* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: 700;
    color: #667eea;
}

.logo i {
    margin-right: 0.5rem;
    font-size: 1.8rem;
}

.search-container {
    position: relative;
    max-width: 400px;
    width: 100%;
}

.search-input {
    width: 100%;
    padding: 12px 20px 12px 45px;
    border: 2px solid #e1e5e9;
    border-radius: 25px;
    font-size: 1rem;
    outline: none;
    transition: all 0.3s ease;
    background: white;
}

.search-input:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.search-icon {
    position: absolute;
    left: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: #999;
}

/* Main Content */
.main {
    padding: 2rem 0;
}

.hero {
    text-align: center;
    margin-bottom: 3rem;
    color: white;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

.hero p {
    font-size: 1.2rem;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto;
}

/* Content Layout */
.content-wrapper {
    display: flex;
    gap: 2rem;
    align-items: flex-start;
}

/* Left Navigation */
.category-nav {
    position: sticky;
    top: 100px;
    width: 280px;
    flex-shrink: 0;
    background: white;
    border-radius: 20px;
    padding: 1.5rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    max-height: calc(100vh - 120px);
    overflow-y: auto;
}

.nav-header {
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid #f0f0f0;
}

.nav-header h3 {
    margin: 0;
    color: #333;
    font-size: 1.2rem;
    font-weight: 600;
    display: flex;
    align-items: center;
}

.nav-header h3 i {
    margin-right: 0.5rem;
    color: #667eea;
}

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

.nav-list li {
    margin-bottom: 0.5rem;
}

.nav-list li.hidden {
    display: none;
}

.nav-link {
    display: flex;
    align-items: center;
    padding: 0.75rem 1rem;
    color: #666;
    text-decoration: none;
    border-radius: 10px;
    transition: all 0.3s ease;
    font-size: 0.9rem;
    font-weight: 500;
}

.nav-link:hover {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    transform: translateX(5px);
}

.nav-link.active {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
}

.nav-link i {
    margin-right: 0.75rem;
    width: 16px;
    text-align: center;
}

/* Categories */
.categories {
    flex: 1;
    min-width: 0;
}

.category {
    background: white;
    border-radius: 20px;
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    scroll-margin-top: 100px;
}

.category:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

.category-header {
    margin-bottom: 2rem;
}

.category-header h2 {
    font-size: 1.8rem;
    font-weight: 600;
    color: #333;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
}

.category-header h2 i {
    margin-right: 0.75rem;
    color: #667eea;
    font-size: 1.5rem;
}

.category-header p {
    color: #666;
    font-size: 1rem;
}

/* Tools Grid */
.tools-grid {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.tool-card {
    background: #f8f9fa;
    border-radius: 12px;
    padding: 1.5rem;
    border: 1px solid #e9ecef;
    transition: all 0.3s ease;
}

.tool-card:hover {
    background: #fff;
    border-color: #667eea;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.1);
}

.tool-card h3 {
    font-size: 1.1rem;
    font-weight: 600;
    color: #333;
    margin: 0 0 1rem 0;
}

.tool-links {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tool-link {
    display: inline-block;
    padding: 0.5rem 1rem;
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    text-decoration: none;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
}

.tool-link:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.3);
    background: linear-gradient(135deg, #5a67d8, #6b46c1);
}

.tool-link.hidden {
    display: none;
}

/* Footer */
.footer {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    color: white;
    text-align: center;
    padding: 2rem 0;
    margin-top: 3rem;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .content-wrapper {
        flex-direction: column;
    }
    
    .category-nav {
        position: static;
        width: 100%;
        max-height: none;
        margin-bottom: 2rem;
    }
    
    .nav-list {
        display: flex;
        flex-wrap: wrap;
        gap: 0.5rem;
    }
    
    .nav-list li {
        margin-bottom: 0;
    }
    
    .nav-link {
        padding: 0.5rem 1rem;
        font-size: 0.8rem;
    }
}

@media (max-width: 768px) {
    .nav {
        flex-direction: column;
        gap: 1rem;
    }
    
    .search-container {
        max-width: 100%;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero p {
        font-size: 1rem;
    }
    
    .category {
        padding: 1.5rem;
    }
    
    .category-header h2 {
        font-size: 1.5rem;
    }
    
    .tool-links {
        justify-content: flex-start;
    }
    
    .nav-header {
        display: none;
    }
    
    .nav-list {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .category {
        padding: 1rem;
    }
    
    .tool-card {
        padding: 1rem;
    }
    
    .tool-link {
        font-size: 0.8rem;
        padding: 0.4rem 0.8rem;
    }
}

/* Search functionality styles */
.category.hidden {
    display: none;
}

.tool-card.hidden {
    display: none;
}

.no-results {
    text-align: center;
    padding: 3rem;
    color: white;
    font-size: 1.2rem;
}

/* Animation for smooth transitions */
.category {
    animation: fadeInUp 0.6s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Scrollbar styling */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f1f1;
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(135deg, #667eea, #764ba2);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(135deg, #5a67d8, #6b46c1);
}