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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background: #ffffff;
}

/* Containers */
.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 20px;
}

.wide-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    background: #ffffff;
    border-bottom: 1px solid #e5e5e5;
    padding: 20px 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: #1a1a1a;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: #2563eb;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 700;
    font-size: 20px;
}

.logo-text {
    font-size: 20px;
    font-weight: 600;
}

/* Navigation */
nav ul {
    list-style: none;
    display: flex;
    gap: 30px;
}

nav a {
    text-decoration: none;
    color: #555;
    font-weight: 500;
    transition: color 0.2s;
}

nav a:hover {
    color: #2563eb;
}

/* Breadcrumb */
.breadcrumb {
    padding: 20px 0;
    font-size: 0.9em;
    color: #666;
}

.breadcrumb a {
    color: #2563eb;
    text-decoration: none;
}

/* Typography */
h1 {
    font-size: 2.5em;
    margin: 20px 0;
    color: #1a1a1a;
    font-weight: 700;
}

h2 {
    font-size: 1.75em;
    margin: 40px 0 20px 0;
    color: #1a1a1a;
    font-weight: 600;
}

h3 {
    font-size: 1.25em;
    margin: 30px 0 15px 0;
    color: #2a2a2a;
    font-weight: 600;
}

p {
    margin: 18px 0;
    line-height: 1.7;
}

ul, ol {
    margin: 18px 0 18px 30px;
}

li {
    margin: 10px 0;
}

a {
    color: #2563eb;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* Content Blocks */
.definition {
    background: #f0f4ff;
    border-left: 4px solid #2563eb;
    padding: 24px;
    margin: 30px 0;
    font-size: 1.05em;
}

.definition strong {
    color: #1a1a1a;
}

.answer-block {
    background: #f8f9fa;
    padding: 24px;
    margin: 30px 0;
    border-radius: 6px;
    border: 1px solid #e5e5e5;
}

.diagram {
    background: #f8f9fa;
    border: 1px solid #e5e5e5;
    border-radius: 6px;
    padding: 30px;
    margin: 30px 0;
    text-align: center;
}

.diagram-title {
    font-weight: 600;
    margin-bottom: 20px;
    color: #1a1a1a;
}

.diagram-content {
    font-family: 'Courier New', monospace;
    font-size: 0.9em;
    color: #555;
    line-height: 2;
}

/* Cards */
.related-box {
    background: #ffffff;
    border: 1px solid #e5e5e5;
    border-radius: 6px;
    padding: 30px;
    margin: 40px 0;
}

.related-box h3 {
    margin-top: 0;
}

.related-links {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
    margin-top: 20px;
}

.related-link {
    padding: 15px;
    border: 1px solid #e5e5e5;
    border-radius: 4px;
    text-decoration: none;
    color: #333;
    transition: all 0.2s;
}

.related-link:hover {
    border-color: #2563eb;
    background: #f0f4ff;
}

.related-link-title {
    font-weight: 600;
    color: #2563eb;
    margin-bottom: 5px;
}

.related-link-desc {
    font-size: 0.9em;
    color: #666;
}

/* FAQ */
.faq {
    margin: 50px 0;
}

.faq-item {
    margin: 25px 0;
    padding: 25px;
    background: #ffffff;
    border: 1px solid #e5e5e5;
    border-radius: 6px;
}

.faq-question {
    font-weight: 600;
    color: #1a1a1a;
    font-size: 1.1em;
    margin-bottom: 12px;
}

.faq-answer {
    color: #555;
    line-height: 1.7;
}

/* Homepage Specific */
.hero {
    padding: 80px 0 60px 0;
    text-align: center;
}

.hero h1 {
    font-size: 3em;
    margin-bottom: 20px;
    color: #1a1a1a;
    font-weight: 700;
}

.hero p {
    font-size: 1.25em;
    color: #666;
    max-width: 700px;
    margin: 0 auto 40px auto;
}

.concepts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    padding: 40px 0 80px 0;
}

.concept-card {
    background: #ffffff;
    border: 1px solid #e5e5e5;
    border-radius: 8px;
    padding: 30px;
    text-decoration: none;
    color: inherit;
    transition: all 0.2s;
}

.concept-card:hover {
    border-color: #2563eb;
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.1);
    transform: translateY(-2px);
}

.concept-card h2 {
    font-size: 1.5em;
    margin-bottom: 12px;
    color: #1a1a1a;
}

.concept-card p {
    color: #666;
    line-height: 1.6;
}

.concept-icon {
    width: 50px;
    height: 50px;
    background: #f0f4ff;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    font-size: 24px;
}

/* Footer */
footer {
    background: #f8f9fa;
    border-top: 1px solid #e5e5e5;
    padding: 40px 0;
    margin-top: 60px;
}

.footer-content {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
    text-align: center;
    color: #666;
}

.footer-links {
    margin-top: 20px;
}

.footer-links a {
    color: #2563eb;
    margin: 0 15px;
}

/* About/Case Study Specific */
main {
    padding: 20px 0 60px 0;
}

.intro-box {
    background: #f0f4ff;
    border-left: 4px solid #2563eb;
    padding: 24px;
    margin: 30px 0;
}

.metrics {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin: 30px 0;
}

.metric-card {
    background: #ffffff;
    border: 1px solid #e5e5e5;
    border-radius: 6px;
    padding: 20px;
    text-align: center;
}

.metric-value {
    font-size: 2em;
    font-weight: 700;
    color: #2563eb;
    margin-bottom: 5px;
}

.metric-label {
    font-size: 0.9em;
    color: #666;
}

.decision-list {
    background: #f8f9fa;
    border: 1px solid #e5e5e5;
    border-radius: 6px;
    padding: 30px;
    margin: 30px 0;
}

.decision-item {
    margin: 20px 0;
}

.decision-item strong {
    color: #1a1a1a;
    display: block;
    margin-bottom: 8px;
}

/* Responsive */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2em;
    }
    
    h1 {
        font-size: 2em;
    }
    
    nav ul {
        display: none;
    }
    
    .concepts-grid {
        grid-template-columns: 1fr;
    }
    
    .related-links {
        grid-template-columns: 1fr;
    }
    
    .metrics {
        grid-template-columns: 1fr;
    }
}