/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --color-bg: #ffffff;
    --color-text: #1a1a1a;
    --color-text-light: #666666;
    --color-accent: #0066ff;
    --color-border: #e5e5e5;
    --color-hover: #f5f5f5;
    
    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    --font-mono: "SF Mono", Monaco, "Cascadia Code", "Roboto Mono", Consolas, "Courier New", monospace;
    
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 4rem;
    --spacing-2xl: 6rem;
    
    --max-width: 1200px;
    --content-width: 800px;
}

body {
    font-family: var(--font-sans);
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.6;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: var(--spacing-sm);
}

h1 {
    font-size: 3rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

h2 {
    font-size: 2rem;
    font-weight: 600;
    letter-spacing: -0.01em;
}

h3 {
    font-size: 1.5rem;
    font-weight: 600;
}

h4 {
    font-size: 1.25rem;
    font-weight: 600;
}

p {
    margin-bottom: var(--spacing-sm);
    color: var(--color-text-light);
}

a {
    color: var(--color-accent);
    text-decoration: none;
    transition: opacity 0.2s ease;
}

a:hover {
    opacity: 0.7;
}

/* Layout */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.content {
    max-width: var(--content-width);
    margin: 0 auto;
}

/* Navigation */
.nav {
    padding: var(--spacing-md) 0;
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    background: var(--color-bg);
    z-index: 100;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-container.nav-split {
    justify-content: center;
    gap: var(--spacing-lg);
}

.nav-logo {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--color-text);
}

.nav-logo-shapes {
    display: flex;
    align-items: center;
}

.nav-logo-shapes svg {
    display: block;
}

.nav-links {
    display: flex;
    gap: var(--spacing-md);
    list-style: none;
}

.nav-links.nav-left,
.nav-links.nav-right {
    flex: 0 0 auto;
}

.nav-links a {
    color: var(--color-text-light);
    font-size: 0.9375rem;
    font-weight: 500;
    transition: color 0.2s ease;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--color-text);
}

/* Profile Section */
.profile-section {
    padding: var(--spacing-xl) 0;
}

.profile-content {
    max-width: 280px;
}

.avatar {
    width: 48px;
    height: 48px;
    background: var(--color-hover);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-md);
}

.profile-name {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
}

.profile-bio {
    font-size: 0.9375rem;
    color: var(--color-text-light);
    line-height: 1.6;
    margin-bottom: 0;
}

/* Portfolio Grid */
.portfolio-section {
    padding: var(--spacing-md) 0 var(--spacing-xl);
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
    max-width: 600px;
}

.portfolio-card {
    aspect-ratio: 1;
    background: #f0f0f0;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s ease;
}

.portfolio-card:hover {
    background: #e5e5e5;
    opacity: 1;
}

.portfolio-shape {
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Experience Section (Homepage) */
.experience-section {
    padding: var(--spacing-xl) 0;
}

.experience-list {
    max-width: 600px;
}

.experience-row {
    display: grid;
    grid-template-columns: 100px 1fr;
    gap: var(--spacing-md);
    padding: var(--spacing-md) 0;
    border-top: 1px solid var(--color-border);
}

.experience-row:first-child {
    border-top: none;
}

.experience-row .experience-date {
    font-size: 0.875rem;
    color: var(--color-text-light);
    font-weight: 500;
}

.experience-row .experience-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: var(--spacing-xs);
}

.experience-row .experience-description {
    font-size: 0.9375rem;
    color: var(--color-text-light);
    line-height: 1.6;
    margin-bottom: 0;
}

/* Hero Section (legacy) */
.hero {
    padding: var(--spacing-2xl) 0;
}

.hero h1 {
    margin-bottom: var(--spacing-sm);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-text-light);
    max-width: 800px;
    line-height: 1.6;
    margin-bottom: var(--spacing-md);
}

.hero-meta {
    font-size: 0.9375rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-md);
}

.social-links {
    display: flex;
    gap: var(--spacing-sm);
}

.social-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border: 1px solid var(--color-border);
    border-radius: 6px;
    color: var(--color-text);
    font-size: 0.9375rem;
    font-weight: 500;
    transition: background 0.2s ease;
}

.social-link:hover {
    background: var(--color-hover);
    opacity: 1;
}

/* Section */
.section {
    padding: var(--spacing-xl) 0;
}

.section-title {
    margin-bottom: var(--spacing-lg);
}

/* Case Study Card */
.case-studies {
    display: grid;
    gap: var(--spacing-xl);
}

