/* Number Systems Hub Styles */
.number-systems-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* Hero Section */
.hero-section {
    text-align: center;
    padding: 60px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 12px;
    margin-bottom: 40px;
}

.hero-content h1 {
    font-size: 2.5rem;
    margin-bottom: 16px;
    font-weight: 700;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 30px;
    opacity: 0.9;
}

/* Quick Calculator */
.quick-calculator {
    background: #f8f9fa;
    padding: 30px;
    border-radius: 12px;
    margin-bottom: 40px;
    border: 1px solid #e9ecef;
}

.quick-calculator h2 {
    margin-bottom: 20px;
    color: #2c3e50;
}

.calculator-widget {
    max-width: 600px;
    margin: 0 auto;
}

.input-group {
    display: flex;
    gap: 10px;
    align-items: center;
    flex-wrap: wrap;
}

.input-group input,
.input-group select,
.input-group button {
    padding: 12px 16px;
    border: 2px solid #e9ecef;
    border-radius: 8px;
    font-size: 16px;
}

.input-group input {
    flex: 1;
    min-width: 150px;
}

.input-group select {
    min-width: 120px;
}

.input-group button {
    background: #667eea;
    color: white;
    border: none;
    cursor: pointer;
    transition: background 0.3s;
}

.input-group button:hover {
    background: #5a6fd8;
}

.convert-arrow {
    font-size: 20px;
    font-weight: bold;
    color: #667eea;
}

.result-area {
    margin-top: 20px;
    padding: 20px;
    background: white;
    border-radius: 8px;
    border-left: 4px solid #667eea;
}

.result-value {
    font-size: 1.3rem;
    font-weight: bold;
    color: #2c3e50;
    margin-bottom: 10px;
}

.step-by-step {
    color: #6c757d;
    font-size: 0.9rem;
}

/* Quick Access */
.quick-access {
    margin-bottom: 40px;
}

.quick-access h2 {
    margin-bottom: 20px;
    color: #2c3e50;
}

.quick-tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.quick-tool {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 30px 20px;
    background: white;
    border: 2px solid #e9ecef;
    border-radius: 12px;
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

.quick-tool:hover {
    transform: translateY(-5px);
    border-color: #667eea;
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.15);
}

.tool-icon {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.tool-name {
    font-weight: 600;
    color: #2c3e50;
    text-align: center;
}

/* Categories Grid */
.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.category-card {
    background: white;
    border: 1px solid #e9ecef;
    border-radius: 12px;
    padding: 25px;
    transition: transform 0.3s ease;
}

.category-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 5px 20px rgba(0,0,0,0.1);
}

.category-header {
    display: flex;
    align-items: center;
    margin-bottom: 15px;
}

.category-icon {
    font-size: 2rem;
    margin-right: 15px;
}

.category-header h3 {
    margin: 0;
    color: #2c3e50;
}

.category-card p {
    color: #6c757d;
    margin-bottom: 20px;
}

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

.category-links li {
    margin-bottom: 8px;
}

.category-links a {
    color: #667eea;
    text-decoration: none;
    transition: color 0.3s;
}

.category-links a:hover {
    color: #5a6fd8;
    text-decoration: underline;
}

/* Reference Section */
.reference-section {
    margin-bottom: 40px;
}

.reference-section h2 {
    margin-bottom: 30px;
    color: #2c3e50;
}

.reference-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
}

.system-card {
    background: white;
    border: 1px solid #e9ecef;
    border-radius: 12px;
    padding: 25px;
    transition: transform 0.3s ease;
}

.system-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 5px 20px rgba(0,0,0,0.1);
}

.system-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
    padding-bottom: 15px;
    border-bottom: 2px solid;
}

.system-header.binary { border-color: #e74c3c; }
.system-header.decimal { border-color: #3498db; }
.system-header.hexadecimal { border-color: #9b59b6; }
.system-header.octal { border-color: #f39c12; }

.system-header h3 {
    margin: 0;
    font-size: 1.2rem;
}

.system-digits {
    background: #f8f9fa;
    padding: 4px 8px;
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: 600;
}

