/* ===== DESIGN SYSTEM ===== */
:root {
    /* Colors */
    --teal-primary: #0d9488;
    --teal-dark: #0f766e;
    --teal-light: #5eead4;
    --gold-accent: #f59e0b;
    --gold-light: #fbbf24;
    --gray-dark: #1f2937;
    --gray-medium: #6b7280;
    --gray-light: #f3f4f6;
    --white: #ffffff;
    
    /* Typography */
    --font-heading: 'Merriweather', serif;
    --font-body: 'Inter', sans-serif;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;
}

/* ===== RESET & BASE ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-body);
    font-size: 1.125rem;
    line-height: 1.7;
    color: var(--gray-dark);
    background-color: var(--white);
}

h1, h2, h3, h4 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.2;
    color: var(--gray-dark);
}

h1 {
    font-size: 2.5rem;
    font-weight: 900;
    margin-bottom: var(--spacing-sm);
}

h2 {
    font-size: 2rem;
    margin-bottom: var(--spacing-md);
}

h3 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
}

h4 {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-xs);
}

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

a {
    color: var(--teal-primary);
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: var(--teal-dark);
}

/* ===== LAYOUT ===== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

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

.section-alt {
    background-color: var(--gray-light);
}

/* ===== NAVIGATION ===== */
.nav {
    background-color: var(--white);
    border-bottom: 1px solid var(--gray-light);
    padding: var(--spacing-sm) 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

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

.nav-brand {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--teal-primary);
}

.nav-brand:hover {
    color: var(--teal-dark);
}

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

.nav-links a {
    color: var(--gray-dark);
    font-weight: 500;
    padding: var(--spacing-xs) 0;
    border-bottom: 2px solid transparent;
    transition: all 0.3s ease;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--teal-primary);
    border-bottom-color: var(--teal-primary);
}

/* ===== HERO SECTION ===== */
.hero {
    padding: var(--spacing-xl) 0;
    background: linear-gradient(135deg, var(--gray-light) 0%, var(--white) 100%);
}

.hero-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: var(--spacing-lg);
    align-items: center;
}

.hero-text {
    max-width: 600px;
}

.hero h1 {
    font-size: 3rem;
    color: var(--teal-dark);
    margin-bottom: var(--spacing-sm);
}

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--gold-accent);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

.hero-description {
    font-size: 1.25rem;
    color: var(--gray-medium);
    margin-bottom: var(--spacing-md);
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
}

.hero-image img {
    width: 100%;
    max-width: 400px;
    border-radius: 16px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
}

/* ===== BUTTONS ===== */
.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    font-family: var(--font-body);
    font-size: 1.125rem;
    font-weight: 600;
    text-decoration: none;
    border-radius: 8px;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
}

.btn-primary {
    background-color: var(--teal-primary);
    color: var(--white);
    box-shadow: 0 4px 6px rgba(13, 148, 136, 0.2);
}

.btn-primary:hover {
    background-color: var(--teal-dark);
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(13, 148, 136, 0.3);
}

.btn-secondary {
    background-color: var(--white);
    color: var(--teal-primary);
    border: 2px solid var(--teal-primary);
}

.btn-secondary:hover {
    background-color: var(--teal-primary);
    color: var(--white);
}

/* ===== VALUE PROPOSITION ===== */
.value-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
}

.value-card {
    background-color: var(--white);
    padding: var(--spacing-md);
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    transition: all 0.3s ease;
}

.value-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 16px rgba(0,0,0,0.1);
}

.value-card h3 {
    color: var(--teal-dark);
    margin-bottom: var(--spacing-sm);
}

/* ===== FEATURED WORK ===== */
.featured-work {
    display: grid;
    gap: var(--spacing-md);
}

.work-card {
    background-color: var(--white);
    padding: var(--spacing-md);
    border-radius: 12px;
    border-left: 4px solid var(--gold-accent);
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}

.work-card h3 {
    color: var(--teal-dark);
}

.work-tech {
    font-size: 1rem;
    color: var(--gray-medium);
    font-style: italic;
    margin: var(--spacing-sm) 0;
}

.section-note {
    text-align: center;
    color: var(--gray-medium);
    font-style: italic;
    margin-top: var(--spacing-md);
}

/* ===== CREDENTIALS ===== */
.credentials {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
}

.credential {
    background-color: var(--white);
    padding: var(--spacing-md);
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}

.credential h4 {
    color: var(--teal-primary);
    font-weight: 700;
}

.credential p {
    color: var(--gray-medium);
    margin-bottom: 0;
}

/* ===== CALL TO ACTION ===== */
.cta {
    text-align: center;
    background: linear-gradient(135deg, var(--teal-light) 0%, var(--teal-primary) 100%);
    color: var(--white);
}

