;
    border-radius: 8px;
    animation: pulse 1.5s ease-in-out infinite;
}

/* 工具加载状态 */
.loading-tools {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 400px;
    color: #666;
}

.loading-tools .spinner {
    width: 40px;
    height: 40px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #007bff;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 1rem;
}

/* 图片懒加载样式 */
img.loading {
    background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    filter: blur(5px);
    transition: all 0.3s ease;
}

img.loaded {
    animation: fadeIn 0.3s ease-out;
    filter: blur(0);
}

img.error {
    background: #f8f9fa;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #999;
    font-size: 0.9rem;
}

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

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

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.6;
    }
}

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

@keyframes shimmer {
    0% {
        background-position: -200% 0;
    }
    100% {
        background-position: 200% 0;
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .sidebar {
        width: 100%;
        height: auto;
        position: relative;
        border-right: none;
        border-bottom: 1px solid #e9ecef;
    }
    
    .content {
        margin-left: 0;
        padding: 1rem;
    }
    
    .tool-list {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
}