.system-card p {
    color: #6c757d;
    margin-bottom: 15px;
}

.system-card ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.system-card li {
    margin-bottom: 8px;
    color: #495057;
}

/* Articles Grid */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 30px;
}

.article-card {
    background: white;
    border: 1px solid #e9ecef;
    border-radius: 12px;
    overflow: hidden;
    transition: transform 0.3s ease;
}

.article-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
}

.article-image {
    height: 200px;
    overflow: hidden;
}

.article-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.article-placeholder {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #f8f9fa;
    font-size: 3rem;
}

.article-content {
    padding: 20px;
}

.article-content h3 {
    margin: 0 0 10px 0;
}

.article-content h3 a {
    color: #2c3e50;
    text-decoration: none;
}

.article-content h3 a:hover {
    color: #667eea;
}

.article-content p {
    color: #6c757d;
    margin-bottom: 15px;
}

.article-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.9rem;
}

.date {
    color: #6c757d;
}

.read-more {
    color: #667eea;
    text-decoration: none;
    font-weight: 600;
}

.read-more:hover {
    text-decoration: underline;
}

/* FAQ Section */
.faq-section {
    margin-bottom: 40px;
}

.faq-section h2 {
    margin-bottom: 30px;
    color: #2c3e50;
}

.faq-item {
    border: 1px solid #e9ecef;
    border-radius: 8px;
    margin-bottom: 15px;
    overflow: hidden;
}

.faq-question {
    padding: 20px;
    background: #f8f9fa;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: background 0.3s;
}

.faq-question:hover {
    background: #e9ecef;
}

.faq-question h3 {
    margin: 0;
    font-size: 1.1rem;
    color: #2c3e50;
}

.faq-toggle {
    font-size: 1.5rem;
    font-weight: bold;
    color: #667eea;
}

.faq-answer {
    padding: 0 20px;
    display: none;
}

.faq-answer p {
    padding: 20px 0;
    margin: 0;
    color: #495057;
    border-top: 1px solid #e9ecef;
}

/* CTA Section */
.cta-section {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 60px 40px;
    border-radius: 12px;
    text-align: center;
}

.cta-content h2 {
    margin-bottom: 16px;
    font-size: 2rem;
}

.cta-content p {
    margin-bottom: 30px;
    font-size: 1.1rem;
    opacity: 0.9;
}

.cta-button {
    display: inline-block;
    padding: 15px 30px;
    background: white;
    color: #667eea;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    transition: transform 0.3s;
}

.cta-button:hover {
    transform: translateY(-2px);
    color: #5a6fd8;
}

/* Search Box */
.search-box {
    max-width: 400px;
    margin: 0 auto;
    position: relative;
}

.search-box input {
    width: 100%;
    padding: 12px 50px 12px 20px;
    border: 2px solid rgba(255,255,255,0.3);
    border-radius: 25px;
    background: rgba(255,255,255,0.2);
    color: white;
    font-size: 16px;
}

.search-box input::placeholder {
    color: rgba(255,255,255,0.7);
}

.search-box button {
    position: absolute;
    right: 10px;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: white;
    cursor: pointer;
}

.view-all-container {
    text-align: center;
}

.view-all-btn {
    display: inline-block;
    padding: 12px 30px;
    background: #667eea;
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    transition: background 0.3s;
}

.view-all-btn:hover {
    background: #5a6fd8;
}

/* Responsive Design */
@media (max-width: 768px) {
    .number-systems-container {
        padding: 10px;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .input-group {
        flex-direction: column;
    }
    
    .input-group input,
    .input-group select {
        width: 100%;
    }
    
    .quick-tools-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    }
    
    .categories-grid {
        grid-template-columns: 1fr;
    }
    
    .reference-grid {
        grid-template-columns: 1fr;
    }
    
    .articles-grid {
        grid-template-columns: 1fr;
    }
    
    .cta-section {
        padding: 40px 20px;
    }
}