.case-study-card {
    border-top: 1px solid var(--color-border);
    padding-top: var(--spacing-md);
}

.case-study-meta {
    font-size: 0.9375rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-xs);
    font-weight: 500;
}

.case-study-title {
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: var(--spacing-sm);
}

.case-study-description {
    color: var(--color-text-light);
    margin-bottom: var(--spacing-md);
    line-height: 1.7;
}

.case-study-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--color-accent);
    font-weight: 500;
    font-size: 0.9375rem;
}

.case-study-link:after {
    content: "→";
    transition: transform 0.2s ease;
}

.case-study-link:hover:after {
    transform: translateX(4px);
}

/* Case Study Detail Page */
.case-study-header {
    padding: var(--spacing-xl) 0 var(--spacing-lg);
    border-bottom: 1px solid var(--color-border);
}

.case-study-header h1 {
    margin-bottom: var(--spacing-sm);
}

.case-study-header .meta {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    color: var(--color-text-light);
    font-size: 0.9375rem;
}

.case-study-content {
    padding: var(--spacing-xl) 0;
}

.case-study-content h2 {
    margin-top: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

.case-study-content h3 {
    margin-top: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
}

.case-study-content p {
    margin-bottom: var(--spacing-md);
    line-height: 1.7;
}

.case-study-content ul {
    margin-bottom: var(--spacing-md);
    padding-left: var(--spacing-md);
    color: var(--color-text-light);
}

.case-study-content li {
    margin-bottom: var(--spacing-xs);
    line-height: 1.7;
}

/* About Page */
.about-content {
    font-size: 1.125rem;
    line-height: 1.8;
}

.about-content p {
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
}

/* Resume Page */
.resume-section {
    margin-bottom: var(--spacing-xl);
}

.resume-section h2 {
    margin-bottom: var(--spacing-md);
}

.experience-item {
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid var(--color-border);
}

.experience-item:last-child {
    border-bottom: none;
}

.experience-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    margin-bottom: var(--spacing-xs);
    flex-wrap: wrap;
}

.experience-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-text);
}

.experience-date {
    font-size: 0.9375rem;
    color: var(--color-text-light);
    font-weight: 500;
}

.experience-company {
    font-size: 1rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-sm);
}

.experience-description {
    color: var(--color-text-light);
    line-height: 1.7;
}

/* Contact Page */
.contact-content {
    text-align: center;
    padding: var(--spacing-xl) 0;
}

.contact-content h1 {
    margin-bottom: var(--spacing-md);
}

.contact-content p {
    font-size: 1.125rem;
    margin-bottom: var(--spacing-lg);
    color: var(--color-text-light);
}

.contact-email {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-accent);
    margin-bottom: var(--spacing-md);
    display: block;
}

/* Footer */
.footer {
    border-top: 1px solid var(--color-border);
    padding: var(--spacing-lg) 0;
    margin-top: var(--spacing-2xl);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.footer-links {
    display: flex;
    gap: var(--spacing-md);
    list-style: none;
}

.footer-links a {
    color: var(--color-text-light);
    font-size: 0.9375rem;
}

.footer-copyright {
    color: var(--color-text-light);
    font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 768px) {
    :root {
        --spacing-xl: 3rem;
        --spacing-2xl: 4rem;
    }

    h1 {
        font-size: 2rem;
    }

    h2 {
        font-size: 1.5rem;
    }

    .nav-container.nav-split {
        flex-wrap: wrap;
        gap: var(--spacing-sm);
    }

    .nav-links {
        gap: var(--spacing-sm);
    }

    .portfolio-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: var(--spacing-sm);
    }

    .experience-row {
        grid-template-columns: 80px 1fr;
        gap: var(--spacing-sm);
    }

    .hero-subtitle {
        font-size: 1.125rem;
    }

    .case-study-title {
        font-size: 1.5rem;
    }

    .experience-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }

    .nav-container.nav-split {
        flex-direction: column;
        gap: var(--spacing-sm);
    }

    .nav-logo-shapes {
        order: -1;
    }

    .nav-links.nav-left,
    .nav-links.nav-right {
        justify-content: center;
    }

    .nav-links {
        gap: 0.75rem;
    }

    .nav-links a {
        font-size: 0.875rem;
    }

    .portfolio-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .experience-row {
        grid-template-columns: 1fr;
        gap: var(--spacing-xs);
    }

    .social-links {
        flex-direction: column;
        width: 100%;
    }

    .social-link {
        justify-content: center;
    }
}