.cta h2 {
    color: var(--white);
}

.cta p {
    font-size: 1.25rem;
    max-width: 600px;
    margin: 0 auto var(--spacing-md);
    color: var(--white);
}

/* ===== FOOTER ===== */
.footer {
    background-color: var(--gray-dark);
    color: var(--white);
    padding: var(--spacing-md) 0;
}

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

.footer-links {
    display: flex;
    gap: var(--spacing-md);
}

.footer a {
    color: var(--white);
}

.footer a:hover {
    color: var(--teal-light);
}

/* ===== CONTENT PAGES ===== */
.page-header {
    padding: var(--spacing-lg) 0 var(--spacing-md);
    text-align: center;
}

.page-header h1 {
    font-size: 3rem;
    color: var(--teal-dark);
}

.content {
    max-width: 800px;
    margin: 0 auto;
    padding: var(--spacing-md) 0 var(--spacing-xl);
}

.content h2 {
    color: var(--teal-dark);
    margin-top: var(--spacing-lg);
}

.content h3 {
    color: var(--teal-primary);
    margin-top: var(--spacing-md);
}

/* About Page Specific */
.about-photo {
    width: 100%;
    max-width: 400px;
    border-radius: 16px;
    margin: var(--spacing-md) auto;
    display: block;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
}

/* Portfolio Page Specific */
.project-card {
    background-color: var(--gray-light);
    padding: var(--spacing-md);
    border-radius: 12px;
    border-left: 4px solid var(--gold-accent);
    margin-bottom: var(--spacing-md);
}

.project-card h3 {
    color: var(--teal-dark);
}

.project-meta {
    font-size: 1rem;
    color: var(--gray-medium);
    margin-bottom: var(--spacing-sm);
}

/* Academic Work Table */
.academic-table {
    width: 100%;
    border-collapse: collapse;
    margin: var(--spacing-md) 0;
    background-color: var(--white);
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}

.academic-table th,
.academic-table td {
    padding: var(--spacing-sm);
    text-align: left;
    border-bottom: 1px solid var(--gray-light);
}

.academic-table th {
    background-color: var(--teal-primary);
    color: var(--white);
    font-weight: 600;
}

.academic-table tr:last-child td {
    border-bottom: none;
}

.academic-table tr:hover {
    background-color: var(--gray-light);
}

/* Insights Page */
.insight-card {
    background-color: var(--white);
    padding: var(--spacing-md);
    border-radius: 12px;
    margin-bottom: var(--spacing-md);
    border-top: 4px solid var(--teal-primary);
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}

.insight-card h3 {
    color: var(--teal-dark);
}

.insight-date {
    font-size: 1rem;
    color: var(--gray-medium);
    margin-bottom: var(--spacing-sm);
}

.insight-excerpt {
    color: var(--gray-dark);
    margin-bottom: var(--spacing-sm);
}

/* Contact Page */
.contact-info {
    background-color: var(--gray-light);
    padding: var(--spacing-md);
    border-radius: 12px;
    margin: var(--spacing-md) 0;
}

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

.contact-method:last-child {
    margin-bottom: 0;
}

.contact-method h3 {
    color: var(--teal-primary);
    font-size: 1.25rem;
}

.contact-method p {
    color: var(--gray-medium);
    margin-bottom: var(--spacing-xs);
}

.contact-method a {
    font-weight: 600;
    font-size: 1.125rem;
}

.open-to-list {
    list-style-position: inside;
    color: var(--gray-dark);
}

.open-to-list li {
    margin-bottom: var(--spacing-xs);
    padding-left: var(--spacing-sm);
}

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 768px) {
    h1 {
        font-size: 2rem;
    }
    
    h2 {
        font-size: 1.75rem;
    }
    
    .hero h1 {
        font-size: 2.25rem;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-image {
        order: -1;
    }
    
    .hero-image img {
        max-width: 300px;
        margin: 0 auto;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 100%;
        max-width: 300px;
    }
    
    .nav-links {
        flex-wrap: wrap;
        gap: var(--spacing-sm);
        font-size: 0.9rem;
    }
    
    .value-grid,
    .credentials {
        grid-template-columns: 1fr;
    }
    
    .footer .container {
        flex-direction: column;
        text-align: center;
        gap: var(--spacing-sm);
    }
    
    .academic-table {
        font-size: 0.9rem;
    }
    
    .academic-table th,
    .academic-table td {
        padding: var(--spacing-xs);
    }
}

@media (max-width: 480px) {
    body {
        font-size: 1rem;
    }
    
    .nav-links {
        gap: var(--spacing-xs);
        font-size: 0.85rem;
    }
    
    .section {
        padding: var(--spacing-md) 0;
    }
}